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Speed,Combat,Scale,Racing => Scale Models => Topic started by: John Witt on June 22, 2009, 07:11:22 PM
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I just ordered a Proctor JN4-D2 from the manufacturer. They are supplying these kits on a made to order basis, and they have a small run of them going right now. It's going to make a pretty substantial Ukie, I think, and should look really great with those big flippers. For those who haven't looked lately, Proctor is alive and well in Canby, OR. The model is 7 foot span and about 11 pounds, may be a two-hander. I've wanted one of these since they came out many years ago, and didn't realize the business had been continued after Lou Proctor died.
http://www.proctor-enterprises.com/
I plan to have one of Clancy's RC throttles and electric power, probably with a belt drive 2:1 reduction.
If there is interest, I could do a build thread on this.
John
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John, please do a build thread. Will make a magnificent model. I don't think line pull will be an issue at the speed it should fly.
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I agree, actually was being a little tongue in cheek. They say three to four weeks delivery from right now, so it will be a little while. Not sure if I can stand waiting, but ahhh, I'm a big boy now. #^ The Paine Field aviation museum which houses Paul Allen's collection has one. They will be flying it as part of their warbird demos on Aug 8th. Hope I can get to that and shoot lots of pictures and video.
Will keep you posted, film at eleven. Pocketa-pocketa-pocketa-pocketa!!
John
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i have about 25 photos - half in color.
tom wilk
tawilk36@cpinternet.com
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I had Joe at the Proctor plant send the plans early, so I could start looking at them and begin planning the construction approach. They arrived this afternoon and boy, what a stack of paper. There are 5 sheets of mostly full size blueline plans that are densly covered with construction notes. This model is not quite a duplicate of full scale construction, but there are not many compromises. I'm fortunate in that there are two Jenny's in my immediate area. One is at the Museum of Flight at Boeing Field and the other is at Paul Allen's museum at Paine Field, just north of me a few miles. Their published schedule says they will be flying their Jenny on August 8th. Hope to be there with loads of cameras. Both of these planes are JN4-D2s, as I understand.
I have used the approach with complex models to treat each subassembly as a model in its own right. This allows one to keep interest high and carry through each portion with a common level of detail. I'll probably start with the tail feathers, just to get used to the materials and construction methods in this kit and try to pick manageable chunks of airframe to deal with. Fortunatly, the Jenny lends itself to this approach because it assembles in big pieces to go fly it. The outer wing panels are removable for transport as rigged pairs.
There are inevitable compromises and one of the areas for this model will be figuring out how to tie the bellcrank into the structure, yet make it unobtrusive. It looks like it can go underneath the front pilot's seat, at first inspection. One thing is certain, electric power is going to make this plane a lot easier to keep clean. It must be a bear to try to keep the oil out of all the nooks a crevices in a ship like this.
Here are some pictures of the plans set. It will be a while before I have anything more to say, as the balance of the kit will be shipped in a few weeks. I thought it was going to be somewhat on the too big side to look nice flying around on wires, but now it looks just right.
Regards to all,
John
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Boy John, what an under taking. This looks like it is going to be a long building session. Good luck on the construction and detailing. Don't forget to keep us posted. DOC Holliday
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John,
When you plan the bellcrank mount, also give consideration to where you will hold the model for a pull test. On some of the R/C to C/L conversions I have done, I have added some support structure, usually to the left side of the fuselage, solely to survive the pull test.
Chuck
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That's a good point , Chuck. Can anyone fill me in on how the pull test is typically done these days. I was thinking about some reinforcing to tie the BC support to the upper and lower longerons. Maybe some carbon fiber painted to look like ash and spruce. The reinforcement, as you say, needs to go to where the load is put in, i.e., the gripping places. This plane only has the sticks, very little in the way of sheeted surfaces, though there are the inside walls of the cockpit area.
I find building this kind of stuff a lot of fun, and as fun, you don't want it to be over too fast.
John
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John, here in the mid-west pull tests are usually done by the owner holding the model however he wants, and the scales are attached to the handle. Then the pilot pulls until the official yells "OK."
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Well some time has passed reading the instructions and looking at the plans, so here are some questions for the group.
1. Covering. This is a 1/6 th scale airplane. What would be a good covering material, since the antique finish Coverite has disappeared. There's silk, of course, but what else is out there.
2. What was the technique used for adhering the fabric to the full scale airplane?. I've only seen one modern airplane covered and the fabric was more or less put on like we do it for models, with pinked tape covering the seams. How was it done in 1916?
3. I plan to use an EPower 46 motor with a 2-1 reduction drive. This will spin a scale 18-4 at about 4500 RM, more or less, which should give about 35 mph flight speed. I'd like to control the speed so I can shoot touch and goes. I was thinking of using Clancy's servo controller, but are there any other suggestions? I'm reluctant to go three wire, plus the Clancy controller offers the potential to have other servos for doing things, like towing and dropping a banner. Does the AMA prohibit using radio control of UC model functions?
4. Any suggestions for maneuvers for added scale points? I hope to work up to a loop, but I think that will be all the acrobatics.
Thanks in advance for the input,
John
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Would be extremely interested in a progress report, with pix, on this one.
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I plan to do so. The kits are being made up in a small production run (I think just 3-4 kits) that is going on now. I expect the kit in 2 or 3 weeks.
John
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John, I'll try to answer a couple of your questions:
Solartex offers an iron on material in a color close to what you want. Check it out at www.balsausa.com. I have used solartex and like it a lot. It is as easy to use as the old Super Coverite. Sig coverall is the same dacron fabric but without the adhesive. You can buy dress lining material at the local fabric shop which is the same stuff. Attach with Stik-it.
One of my R/C buddies is building a Jenny, I'll ask him about fabric attachment. I suspect it was sewn (stitched)on with a specific pattern and knots.
R/C control is not allowed in C/L competition. But you can send the information pulses from an R/C transmitter through insulated lines. Clancy uses this method. I use a JR radio in the direct servo control mode; works great. I concur with your decision not to use three-line mechanical.
You will want 6 optional flight maneuvers--these are the most popular around here: throttle control, high flight, taxi, touch and go (counts as two) and missed approach. I have seen leaflet drops (or in your case could be messages for Pershing chasing the Mexican bandits). I have seen too many C/L scale models wrecked attempting loops, so I would advise against that. I would also suggest you have a backup maneuver in case taxi does not work well with the narrow gear on the Jenny. Lots of models with narrow gear go up on a wingtip on the upwind side of the circle.
Chuck
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Chuck, could you post the details of how your JR setup works? I assume you are also coupling to the control lines. I've been out of RC and UC both for awhile so am not current on all the whistles and bells.
Thanks for taking the time to answer questions.
John
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John, direct servo control is a feature on some radio systems that allows a guy to operate his system without broadcasting a radio frequency signal--for example he needs to adjust something and can't get the frequency control pin. It physically consists of a cable with a "phone jack" that plugs into a socket on the transmitter. At the other end of the cable is a plug that plugs into the charge jack on the receiver battery charge socket on the on/off switch harness. There are two conductors: signal and ground. The signal wire will eventually go to the "battery" connection on the receiver. What it does is take the series of pulses that the transmitter encoder develops and connects them directly to the receiver decoder. NO RF signal. Needing two wires works out well for us C/L guys. I use Deans connectors to splice about 55 of 60 feet of control lines into the middle of the DSC cable. I use one insulated C/L wire and one bare one. I found that two insulated wires cause a lot of friction when flying and I get stickly control around neutral. The JR radio works well for me because I fly lots more R/C than C/L. I use it on my R/C models too. I can set the controls so everything is done with my left hand while my right hand works my trusty, ancient, Darwin handle. My models use throttle, flaps, retracts, and bomb drop via the radio. The fancy computer mixing was very helpful for setting up flaps and end points on throttle and bomb drop. I am also sending a PM.
Chuck
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Turns out there are several threads from folks building Proctor Jennys on RCScalebuilder.com. Great stuff, including people building at a level I will not try to match, however it's very inspirational. I'm really anticipating the arrival of the big box. Worth a look just to drool at the nice airplanes.
John
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See post in the stunt forum about the power requirement. Joe @ Proctor says shipping in about two weeks.
John
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Every time I talk to Joe he says, "two weeks". That's getting kind of old.
I'm off in an hour to the Flying Heritage museum to see their Jenny fly today. I'll post some shots this afternoon.
John
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Here's a few pictures from today. Don't have any good flight shots as I couldn't get close enough. A very smooth running OXX engine in this plane. I'm going to have to go back when they have the plane off the ramp. It was an interesting afternoon with a hangerful of very nice airplanes.
John
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Well some time has passed reading the instructions and looking at the plans, so here are some questions for the group.
1. Covering. This is a 1/6 th scale airplane. What would be a good covering material, since the antique finish Coverite has disappeared. There's silk, of course, but what else is out there.
//SNIP//
John
John, super project. For covering and preparing this machine, please check out the Stits Finishing system:
http://www.stitspolyfiber.com/index.html
Nothing else will do it justice. y1
Best of luck!
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Hope you get your kit soon as I am anxious to see construction photos. DOC Holliday
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Thanks, guys.
I'm getting pretty anxious to see it too. Hoss, I looked at the Stits site, and I assume you mean the 1.5 oz non-certified cloth.
I'm also looking at the Solartex, which looks to be very similar, except prepainted. Some users comment that the weave is apparent, which would be perfect for the Jenny.
Thanks for the tips, I'll keep you posted, starting with a picture of the box #^ #^
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So Joe says the Jenny kit will be ready this Friday. I'm going to the Eugene stunt contest, 8) so the current plan is to go by Canby, which is more or less on the way and pick it up.
If all goes well, I can start with some pictures of the kit early next week. OBoy, Christmas in August! %^@
John
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Thanks, guys.
I'm getting pretty anxious to see it too. Hoss, I looked at the Stits site, and I assume you mean the 1.5 oz non-certified cloth.
I'm also looking at the Solartex, which looks to be very similar, except prepainted. Some users comment that the weave is apparent, which would be perfect for the Jenny.
Thanks for the tips, I'll keep you posted, starting with a picture of the box #^ #^
OK and best wishes with your choice of finishes.
Here are some pictures. The Eindecker is Stits with a couple coats of their clear to maintain the taut. While I did not build this model, I now own it and am setting it up for some additional trim.
In addition the Robin 80 is covered with World Tex, and some 6 coats of Brodak Clear to maintain the tight.
IIRC it was prepainted solartex that I used to cover fuse and lower wing of the Bipe. Still took some clear to maintain tight.
The Mustang fuse and tail were covered with World Tex over finishing epoxy and painted without any weave showing. Wing is monokote over thinned finishing resin. I have a Viking about ready to fly. Wings are covered with another lighter tex material, name blanking out now, but it too has a fair amount of clear dope to maintain tight.
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Nice looking fleet of planes, Hoss. That Eindecker is something else, there's a lot of time invested in those "whirlies" on the cowl.
I went down to to Eugene, OR, this past weekend and flew beginner stunt at the Prop Spinners contest (very well done by John Thompson and crew). On the way, we jumped off the Interstate over to Canby, OR and picked up the Jenny kit. Joe gave me the 10 cent tour and it's a very nice plant. A big investment in machinery and tooling to make these kits is required and the place is well organized to make these complex, high quality kits. There's a big new Fleet bipe in the works for the 30's fans with typical scale structure that Proctor is famous for.
I will get some pictures of the kit this week and post them, serious planning for the construction starts right now.
Regards to all,
John
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OK, So here we go. A couple of pictures of all the goodies in the box. Nice presentation. By picking the kit up at the plant, it didn't get scrambled by the UPS guys, so this is just like it was packed. The scale in the pictures is one foot long. The wheels are not included in the kit--optional extra.
Now to complete the research and planning. I have the Nieto drawings to compare to and plan to get back to the Flying Heritage museum to photograph their Jenny. I have read of some differences in the cockpits and the tail group, so need to resolve those issues.
I plan to order a Turnigy SK 1800 watt motor and 5000 mAh batteries. Assuming 600 watts average power, that translates to about 48 laps of flight at 80% discharge. This is very similar to the motor being used by an RC Jenny at 12 lbs.
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That looks like a builders kit. Also looks like a nightmare to me even tho I love building and not assembling parts. Keep us posted on the build. Have fun, DOC Holliday
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That looks like a builders kit. Also looks like a nightmare to me even tho I love building and not assembling parts. Keep us posted on the build. Have fun, DOC Holliday
I dunno Doc, I have seen some of the Proctor kits, and they are MAGNIFICIENT. However I don't think we will be hearing back form John til maybe 2012??? ??? :o LL~ LL~ LL~
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Well, it might take that long. I have to build an electric Impact in there somewhere also. I glued the first pieces together tonight (8/31/09), the fuselage longerons. These are pre-bent spruce pieces that are spliced in the middle like the original. The sides are built one at a time and not over each other like conventional stick model construction. This is because Proctor have bent the horizontal curve into the longerons where they come together at the tail post. This is a rather abrupt curve which would be difficult without soaking and wetting the wood. The degree of pre-fabrication is pretty amazing for such a complex model.
What you have to decide is how much you want to deviate from a "perfect" scale model to one that can be handled and flown. Most all of the kit compromises I have seen so far, I am willing to make, however since this is an electric model, the nose area can be much closer to scale the a glow engine version.
John
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This evening I was able to get the first fuselage side framed up. This went very well with the larger pieces precut. It is very similar to building a rubber band stick model or, say, a Sig Senorita. All of this is very nice spruce. The side is built over the plans using a set of jig blocks supplied to hold the pre-bent aft fuselage longerons in the correct position. I used cling wrap to avoid sticking to the plans. The building surface is a nice flat piece of 1.5" pink insulation foam.
I've included a picture of a guillotine in my drill press. Just use the chuck to lightly clamp a single edge razor blade and it very cleanly shears off the 1/4 square spruce. I then use a disc sander to touch up the ends for a good fit. My disc sander is in the garage about 20 feet from the work table and it takes about three trips per upright to get the lengths just right. Following the advice in the instructions, I made two of each upright, so all of them are ready for framing up the second side. Maybe tomorrow.
It's amazing how much the French influenced early aviation...all those nice words, longeron, fuselage, guillotine. ;D
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Both fuselage side were framed up this week. I overcame my nervousness about building two separate sides (not on top of each other) by laying the first side down with the top edge, which is straight in the horizontal plane, against the same edge of the second side, so I could align the vertical members up with each other. I guess I should have taken a picture of that, my explanation isn't that good. At any rate, the sides came together fairly well, with a lot of careful sighting and measuring and use of the try square.
The aluminum wire that is used to simulate all the rigging diagonals in the fuselage are installed after the sides were joined. This is done by drilling a slightly oversize hole at the appropriate angle into the intersections of the frame. I used the right angle head on my Dremel to do this. I still will have to do the last bay with a pin vise cause the Dremel is too big to get in there. Where these wires are visible in the cockpit I used a short length of heat shrink on the wire, which was then painted brass color to simulate the turnbuckles.
The Beck plans suggest painting these wires black, but in all the Jenny pictures I have they are a silvery grey color of steel cable, so I am going to leave them the natural aluminum.
I am always amazed that the flimsy sticks build into a strong structure like this. I think this is actually going to be a reasonably robust airframe.
The motor and batteries are supposed to be delivered by the post office today, so I can start working out the mounting and cooling provisions in the nose area. The seat mounts are also going to support the bell crank, so that will get some work this weekend as well.
It is supposed to rain pretty much all weekend, so looks like I'll get some building done on the old girl.
John
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Over the long Labor Day weekend I was able to get some work on the old girl.
The landing gear was next in order to properly locate the lower cross members. The airfoil shaped axle fairing and the two lower blocks come pre-assembled. The gear legs are partially shaped and just need some final shaping and finish sanding to get them ready. I inserted the aluminum end fittings in each gear leg and taped and clamped the assembly together. When everything looked lined up, I CA glued the legs one at a time to the end blocks. Once all that was done, I then wicked some thin CA into the slots in the gear legs that held the aluminum end fittings (fuselage end). After everything set up solid, I drilled and pinned the legs per the instructions using the supplied dowel. The following day I removed the whole gear assembly and added glue everywhere that looked shy. Once that was set up, the ends of the dowels were sanded using a combination of the belt sander and hand sanding. This assembly will get more attention later. I couldn't resist putting the axle in and mounting those wire wheels.
Next up was the tail skid assembly. The pivot part was screwed in place on the rear cross members and a brace wire was formed and soldered in place to keep the skid from swiveling. The skid itself is a pre-cut piece that gets the brass reinforcements nailed on with small brass brads. These pieces are also precut and drilled. I clamped one side in place and drilled straight through with a drill that was slightly smaller than the brads. This keeps the wood from splintering. The brads are too long, so they were all cut down to keep them from butting together in the middle of the skid. The tail skid was stuck in place with a toothpick and a rubber band to see how it looked.
Had some fun fitting up the radiator shell and tried a car-modeler trick--Bare Metal foil. The wooden shell was sanded and several coats of Luster Kote primer applied until there was a smooth finish. The gold foil was then applied in pieces working from back edge to the front. Proctor supplies a piece of copper screen to use to simulate the radiator core. I cut this to shape and made a frame of 1/16 dia K&S copper tube which was soldered around the edge of the screen. Proctor also supplied the brass oval part that goes around the prop shaft. The shell was match drilled and tapped to the front fuslage former so it can be easily removed. A coat of clear lacquer keeps everything from tarnishing (I hope).
The bellcrank installation is next, and I am in the middle of planning that. The bellcrank mounting will interfere with the scale furnishings in the forward cockpit, so I am trying to keep that to a minimum. Since the plane will have to pull test 50#, feeding the bellcrank loads into the structure is critical to keep the whole thing from exiting out through the port side.
John
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Not a lot to report from this week, busy at work and home with other things. I did start on the control system, laying out the design and building the cross bar that pull-pulls the elevator control wires. This cross bar assembly mounts behind the aft seat and was connected to the stick in the real airplane. In this case it will be actuated by the bellcrank pushrod and the connection to the scale stick will just float on the tube. I can't make this a working connection because the front stick interferes with the bell crank.
The pieces are made from K&S brass tube and 1/32 inch thick brass sheet. The sheet parts are cut out with aviation snips and ground to shape with my belt sander. The pictures show the pillow block end bearings being made up and the elevator horns and cross tube.
I have a pair of small machinist's vises that I use for things that are easy to hold. Even very simple fixturing makes it possible to get the parts soldered together with good quality joints and the correct alignment.
Once the bell crank installation is worked out and installed, I can put in the cockpit floor, seats and then begin on the top cowlings. At that point it will start to look more like a Jenny you could take to the dance.
John
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I can see this is a work of art. I do not have that kind of patience. DOC Holliday
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Thanks, John. Just one bit at a time. You have to find satisfaction in smaller increments, I guess. I find it does take a certain amount of perserverance to keep a long project from getting totally derailed by other things. I have a 1/350 scale BB63 ship model that's going on 5 years now, but it's nearly complete, somewhat derailed by the Jenny, which is somewhat derailed by flying stunt, which is...you get the idea.
John
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This working for a living is getting in the way of the important stuff. I've resolved to get at least one thing, no matter how small, done every day.
This week, I was able to get the bell crank, pushrod and mounting done and test fit into the framework. The big fun came, however as the last pieces of the control system arrived and I was able to set it all up on the bench and run the motor with full throttle control.
The first picture shows the bellcrank in place. The crank is made of two pieces of .050 circuit board material. It has a center spacer made of nylon and a pivot post I turned from a piece of aluminum rod. A 6-32 screw mounts it to the 1/4 ply mount which is glued to the 1/4 square spruce seat rails. The inside seat rail is reinforced with 3/16 square carbon fiber tube. There will be some reinforcements added to the vertical posts later in the construction after the lower wing fittings are in place. The leadouts will be flex cable, so there are turned nylon ferrules that look like small pulleys at the ends of the bell crank. The carbon pushrod is from a Brodak set. It connects to the crossbar which will later have the scale elevator control cables attached.
The second and third shots show the control layout with the motor at a 700 rpm idle. This is the Clancy Arnold system which encodes a 4-channel pulse width modulated (PWM) signal to the control lines, which is then decoded in the airplane. The decoder then outputs a 1-2 millisecond square wave signal which can be decoded by standard RC servos and the ESC.
In the pictures the motor is idling at 700 rpm. I substituted an audio taper pot (Radio Shack P/N 271-1721) for the linear slide pot included with the system to get a finer control of the low end of the rpm band. The yellow/white wires represent the control lines. The red black wires connect a 9V battery which powers the encoder. The decoder gets its power from the Castle ICE speed control. The green/yellow pair connects the pot to the encoder. The encoder and decoder are encapsulated with a red potting compound, which protects against environmental damage and vibration. Note that there are 4 channels, so I could have three more functions besides throttle.
The last shot is a picture of the 100Amp ICE ESC.
We're having fun now!! #^
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Getting to the shop and doing a little at a time makes for great strides in building. Even being retired it takes me a while to finish planes. That shot of the bellcrank system is awesome. DOC Holliday
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A short pause in the Jenny building to assemble a new Randy Smith Vector 40.
John
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John
Glad to see that you covered the pins on the extra three channel output cables. No shorts needed or wanted. Looks like a good working setup of my U/Tronics Control system.
Keep up the good work,
Clancy
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John
Your Proctor Enterprises Jenny is looking great. I think i'll order a VK Nieuport 17
builders kit after im finished with my Fokker D7.
I wanted to ask you about how does a tailskid aircraft handle take off's and landings
at an event such as the NATS? Or other hard surface flying areas.?
Bryan
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Bryan,
I've never competed in U/C scale with a tail skid airplane, so I'm not sure what will happen. I do not plan to taxi the airplane, so that should minimize the grinding of the skid on the pavement. I plan on replacing the skid wear strip from time to time, as well. The wear strip on the Proctor kit is brass, which will wear through pretty quickly on paving, I may switch that for a steel strip before I fly the first time. I normally fly from a grass field , so the brass shouldn't be an issue there.
The skid won't give much directional control to the plane, I suspect, but I plan to get the tail up anyway. As far as I know, in real aircraft, the tailskid shoe just got changed as needed. Of course, most fields were grass anyway
The VK Nieuport should be a great airplane. I always wanted to do one of the rotary engine birds. With electric power, you could move motor back and make a long propeller shaft that would go through the dummy engine. If the dummy engine rode on a pair of bearings on the propshaft, the bearing drag should make it rotate, just not at the high RPM of the prop.
Anyway good luck, and post some pictures of your D-VII.
John
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Thanks John
That is a cool idea you have there with an electric set up with a bearing on the dummy
engine.
I have been looking at RCSB alot to learn about scale proctor kits and there are many
tail dragers of course ww1 . I think that the tail movement in cl scale flying should be
minimal. I will know for sure when i get mine flying but i dont think there would be
any tail looping, there is just to much friction for that to happen.
Good job on your Jenny Bryan
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Don't forget that WW I aircraft tend to be tail heavy. So moving the motor back could cause a balance problem. Look for ways to move the battery way forward. My 80" Eindecker had a 1lb of lead in the noise. I like the turning dummey rotary engine but I would make it hollow shafted and run the motor shaft through without touching. I would let the dummey engine windmill. Now you have a long motor shaft unsupporte at the prop end. This is a very intersting design project. Not simple for sure.
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I'm not sure what would cause the dummy rotary to turn if it was left to windmill, unless maybe some small vanes could be attached to the cylinders so the airstream could move it. I was sort of thinking about a tube through the crankcase with a ball bearing at each end, with the inner races on the prop shaft. Maybe one of those nice Williams brothers rotary models could be the dummy engine. Just day dreaming, y'know. #^
Any airplane needs to be balanced correctly, especially WWI types with those little tails. You'd certainly need to address that in the design work.
The Jenny has a 1.25 lb battery for the initial nose weight, but we'll see how much more it takes after more of it is built. Jennies are know for being good fliers in the RC world, so should be possible for U/C as well. That's true for the Nieuports too, but correct balance is critically important.
John
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Hi John
Yeah i see what you mean. Been looking at all the rc planes at RCSB and that is always
talked about. Proctor Enterprises under kit manufactures at rcsb has great ww1 builds
and tail weight is a major concern.
I have always liked ww1 war planes ever sense i was a kid. Know seeing so many
modeled i cant wait to start on my own control line version. I ordered 1/6 scale
Fokker D7 plans from Arizona Models. The engine will be a RCV91-CD 4stroke.
I am real excited the build will probably take 13 months. I have been researching
how to apply scale details and you sure are doing a great job on your Jenny. D>K
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Okay, back to working on the Jenny. I've been building an e-powered Vector 40, which is now in the color trim phase, so lots of time to do other stuff while the paint dries.
This afternoon I built the lower wing mounting hardware, which consists of 4 .030 thick aluminum strips which are mounted in slots in the fuselage uprights. The lower wings eventually will be pinned to these brackets.
I also did some careful measuring and comparison with the plans and it appears that the Proctor-supplied front cabane struts are too short by about 1/8 inch. This means the upper wing would have the wrong incidence. It looks as though it's possible to re-drill the struts and still use them, but I think I will make some new ones rather than risk having the mounting screws pull out. So it's two steps forward and one back, but better now than later.
The next steps will involve putting in the cockpit flooring and dummy controls, all the stuff in the bottom that will be hard to get to later.
More pictures soon.
John
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Back to rotating dummey engine. How about an out-runner brushless motor and mount the dummey engine to the case? Biggest problem would be rotating mass and balance. Lets face it. The original WW I rotary engines were a dog because of excessive rotating mass. LL~
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So the winter weather has set in Seattle and it's back to some serious building. Here are some update photos showing the lower wing attachments and some new cockpit detail. The cockpit details are not included in the kit, so all of that is scratch built, primarily of brass and aluminum tubing, styrene and plywood. I'm trying to get all the stuff down in the bottom built so that the upper stuff (seats up to cowlings) can be added without having to reach over it. So far what's in there are the rudder bars and their pivots and the for-aft cables that link the bars.
I also made the outer covering of the engine cowl so I could start figuring out how to mount the servo encoder, battery, ESC and the safety plug. The plug will be behind an openable panel in the side engine cowl.
I was hoping to be able to add more extensive engine detail than the kit supplies, but alas, it appears the battery is in the way no matter what I do.
The turtledeck is glued to the fuselage sides if built with the kit parts, but it is relatively easy to trim the formers and add additional stripwood to simulate the removable assembly as on the original Jenny.
John
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So here's the current state of things. The control pieces that go in the cockpit bottom were built up and installed on top of the floor boards. These things are made of sheet styrene and brass. The control sticks are dowels that I sanded to shape while spinning in my drill press.
Next was the installation of the motor and the lite-ply structure that holds the battery. The ICE 100A ESC is mounted to the side with servo tape and there is a spot on the outside wall for the decoder and its wiring. Also on the outside will be the controls enable switch and the safety plug. I could include a charge plug, but I fret over the possible hazard of losing the plane to a battery fire, so may leave that out and remove the battery for charging. Also the bottom skin of 1/32 ply was added to the fuse. This skin will be finished out to represent the aluminum sheet on the real plane.
The next chore, and it really was a chore, was building the three aluminum and plywood cowlings. These are cut from a supplied sheet of fairly hard temper .010 thick aluminum sheet and three pre-cut 1/32 ply skins. The plywood skins are soaked in hot water then wrapped around a 4 inch diameter plastic bottle, taped down with masking tape and then microwaved to steam them to shape. I wrapped the tape around sticky side out to avoid permanently gluing it to the skins. Before the skins were steamed, I used them as patterns to cut the cowls out of the aluminum sheet, allowing a bit extra for final trim.
After some test fitting, the ply skins were positioned on the airplane and then the aluminum laminated to the ply with slow CA. I covered the fuselage structure with saran wrap to avoid gluing the skin to the structure. In the picture, the cowls are trimmed to shape, but still need to have the mounting holes, windscreen holes, strut holes, etc., cut in. The front cowl has internal bulkheads to position it securely on the nose and allow mounting the dummy engine parts.
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Another update. I'm trying hard to keep to my goal of doing at least one little thing each and as a result, there is some discernable progress. I have been making up some sub assemblies: the three cowlings which are nearly done and several bits for the controls. Last weekend I made up the four cables that connect the elevator horns with the elevators and with that was able to permanently install the horn assembly and its pushrod. Tonight the leadouts were assembled and the bell crank installed, hopefully for the last time. The biggest news is that I covered the port side of the furselage! The leadout holes were cut in the Solartex and now I can pull on the leadouts and watch the horns move and fantasize about takeoffs and landings.
I'll have some more pictures in a few days.
Regards to all,
John W
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John
Have you decided on an inconspicuous place to mount the connector to connect the leads from your flying lines? I use 3/32 miniature earphone jacks and plugs. Center tip - Signal and outer sleeve - Return/ground. By using them I can never hook up the U/Tronics with the signal and ground reversed. I also color code the wires from the phone plug to the flying lines so that it is a no brain-er to connect the lines correctly, BLACK is DOWN. I still check the elevator each time before takeoff, except on a P-38, You can not see the elevator on a P-38 from the center of the circle.
Clancy
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Thanks for the suggestion, Clancy. I plan to have all the external connections behind a opening panel on the outside of the nose. There is a scale engine access door there. The line connections I hadn't thought about yet, so I appreciate the heads up. I'de like for that connection to be pretty small and was thinking about a two pin Harwin which is one we use at work and which is polarized.
The connections are: safety battery plug, and a two pole single throw miniature toggle to enable the ESC and decoder at the same time. Then of course, on the other side, the two wires from the lines.
Thanks for the suggestion, I'm sure looking forward to seeing the engine run up from the handle end of the lines.
John W
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For what it's worth I found that two insulated line are better than just one. The problem I had was uneven line drag. I started out with 70' lines on my 90 ST powered Extra 300S. I had the one insulated line as the up line. When throttling back and on the upwind side of the circle the lines pull went down. With the increased drag on the up line the Extra 300S would go into a clime. I almost lost it before I figured out what was going wrong. I also found that it is best to use a fiber glass bell crank and a insulated controll handle setup. This setup makes it virtually impossible to short the two lines out. By the way I use standard Futaba servo connectors to tie it all together. I use black for return and white for signal. If you plug it up backwords it doesn't hurt anything. It just doesn't work. 3' aileron extender cut in half makes a mating pair.
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I've had a comment that two insulated lines are sticky sliding together. Have you noticed that effect with your Extra? The lines I have are Brodak's.
I do have an fiberglass bellcrank and plan on building up a special handle for the Clancy encoder setup. I'll probably stick with the RC type connectors everywhere except I do like Clancy's miniature phono plug connection for the aircraft side.
I had thought about the uneven drag issue, but had no way to know how big a problem it would be. You are undoubtedly flying faster than I will, but I wouldn't like to have an unwanted control input either. Did you end up staying with the 70' lines?
Thanks for the comment. Perhap's I'll run a backyard experiment to see how it feels.
The Jenny has rather large, unbalanced elevators. I'm somewhat worried that will result in unwanted nose down trim. Anybody have any experience that applies?
John W
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I am using deep sea fishing leader. I did not notice any problem with line rub. However understand that I start out with no twist in the lines and I do not loop. For the most part my lines do not touch. At full power with smoke ON it pulls like a bear. It may be interesting to see how it feels with twist in the line. I am looking at a FUN-SCALE Extra 300S and hopefully it will loop. With it I plan to start with 2 turns in the line. At the end of the flight with 3 loops I will have 1 turn in the line.
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Here's an update on some recent progress.
The fuselage is coming along nicely. I covered the port side and then installed the bellcrank and leadouts, rough cutting the holes for the leadouts. These holes will get styrene doublers and an extra layer of Solartex covering to reinforce them, similar to the way real aircraft are done, then trimmed out to look nice. Also the four wires which actuate the elevators have been installed and the whole control system finally permanently mounted in the fuselage. The wires are tied off until the stab can be mounted.
Next was to cover the turtledeck and the starboard fuselage side. This a pretty easy covering job, but suddenly it is starting to look a lot more finished. I think that is the way all this works, you develop lots of little assemblies, then all of a sudden you get a reward as the project takes shape.
Today's task is to hook up all the switches and wiring and provide the plug-in for the flying lines electrical leads, the safety plug and the encoder on-off switch. I have to make a quick trip to Radio Shack for a panel mount phone jack for the flying line leads, but otherwise everything is handy.
Following the wiring, I have to trim out the three cowlings and paint them. At that point the cockpit cowls can be permanently installed and a number of other prepared pieces will be added.
I also started building the stab and elevators. The kit includes some bent reed pieces for the outlines, but following a suggestion from John Cole on RCScalebuilder, I made these out of aluminum tubing. To do this a piece of 1/8 OD tube was slipped inside a piece of 5/32 OD tubing to double the wall thickness. I then cut a 1/4 plywood outline to bend the tube around. There is some springback, but the jig sets the basic shape and location of the bends which are then gently hand worked into a match to the plans. Since the picture was taken, the stab has been about 80% completed.
Regards to all,
John W
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A man of patience. That is so awesome what you are doing.
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That stabis really slick. Model is progressing very nicely.
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Thanks for allowing us into your workshop to watch you work. Really enjoying the build. H^^
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Thanks for the kind words. I'm glad someone is looking at this stuff.
I don't consider myself a super builder, but I have been at it for awhile, starting with 10 cent Comet kits when I was about 5-6 years old in the early 50s. I was in Savannah, GA, and my dad was stationed at Hunter AFB, working on B-29s. Milk came to the front door via a horse-drawn (no kidding) wagon. The dairy switched to Divcos while we were there.
I try to strike a balance in the detail department that will let me live long enough to finish and fly the plane.
Anyway, I digress. Got the stabilizer and elevators closer to completion as well as mounting the switch panel in the forward cockpit. Here's a shot of the stabilizer/elevator structure, ready to cover. Note that beside the ribs and spars, there are a bunch of little blocks used to mount the flying wire fittings. Everything has about twice as many parts as you think. They aren't hard to make, just a lot of them. Second shot is of laying down the little glue stripes that simulate the rib stitching. These are covered with rib tapes cut from Solartex and ironed on. Last picture is of the assembled stab and elevators with the horns installed. Next stop is the elevator wire rigging, then the assembly can be glued to the fuselage and the controls hooked up.
John W
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This is so facsinating. Thanks again for letting us wander into your shop! H^^
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More on the stabilizer. I thought this would be pretty fast, but as in all scale stuff it's easy to get carried away.
The elevator control wires and bracing wires are now installed. I was just finishing the last one of the 12 wires which brace the elevators and when trimming the tag end of the wire I snipped the brace wire also, so ended up with thirteen of these. HB~>
The elevator horns that come in the kit are pre-cut aluminum sheet parts. The real ones are made of steel stampings welded into an oval section. I made a flange for the mount end and then laminated balsa to both sides of the sheet metal horns. These were sanded to shape and painted to look (more or less) like the originals.
Part of the art of building scale models is picking your compromises between the model and the prototype. The only way to be accurate is to fabricate miniature parts exactly like the real plane and if you do that, you might as well build the real one (cost no object!!).
I've always felt that the idea is to create a satisfactory illusion of the prototype, so any technique to that end works for me. A few more detail pieces and the stab assembly will be done for now. Thanks for checking in.
John W
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Beautiful work John, and a great subject. Maybe it will encourage me to finish my Bucker Jungmiester that I scratch built some years ago. Mine is covered with Sig Koverall, and finished with Sig butyrate over Sig nitrate. I originally built it for R/C, but am thinking of making it C/L, or maybe both. Mine only has a 66" span, but will weigh in at about the same as yours. I know guys are flying C/L scale planes this big, but I have not seen one. I will be looking forward to your flight report. " With pictures"
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Jim,
By all means, finish it up, we need more scale builders/fliers. Start a thread and tell us about, especially if you work out how to make it RC and UC. There is a lot of info out there on Buckers, try RCScalebuilder.com for some RC build threads.
John W
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Over the last week I was able to get the vertical fin and rudder built. The construction is very similar to the stab and elevators, using aluminum tube for the outlines. Here's a picture of them sitting in place, but not attached. I'm trying to figure out how to anchor the rudder control wires inside the fuselage and still be able to do some fine adjustment for flight trim. I will somehow have to get to the adjustment which would be low in the rear cockpit. I can put in a couple of turnbuckles, or possibly have them actually attach to the rudder bar and somehow anchor it. I like that idea from the scale standpoint, but haven't yet figured out how to do it.
The second picture is of the beginning of the fabrication of the beading that borders all the cockpit cowlings. On the full scale plane, this beading is rolled into the sheet metal to stiffen the edges. The beading machine has positive and negative rollers that shape the metal. The model's cowling metal is too stiff to do that at this small scale, so I am simulating the effect by shaping and gluing half round styrene strips. The strips are .080 inch wide which is a good match for the beading that is formed into the side cowls which came in the kit.
That's all the recent progress, I hope to get some work done in between holiday events.
Best wishes to all for the new year.
John W
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I have had a bad cold for several days and haven't gotten a lot done. however here's a little progress:
The rudder and fin are now installed and rigged as is the turtledeck. Actually the empennage rigging isn't finished as there are two struts up to the bottom of the stab and a brace wire on each side of the fin, but it's getting close.
The second photo is of the forward cockpit cowl and cabane struts, showing the beading on the cowls. This is made of Evergreen .080 wide half-round styrene bent to shape and glued on with ACC. This worked out better than I had hoped, as I had anticipated it would be hard to bend without cracking. Turns out that if the bends are done gradually with a little "stretch" time between tries, it will go around very nicely. I think the styrene creeps into its new position if given a little time. I want to have this cowl removable, so this is a test fit to verify that.
Also, you can see the copper wrapping on the strut ends. This was done with .003 thick copper sheet that is sold for embossing. In a real Jenny, every strut end and many of the structural member ends are treated with nailed-on copper sheet as a reinforcement.
Hope to get the aft cowl done in the next day or so if I can shake this cold.
John W
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Beautiful work John. I am so impressed with how quickly your build is progressing. What Solartex did you use; isn't there a linen and a natural? Have you doped it yet, with what, and what color scheme have you decided on?
Thanks, Jim
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Thanks guys,
Real Jennies had a couple of coats of dope to tighten the fabric, which as Ty mentioned is sewn as a bag then pulled over the wing and stitched closed. The dope was then overcoated with varnish, of all things. The varnish of course would weather very quickly and turn yellowish brown. The fabric was initially a natural linen color, which is what I've chosen to have on my Jenny, using Solartex Natural covering. It looks pretty good and I like working with the Solartex. It is a bit expensive, I bought a 10 meter roll which was about $100. It is however a good match in weave for the 1/6 scale of the Jenny and doesn't require any further finish. I helped cover a plane when I was a kid and the finish looks like what I remember after a couple of coats of clear.
There are some really great Jenny pictures on Brian Karli's Jenny restoration blog, which I have extensively used as a reference. This guy is a meticulous craftsman.
http://curtissjennyrestoration.blogspot.com/
I'm feeling a bit better today, so hope the cold is going away. I want to fly the Jenny in April and compete in the NW Regionals in May, so I have good carrot to keep me going. I am gratified by the amount of interest in this build and I hope it will inspire others to get into scale modeling. There are a lot of aspects to it, the research which opens a window into the incredible history of aviation, is one I particularly like.
The building of a plane like this is mostly a matter of dealing with one thing at a time, and isn't really much harder, if any, to do than building any other flying model. There is just more of it to do before you get the gratification of flight. If you mess up a part, you just make another one. Come on you guys, get after it, pick out that favorite plane.
Regards,
John W
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That is some craftsmanship. We did get to see a Jenny landing at Wichita KS one year as we were going south on I-35. I thought it was going to fall out of the air it was going so slow. People thought we were having car trouble as we stopped to watch it land. HAVE A HAPPY NEW YEAR
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Jenny's cruising speed is about 65 mph, and I think they land at about 50. The OX-5 only makes 90 HP but apparently makes a lot of torque, swinging an 7 ft propellor at about 1400 RPM. Given the low wing loading, they go pretty slow. Here's a link to a flying report on the Hisso powered Jenny at Old Rhinebeck. Keep in mind the Hisso makes 140 HP, so you can imagine the climb rate with 90 HP. As I recall it was about 250 ft/min.
Another interesting thing about many early airplanes is that they didn't have a very wide performance envelope. The take-off, cruise and top speeds were just a few MPH apart. Among other things it makes them sensitive to wind and weather as there is no performance margin.
http://www.airbum.com/pireps/PirepJenny.html
John W
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Among other things it makes them sensitive to wind and weather as there is no performance margin.
http://www.airbum.com/pireps/PirepJenny.html
John W
What a great read. Thanks for posting the link.
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Looking great John; There were some good shots of Jenny's in the Great Waldo Pepper movie also. A very nice Bucker in there too, only it had the engine changed from the radial to a flat with cheek cowls.
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That is a great story of a lady called Jenny. I keep telling myself I was born way to late to enjoy the days of the Jenny.
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Waldo's plane was actually a Standard J-1, which looks a lot like a Jenny and has similar performance. Lindberg's Jenny still exists. It is in a museum now, one of those "found in a barn" stories.
http://www.williammaloney.com/Aviation/CradleOfAviationMuseum/LindberghsCurtissJenny/pages/01LindberghsCurtissJenny.htm
John W
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New bits added on. Finally got to the point of painting the three cowlings Olive Drab. I still have to drill all the holes for the little retaining screws and I haven't quite been able to get the courage for that just yet. I also have to make the windshields and apply them to the top cowlings before I can permanently install them. I spent part of the morning cutting out the louver holes in the side panels. These are thin vacuum formed ABS parts. I used a small router bit in the Dremel tool to slot the material, then a combination of careful carving with a #11 blade and filing and sanding to clean out the openings. Once the louvers are cut out, then a set of braces made of styrene is applied to the inside surface.
I got some work done on the landing gear too, adding the thread wrapping to the front legs. I ran out of thread which is, naturally, a weird type called "carpet thread". So far I haven't found any more like what I have. I hope I don't end up having to strip it off and go with something else. I made the copper cladding for the fuselage end of the struts and shaped and screwed in place the aluminum axle guide plates. These are cutout aluminum pieces that come with the kit. They are not quite the right shape, but close enough to create the right visual impression. I did some filing and drilling that makes them a little closer to the prototype. The bungee cords were added and the axle and its various bushings and retainers put on as well. I couldn't resist putting it all together for a look. #^
I discovered some black .010 styrene sheet at Galaxy Hobbies which will work nicely for making the clips which hold on the landing gear, as well as some of the other parts for the fuselage. Having black will save painting a lot of these little parts. One of the real virtues of electric power is not having the added headache of trying to fuel proof all this stuff, wow, my hat is off to those who do that.
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Hi John. Get yourself to a carpet store that also does installs. You should be able to get the thread there. Beautiful job on the Jenny. Am really enjoying the build.
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Here's a quick note showing the bottom sheet metal cowl. Four half round styrene strips are cemented to a sheet of .010 styrene that will later be glued to the plywood fuselage bottom. The strips will simulate the rolled-in beading that stiffened the full scale sheet metal panels. A styrene tab will be added to form the part of the cowl that covers the bottom of the radiator.
There is a second piece of sheet metal that covers the bottom of the fuse back to the middle of the wing. It will be made in a similar fashion. Both of these will be painted and glued on and the fasteners added later.
I'm having some trouble coming up with a good way to model all these small screws. The real cowlings have about 60 screws that appear to be #10 (3/16 inch diameter) holding them on. I have some model railroad nut-bolt styrene castings that are about the right size, so I'm going to make up a sample piece and see if they look OK. The brass pins that came in the kit scale out to be about 5/8 inch in diameter which is way too big.
Also, another small milestone, the side cowlings are mounted and the final bits of rigging on the empennage were finished. The stabilizer/elevators turned out to have 138 distinct parts. Sounds like a lot, but it's just one or two at a time. The whole thing is beginning to have that intricate patina that is so distinctive about these early airplanes.
I'm also starting to round up the materials for the wings.
Regards to all,
John W
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Man see looks GOOD! Hope it flyes well. If it does she will be a contest winner!!!
y1 y1 #^ H^^ H^^ H^^ H^^
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That is just so cool. Thanks for inviting us into your shop. Have you considered vacforming the nuts and bolts? Make one template with maybe ten on it, then vacform as many as you need. Just a thought. Peace to you and yours. H^^
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Thanks for the suggestion. I've never done any vacuum forming, so I hadn't thought of that. What I'm after is pretty small, only about .063 head diameter (1/6 of 3/8). I found some model railroad cast styrene rivets that look promising, made by Grandt Line. Will post how it works out. I'm making the exhaust manifolds today. They are carved wood, plus bits of wire. I'll post some pix of the whole OX-5 engine setup in a few days.
John W
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John, don't know quite what the screws look like, but silicone rubber molds are easy to do and work pretty well for small parts. If you have never made/used them google smooth-on for their website and tutorials on how to make. It is very easy.
Chuck
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Thanks, Chuck. I really need to learn how to do that. The need for cast urethane pieces comes up now and again. I have a 3/8 inch scale Crowley Invader class tugboat project waiting in the wings that will need a lot of cast ports, doors, vents, etc. Another big project.
Jenny will get added pieces for some time after she flies. I'd like to finish out the cockpit with a good amount of detail, even though it's not required for sport scale. Some of the instrument housings would be good as castings, especially the compass.
A later addition to this post. Got a fair number of small pieces, the windshields and exhaust manifolds finished and installed today. The first decent day of work on the plane in three weeks--must be getting over my pneumonia! #^
Regards,
John W
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I have started making wing ribs and trying to get my head around the ins and outs of the wing construction. I also scanned and enlarged the "ASMS Kelly Field 2805" markings that go on the side of the fuselage. These are scanned from the Joe Nieto drawings and enlarged to fit 1/6 scale.
My plan is to trace these on frisket paper to make a mask, then airbrush them on.
If anyone would like a copy of the JPGs, e-mail me and I'll send them. The two files are about 10 mB each and broken down to print on 8.5 x 11 paper.
John W
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John, your detail is looking fabulous!!!! Especially the engine and louvers.
Will
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WOW!! Great looking plane! Thanks for all of the pics through the build.
David
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Thank you for the kind words. It sure helps keep my enthusiasm high to know that someone else is interested in this stuff.
Today (Sunday, Jan 17) I got the first wing panel off the table. Not finished, of course, but the initial frame is all there. I was capstripping ribs off and on for the last week.
It turns out that the wing tip construction per the kit and Beck plans is not quite right. The plans call for one of the full depth ribs as the last before the tip bow, and the real Jenny has a slender section rib there that makes a more nicely tapered tip. I took one of the ribs and laid out a 1/32 ply solid rib with the correct section, which has the cap strips just touching the spars. This leaves no material above and below the spars to hold the LE and TE of the rib together, so I left little bridges above and below the spar cutouts. These were trimmed off after the rib was in place and then the cap strips were added.
The kit also supplied bent reed pieces for the tip bows and the S-curved TE piece that goes at the inner end of the wing. I replaced these with 5/32 doubled wall aluminum tube as I did with the tail feathers. This also allowed getting the correct arch to the bow to match the revised tip section.
The wing still has to have all the LE/TE and tip shaping done, the intermediate false ribs and the 1/64 LE ply sheeting. There are also the blocks that allow mounting the fittings for the interplane struts and brace wires. This stuff is all made from very nice quality spruce supplied partly precut.
I spent a little quality time admiring the wing attached to fuselage and wondering how I will manage to pick this airplane up when it is finished. There are wires everywhere!
Thanks again all for your comments and advice.
John W
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Saturday morning report.
I was able to get some more tubing from the LHS yesterday, so I got the other lower wing framed up this morning. Careful not to build two for same side. I had gotten all the ribs done last week while waiting for the tube, so this went pretty fast -- practice, practice.
Also acquired a small servo to use for a tow hook at the tail. If the plane flies well enough, I'd like to tow a banner and be able to remote drop it for landing.
John W
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Ty, the right and left wing pairs come off as a unit, so the size is reduced somewhat. It's 87 inch span, 1400 square inches area. Gonna be a handful to carry around.
This last week I was able to get the first of the upper wing halves framed up and that is now ready to shape the LE and TE. The next step is to frame out the aileron structure within the wing frame and the two can then be sawed apart. At least that's the plan, there is always something unforeseen that crops up when actually fitting the pieces together.
I borrowed a drafting compass from a colleague at work ( he's much better than a mere coworker) and cut the masking frisket for the markings on the fuselage. Here's a sequence of pictures showing that process. The frisket film is a .002 inch vinyl film with a low tack adhesive and a backing layer. The backing is translucent so you can cut a mask out of the film by taping it down over a pattern, then cutting just through the vinyl film. I cut away part of the backing and stick the film down lightly and when it's in the right place, gently peel off the rest of the backing. Works pretty well for one-off custom markings. The lettering and cockade were both done this way, from a pattern enlarged from Joe Nieto drawings.
Lastly, I had a visit from a nearby RC flier, Brian Taylor, who is also building a Jenny and has done some really nice cockpit detail in his plane. It is interesting to see two planes built from the same kit and to see how an individual's priorities influence how it comes out. A very enjoyable afternoon, swapping lies and comparing techniques. Glad I don't have to mount all those servos.
Regards to all,
John W
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Last weekend and in evenings this week, I was able to finish the left wing and now have about 85% completion on the right one. Here's a shot of the left wing with the aileron cut away. The ailerons are fabricated using the existing ribs in the wings structure. The space on is top of the spar filled in between the ribs with 3/16 balsa. After that is done top and bottom, next is to measure and cut out a portion of the ribs equal to the aileron spar thickness (1/4 inch), plus the hinge gap (3/32). The aileron spar is then inserted and spaced 3/32 inch from the rear wing spar, which, if everything is cut correctly leaves the aft part of the ribs touching the spar. The ribs are then glued to the spar. Once everything is set up then the aileron spar is sanded flush with the balance of the wing. This procedure is only fleetingly covered in the instructions, so some of this is my own invention. n~
After all this the leading edge is sheeted with a strip of 1/64 ply, and the intermediate false ribs cut from some balsa stock supplied, and they are glued in from the bottom. This aileron business has so far been the touchiest construction in the whole project. I expect the right wing will be finished by this weekend.
While the glue dries I have been varnishing the interplane struts (the long ones between the wing panels) and have started coppering the ends and applying the end fittings, which are bolted on with two 0-80 brass screws each. These are not exactly correct scale, but look pretty good.
Regards to all,
John W
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Big reward this weekend. After a monumental amount of dithering around, I got the hole patterns laid out for the interplane strut fittings and so was able to do a preliminary rig of the wings to check how square it all was and the parallelism of the struts. It sure does fill up the workshop.
So now it comes back apart to do the covering. Lots of small chores and checking before that happens, but it's encouraging that it looks pretty good and square. #^
We had a really nice day in Seattle yesterday, so I drove down south and met up with Steve Helmick, Dane Covey and others for a morning of stunt practice and blowing cobwebs out of the brains and motors. Everybody took home their airplanes in immediately reusable form, so it was an excellent day. It was my first flying since before Thanksgiving and it was really nice to get the tug on the end of the lines.
John W
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No, no, not too nice to fly, not nearly as slick as those hot-dog PA planes that go plunging at the pavement. Actually there is a 1/6th scale race of humans that I've hired to build it. The whole thing is run by Capt. Eddie. I caught a sneak shot of him climbing in to check out the cockpit. HIHI%%
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Capt. Eddy must be a Secret Service alias, cause that sure looks like ex-president G.W. Bush to me! H^^
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Boy John, every time I come to check on the progress of this miniture scale model it blows my mind what you have done. You sure you didn't hir some witch doctor to shrink down a real Jenny? It is awesome the work you are putting into this project and wish I could be there when you fly it. n~ %^@
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This past weekend was rainy and mostly an inside weekend. I was able to get all four wing panels covered as well as a few other small chores. The covering went fairly smoothly, the only variation being that the Top Flite iron I use had to be turned up to the max when I was sticking the Solartex to the aluminum tubing used for the tips and wing root curves. This was also true of the previous work on the stab, rudder and elevators. The aluminum tube has to be warmed up enough to allow the glue on the Solartex to adhere. In one spot at the wing root where the tube has an acute angle to the line of the fabric, I ended up gluing it on with CA.
I was also able to prepare the airplane end of the insulated flying wires, crimping on the wires that carry the control signal into the plane and also crimping on the tubing loops that forms the ferrule. All in all a pretty productive weekend.
The next chores are to do the rib stitching and covering tapes, then I will be set to paint the circles and stars and attach the strut fittings. Boy, then we'll be ready to have some real fun: the wire rigging. I've actually been looking forward to doing that part, it's one of the premier features of a Jenny.
The pictures show a couple of the steps, using the brass plates to predrill the screw holes for mounting the strut fittings, and the one of the fitting assemblies on the bottom of the upper wing. The strut fitting are built up of several of the Proctor brass parts to duplicate the combination fitting that the full scale plane uses. It's a very contrasty photo, and it's hard to make out whats going on. The pulley on the right is for the aileron control cable.
Anyone who wants more info about any of these processes, let me know and I'll post more. I don't want to bore anyone with obvious details.
Regards to all, and best wishes for a speedy recovery to Art Adamisin. It's good to hear he's home.
John Witt
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John,
Where did you the 1/6 scale pilot who is climbing aboard??
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Tom,
It is a collectible doll of Eddie Rickenbacker, imported by Sideshow. If you search around you can find them for sale with prices all over the map. I paid $25 plus shipping for mine a few months ago.
http://www.sideshowtoy.com/?page_id=4489&sku=41141
John W
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John,
Thanks for the info.
Following your "Jenny" progress is like absorbing knowledge. No matter what event we fly, we can all learn from the methods and techniques used by others. Personally, you and Allen are doing much to give me even more appreciation of the efforts of scale modelers.
Thanks for the lessons from a true master modeler.
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A quick update. The last week or so has been occupied with sorting out the strut fittings and doing the rib stitching and tapes. The last panel is nearly done, there are around 1200 little glue lines to simulate the rib stitching and 62 tapes covering them. I am glad this is almost finished -- I've had about all of this kind of fun I need. The stitching and tapes are such a prominent feature of the plane that it would be impossible to leave them out and have it look right, but it has grown a bit tedious.
I have a lot of admiration for Allen for actually stitching the covering, how cool. Metal airplanes have their panel lines and rivets, fabric airplanes have stitching. It's all part of the patina.
Next will be the installation of the last of the fittings to the upper wings and then all the wings can be fitted to the fuselage and the rigging started. I'm looking forward to that part.
John W
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Wow....talk about patience! Really enjoying your build. Thanks so much for taking the time to post it. H^^
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The weekend's work produced some progress. The star insignia are now finished on all four wing panels, so I could then attach the end fittings for the brace wires. The next step was to install the first part of the rigging which is the upper wing trusses, and then start mounting the wings to the fuselage.
The wings are braced so that they can be removed from the fuselage for transport, so the first bit is to get the spar end fittings lined up and temporarily pinned in place. Then the interplane struts are added and after all the screws are tight and trimmed, the the brace wires can be installed. I have the right side wings attached, the left side will be next and then I plan on taking the plane upstairs to the living room and rolling back the carpet to use the floor as a surface plate to check the alignment.
John W
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then I plan on taking the plane upstairs to the living room and rolling back the carpet to use the floor as a surface plate to check the alignment.
I have used the living room many times for putting planes, motorcycles, and what ever other kinds of toys I have had together.
It looks absolutely beautiful!
Thanks for all of the pictures throughout the build. I have learned a whole lot from just looking at your pictures.
Thanks
David
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John, you have way more patience than I ever had. It's late now, but instead of crimping, did you think of swagging the ferrals. #^
David, did Mom really let you build in the living room? When you see her, tell her the Old DOC says hi. H^^
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Big milestone this time. All of the rigging necessary to fly is finished. I still have to do a final alignment check and then safety wire all the turnbuckles and a dozen other small things, but it is really getting close to flight time. I'm starting to salivate like Pavlov's dog at the prospect. Here's a few shots from this evening (3/4/10).
John W
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I cant tell you how much this rocks my boat.
really solid job, just be patient with the test flights man,,
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Really nice! y1
If all goes well will you bring it to the NATS? If so what class will it be in? Looking forward to seeing it first hand. Thanks for sharing it with us.
H^^
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Thank you all for the kind words. Don't know about the Nats. I'd like to go just to meet all the good folks and see all the wonderful airplanes. I am still working for a living so have to figure out if there will be enough available vacation time. I'm also the lead mechanical engineer on a project that may not allow me to be gone in that time frame. The last time I attended a Nats was at Willow Grove NAS in (I think) 1958. I guess it's time to do it again. #^ Mainly I just want to get through the Northwest Regionals in one piece.
The class for the Jenny is Sport Scale, since it is a kit airplane and is from the Ralph Beck plans. Doc, I borrowed a friend's Nicopress swaging tools, but it didn't go small enough for the ferrules on the rigging. I was able to use it to do the leadout wires. I used an old dull pair of side cutters to put two transverse crimps in the ferrules which holds the .015 rigging cable to the breaking point. In addition the crimps work better than just mashing the ferrules flat because crimping avoids a sharp stress raiser at the end of the ferrule which could cause the cables to break.
Regards to all,
John W
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If not for the backgound clutter, I would have sworn that was the real plane, picture taken froma balcony. That is one project you can be pround of and to do it in such a short period of time. Hope it flies as well as it looks. #^ #^ #^ H^^
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Clutter! Doc, That's all good stuff. A clean shop is sign of a sick mind... LL~ LL~
John W
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John
You can enter it in FAI F4B this year at the NATS. The only event it would not qualify for is Designer Scale and Profile unless you accidentally drive over it. LOL
Clancy
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Clutter! Doc, That's all good stuff. A clean shop is sign of a sick mind... LL~ LL~
John W
You mean I may be sane after all? #^ #^ n~ :P D>K H^^
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John,
Make sure you test fly it before you bring it to the regionals ok?
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Oh yeah, for sure.
My plan is to be airworthy by the end of March. It is almost ready now, just down to the control system, handle and final checks. Due to other commitments, I can't fly on 20-21st, this coming weekend has bad weather forcast, so maybe on the 27th.
I'd like to have enough flights in April to get it trimmed and practice the maneuver schedule. We'll see, the weather is being kind of fickle right now.
John
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John
Be sure to have someone taking lots of pictures before, during and after the test flights.
Clancy
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The forecast shows a weather window opening this coming Sunday. I finished terminating the lines and checking out the controls last night. Probably will get to Arlington Airport around 10AM. First flight around 11AM. If not this weekend, the next opportunity is two weeks away.
If anyone's in the neighborhood, come on by. Should be interesting, one way or the other. S?P
John W
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The Jenny flies. Made a couple of 6 minute flights, with touch and go landing, high flight and missed approaches. The power level is just about right, with 10 second laps at roughly half throttle. Clancy's throttle control works great. Conditions were overcast, calm to light winds and about 50 deg F. All the electrics stayed nice and cool. #^ #^
Pictures shortly, and maybe a video if I can figure out how to post it.
Now on to some more detail work.
John W
Pictures added -- photos by Brian Taylor, who is building an R/C Proctor Jenny
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Congratulations John!!!
Now you just need some more practice time.
The Regionals would be good practice time working under actual competition conditions.
Remember High flight scores zero below 30 degrees, some points between 30 and 45 degrees, maximum points above 45 degrees and zero if you crash because of flying too high (above 60 degrees)!!! Ask Steve Couch!
Will be watching for you at the NATS.
Clancy
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Way to go John y1
Chuck
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Atta boy! Looks very real in the air......so real it looks odd without the pilot in there flying it! H^^
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Glen
The pilot was there, but he bent down to get his cigar that he dropped just as the picture was being taken. LOL
It is a great looking model.
Clancy
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You can be very proud of yourself to tackle such a project and finish it in such short time. Of course I have heard that scale models are never finished by a couple of gents that used to fly scale out in western Kansas. Just don't bruise the grass with it. By the way the in flight shots are great. #^ #^ #^ #^ #^ H^^
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That's exactly right, John, it's not finished. I have a full page list of stuff to be done before the contest in May, not the least of which is to get Capt'n Eddie aboard. Even with all that, the cockpit details are not likely to be in there. Maybe by fall. I've got to get in some stunt practice too.
The Jenny is a great flyer, I can't wait to get it airborne again. One of the two Turnigy batteries I bought has a bad cell and won't charge, so I've got to get another battery. I guess that's why they're cheap!!!
John W
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Well done John,,
LOve the finished,, well how about love the "at this stage of completion" model,
always loved the old bird, you did her proud.
looking forward to seeing it at the regionals....
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Hi John,
Very well done! Glad to see it airborne, it looks good out on the end of the lines in those pics. Good luck with it, hope to see you at the nats.
Chris...
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Thank you all. I hope to get some more flying in soon, maybe Saturday if the weather is as forecast. I was gone over the last weekend, so nothing happened, but in the last couple of evenings a few things were accomplished.
The numbers are now painted on both sides of the fuselage and the hinges and fairing strips are in place on the turtledeck. The real Jenny's turtledeck is held on with 8 brass cabinet hinges with cotterpins inserted where the hinge pins go. It's possible to easily remove the turtledeck for maintenance.
The hinges are made of .020 styrene, with a small strip of styrene half-round glued in the middle. These were painted brass and glued on with CA. The fairing strips are likewise Evergreen .010 x .188 wide strips, painted Olive Drab to match the cowlings and glued in place. Here's a picture of the results. Should look OK from 15 feet away. #^
Regards to all and thanks for the encouragement
John W
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Very cool. I hope to see it Saturday.
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Wow, John, what a masterpiece!! I'm so glad to learn that it flies great - and I sure hope you are able to attend the nats with it. Your time frame for the build challenges me, big time!! y1 y1 y1
Blessings,
Will
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Great job John, looks good on the ground and in the air. Hope to see you at the "Nats" and the FCM the last of Aug.
Blessings
Allen
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Very well done.
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I bet it looks good from lots closer than 15 feet!
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How far away is the real plane you are replicating? That is still awesome. #^ H^^
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John,
The plane being modeled is a generic JN4-D2, production model, based on the Joe Nieto drawings that appeared in Model Airplane News.
S/N 2508, the plane which is depicted in Nieto's drawings is now in the Air Force museum at Wright-Patterson AFB. 2508 has been repainted by someone, somewhere along the line in solid olive drab, so no longer has the Air Service Mechanic's School markings as shown in the drawings. Incidentally, I clipped those drawings from MAN when I was a kid and have been carrying them around, along with many others, for a long time.
I haven't been able to find much evidence that most JN4-D2s were painted anything except clear dope and varnish, except for the Navy versions which were apparently grey or silver and yellow. Since color film wasn't available, descriptions have to do as far as colors go. Also the film used in those days did not render colors in a consistent grey scale, so estimates from B/W photos are often erroneous. Some late production Jennies were reportedly painted solid OD or Yellow, there were other variations as well. There is also some confusion about color since the varnish used would turn yellow/brown pretty rapidly.
My model carries serial number 2722 which was very close to the 2508, so I'm making the somewhat cavalier assumption it would have been at Kelly Field at about the same time. I found a list of all the early Army Air Corps serial numbers on line. I didn't want to use 2508 because it has been done many times. My model combines details from research, the Nieto drawings, archival Jenny photos and many photos of the Daughtry Jenny at Golden Age museum, the Jenny at Flying Heritage museum and the Jenny at the Hood River Oregon museum, as well as some photos of Jennies under construction in the Curtiss factory. Also had some correspondence and phone conversations with the Flying Heritage curator, and the gentleman that did the actual restoration work on that airplane, and not least, Brian Karli's website showing his construction of a full scale Jenny from Curtiss blueprints.
Hope this sort of answers your question.
John W
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John,
hope your scale documentation package supports the serial number you used. Might make a difference come judging time.
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Got in three flights today totaling about 30 minutes. It is a lot of fun to fly, especially touch and gos.
Here is a link to Brian Taylor's pictures of the first flight:
http://cid-15550321b698223e.skydrive.live.com/browse.aspx/John%5E4s%20Jenny
And a picture from today.
Got to get to work on the documentation package, plus some more details. I think I have the S/N covered.
John W
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If I didnt know better I would swear that is real!
Great job!
David
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John
Look great and I really like the shot with the two pine trees in the background. It looks like he just buzzed his girlfriends house and just missed the trees.
Clancy
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Control lines -- well, it looks as though I read the wrong column in the AMA line size table and the Jenny will require .021 diameter wires. The wires I've been flying with are .018. Brodak doesn't carry anything bigger than .018 in insulated wires, so I went internet shopping and found nylon coated fishing leader cable that will work. Jenny came out a bit over 10lbs weight, so requires .021 wire. That means a 50 lb pull test.
A local tackle shop had the right wire in stock, and sold me 150 feet for $14. It also turned out that they carry crimp ferrules (sleeves) like the ones Proctor includes for making up the wing rigging. I have replaced several of the wires on the Jenny as the rigging settles into its permanent configuration and was running low on the sleeves. The tackle sleeves are annealed brass, black oxide finish, so look just right. They are $1.69 for 36 sleeves -- what a deal!
Incidentally, it required a bit of legwork to figure out which wire to buy. The fishing folks go by the OD of the wire, which includes the nylon coating. What you do is go by the test strength, so .021 bare wire is 60# test, and the nylon coated .021, also 60# test, is actually .032 in diameter.
John W
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.032 will be a heap of drag. Maintaining control in the wind could be sporty. Also, nylon coating tends to snag on leadout guides. Want to try painting some plain .021s?
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Might be worth a try. Maintaining control in wind is going to be sporty anyway. I initially started with about 1/4 inch of rudder offset and a very small amount of up aileron in the OB wing. Jenny ailerons are LARGE. After the second flight I took out all of the rudder offset, because of lots of yaw, without making a lot of difference in the line tension. So far there isn't any noticeable friction in the controls, unless the nylon is wet and then there is a great deal of friction, too much to fly with.
I have about 2 oz of tip weight in the lower wingtip and with that it flies pretty level, with the 70 ft .018 lines. I could also reduce the line length some as well. The .018 coated wire is .028 in diameter.
Another possibility is to go with one insulated line, though it has been suggested that this leads to an elevator trim offset from the differential drag. There is a large variation in pull between the upwind and downwind side of the circle even in the very light breezes so far. Flying faster fixes that, but looks less realistic.
I don't know how much insulation it takes to avoid interference in the control signal, probably not much, since I think it is just 5V. I also don't know what the consequences of a short are. Perhap Clancy could comment on that.
BTW, in calm conditions it will fly very slowly, about 20 mph.
John W
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.032 will be a heap of drag. Maintaining control in the wind could be sporty. Also, nylon coating tends to snag on leadout guides. Want to try painting some plain .021s?
I had thouhgt about trying to coat my own line to make insulated lines. However I changed my mind. The life of my aircraft depends on not getting any shorts in the lines. Where talking big airplanes that should handle the load. By the way my leadouts are not insulated. They can not touch so they don't need to be insulated. Just my $.02 thought on the matter.
H^^ D>K
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Good point. I was wondering what the loss-of-signal effects are on the Jenny. If they are benign, we could do something flaky like trying to coat the lines ourselves (I am sorta volunteering to conspire). You can't count on it being dry or calm in Eugene.
I, too, was hoping for a Clancy comment.
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I use a converted R/C system, but a short leads to total loss of control(well except for elevator). Been there, done that, wrecked my Hs-129 at the 2003 Team Trials, engines shut down and the gear and flaps stayed up. Took me a long time to find the short (intermittant of course). No telling what your throttle would do.
I have had better results adjusting line pull by moving the leadout guide.
Since drag varies with the square of the speed, it is not quite the problem with a slow scale model that it would be with a stunter or combat model. I fly my Val with .027 + coating because I had it; it flies good enough to place first in the only two contests it has entered.
Chuck
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I do not reccomend using one insulated line. You suggested that only one line needs to be insulated. I started out with only one line insulated and lost an aircraft because of this. What happnes is that when you go low throttle the line tension reduces. The larger insulated line has more drag and tends to pull the ship in this direction. I had the single insulated line on the up side of the controll. It was a windy day. I cut power and as the aircraft came into the wind the drag on the up line up line drove the airplane up and over the top - SPLAT! If you use only one insulated line on a two line system twisting the line some may help. I have not tried this but it may help. To be safe I would use two insulated lines to keep the line drag the same. Interesting enough the insulated lines that Brodak sell, both lines are insulated.
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Gentlemen
You do not need me to comment. John has the hard earned lesson about using only one insulated line. I have never flown with only one insulated line. I have painted a set of lines to try this summer but no comment until I get several flights in on them.
If you have the lines spaced you could fly with uninsulated lines if you are not doing aerobatics. The 5 volt maximum is correct on U/Tronics Control.
Twisting the lines using only one insulated sound good BUT enough twists to keep the lines together would make flying very hard to control due to the drag between the lines. Have someone hold the model with mixed lines and see how the elevator functions with several twists in the lines.
I ran the software "Line III" on the Ringmaster Trainer I built last year and when going from plain to insulated I had to move the line guide back 1/2 inch. The Ringmaster Trainer weighs 40 oz. You might want to try using Line III to see what the actual effect of line sizes will do on your scale models. I feel the proper line guide position places the wing in the air pointing straight at you. This is how the trainer flies with the line guide as per Line III. Most of my scale models fly that way.
I am hoping to meet many of you in person at this years NATS,
Clancy
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Thanks all,
John, I think you commented awhile back about not using one line, so I hadn't seriously considered doing that. Running Line III show a leadout position of .74 for the .028 line I've been flying with and a position of .82 for the .032 lines which I'll be using. I suspect that difference is lost in the noise for the Jenny. I don't intend to engage in risky flying with this model, it costs too much in money and time.
It currently flies around with little yaw in the location the guide has right now, with nearly zero rudder offset and no motor offset. Line III predicts 8-10 lbs of pull at 10.5 second laps (30 MPH), and I guess that's about what it has -- a substantial pull.
Interestingly, the Jenny will rock its wings as it passes through air turbulence, but that doesn't seem to affect the pull much. One does not want to get too slow on the upwind side of the circle however, which complicates trying to do a scale-like takeoff and climbout. The real Jenny has a miserable rate of climb, about 200 ft/min, so it should take a lap or two for the model to get to a six foot cruising altitude. One thing you would not want to do is lose power at the wrong time, the Jenny glides like a rock.
Painted lines would probably improve things, but frankly I don't intend to fly it in much wind. The Arlington, WA airport site I usually fly at has a lot of fairly calm weather, so I should be able to enjoy the Jenny a lot.
John W
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One more silly suggestion -- use 3 lines, two uninsulated ( use both for return ) and one very small insulated line. Probably would have the same drag as two insulated lines and would be more hassle than it's worth. Rember the engineering # one rule -- KISS - Keep It Simple Stup------
n~
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Yes the Jenny does fly slow. Looks like you could walk faster. The only oe I seen in the air was back in 69 or 70 when on the way to a Wichita KS constest. It was coming in for a landing northbound over Kansas Turnpike. Looked to be about 100 feet high and was barely moving. It is one graceful looking plane in the air. Just don't push yours that hard. H^^
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Had a nice flying day today at the Arlington Airport. PW showed up to test his very impressive new airplane, and Rick Cochrane was there as well with his Impact.
Two of the local Proctor Jenny builders also showed up to see my control line version (they fly RC), Brian Taylor and Steve Kessinger. Steve, the madman, is building two of these at once. Very pleasant company and flying models on a beautiful day. It doesn't get much better.
And on that note, I am going to close out the saga of building the Proctor Jenny. There's not much left anyway but a few fiddly cockpit details. It's been fun writing about it and the many kind remarks and suggestions from you guys have been greatly appreciated. You're all the greatest.
Best regards,
John W
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How did you get your pilot to grin like that? ;D Superb model and photos by the way!
Cheers Neville
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Thank you for all the pictures and comments during construction. I would say that would be as hard as building such a beautiful airplane. y1 y1 I noticed the pilot has no helmet as I can see, so how does he keep his hair combed. LL~ LL~That is one beautiful in flight shot. That looks so real. H^^
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The Jenny was awarded first in Sport Scale at the NW Regionals. I was lucky to have perfect weather and was even able to get in high flight. The maneuver sequence was engine start, takeoff, 10 laps level, high flight, touch and go, landing and engine shut down.
With little to no wind, I could fly it slow enough to get a very realistic flight: almost a full lap of takeoff roll and a very gentle climbout, with no worries about a nice slow approach to touch and go and landing. Great fun!
Pat Johnston and Mark Scarbourough were the judges. They worked very hard in the static judging to go over the 5 scale entries in about 3 hours.
Clancy's throttle system worked very well.
John W
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John
It was a pleasure to judge, I have always had a soft spot for scale. I keep threatening to build one of several airplanes I have in mind, but then, who would be left to judge lol.
Glad you enjoyed your time in Eugene. I wish I could say that you worked diligently to fight it out for first place in sport scale, winning by grit and pulling out the few points in the last minute, but, well,, it wouldnt be true, you were very well prepared, presented your model and documentation well, and frankly, it was pretty much an easy choice. The other entries were interesting, one gentleman had low static scores, but flew his models well, the other had high static scores but had some flight issues sadly, but, no broken models,,
Again, look forward to your additional details on the Jenny, enjoy this great model. ( Oh and I PROMISE Pat and I never ever got closer than 15 feet to judge it,, or uh,, ok so AFTER we judged it we did, but thats ok right?)
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Pictures and meet report at:
http://flyinglines.org/nwregionals.10.html
JW
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John, you can be very proud of your accomplishment. The pictures of your Jenny really make it a stand out. Are you going to the NATS with it? Congradualations on the win. H^^
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I wanted to add, as for the flight, there was a light breeze in the morning, Pat and I talked with John ( read that as arm twisting lol) to add high flight to his manuever list, mostly cause we wanted to see it fly over our heads,, what a totally romantic sight that Jenny made flying overhead with the sun shining through the fabric, all the ribs highlighted,, it was cool. The other thing about watching it fly, it was very scale like in that the breeze would gently rock the wings as it flew. John flew it at a very convincing speed, I think he said it was less than half throttle. GOOD choice
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Thanks for the kind comments. The Nats are probably not in the picture, as I can't afford the vacation time (at least right now) -- maybe next year. It takes 3 days to get there each way (2600 miles), plus the four days of the event and roughly $1K for fuel and hotels. And the wind blows in Indiana...
John W
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John,
A stunning model, beautifully built, a well deserved contest result. Incredibly impressed!
Kim.
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Hi John, Beautiful model of a classic plane, outstanding. I was wondering what size bellcrank did you use of this mod el? Thanks, Mike #^
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Thanks for the compliment, Michael
The bell crank is scratch built from two pieces of circuit board material. C-C on the leadouts is 3 1/2 - 4 inches, don't remember which at this instant. Pictures at Page 1, reply #35 and #48.
The leadout cables are reinforced with 3/32 copper tube which is wrapped around Delrin discs. Each disc has a short 4-40 screw as an axle. 8-32 screw for the bell crank axle mounted in 1/4 6-ply plywood
The hard part of this was figuring out how to feed the bell crank loads into the fuselage longerons. The pull test load is 50 lbs. The spruce crosspieces are backed up with 3/16 square carbon fiber tubes. The whole thing has worked well so far and is very free.
Regards,
John
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John, here's an optional maneuver that you may want to practise with your Jenny. %^@ ;D ;D
http://www.oshkosh365.org/ok365_DiscussionBoardTopic.aspx?id=1235&boardid=147&forumid=180&topicid=5584
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That's pretty cool to see. Don't think I can get a little robot to do that, but it would be fun to have two Jennys going around together!!
Thanks,
John