stunthanger.com
General control line discussion => Open Forum => Topic started by: Paul Taylor on November 15, 2006, 05:18:42 PM
-
I am going sheet the LE up to the spar. Can someone tell me the best way to do this?
Wet the wood and then wrap it around?
Also I am going to put adj lead outs on the end and would like to use the kind that has the brass gromets. Can someone post a few pictures on how to do this?
Thanks
Paul
-
Hey Paul,, My wife bought me a small steamer at Wally World. It Looks like a small vacuum cleaner with a hose. Anyway, I steam the wood on one side and it curves itself in a nice arc. I stack all 4 of the pieces togeter and put a few light rubber bands on them to hold in place while drying out. Makes sheeting leading edges a lot easier for me.
Lee TGD
-
Paul,
Unusual leading edge arrangement... an original?
Most leading edge sheeting is not too stiff to bend gently to meet the spar and ribs, although misting water on the outer surface may help.
I usually build wings with some LE 'step' above the rib outline to butt the front of the sheeting into. Or, for another way, I've sanded the LE strip so the sheeting can lap smoothly onto it. Both ways provide decent gluing area.
If that helps, great.
By the way, brace the wing some way so you don't build in a warp as you apply the sheeting. Also, try to get top and bottom on within, say, the same evening, so that you can get it straight/unwarped.
Somewhere else in here, I think, I outlined how I use yellow carpenters' (aliphatic resin - Titebond or Elmer's work) to iron on LE sheeting. If you find that post, it might offer some ideas...
Luck!
-
Paul,
The wing in your picture is not a good candidate for sheeting back to the spar because there is not enough glue surface exposed on the leading edge. Generally you want to use square stock (1/4 in.) for the leading edge as this gives you gluing surface top and bottom.
However -- if you glue the sheeting to the spar and let that set -- then trim and glue the rest of the sheeting along the ribs and forward to the leading edge you'll be o.k. Only thing is you'll have an edge to edge glue joint on the leading edge instead of a surface to surface glue joint.
To get the wood to bend easily around the ribs curved surface -- spritz it with Windex and it will become amenable to the bending. Tape along leading edge till glue is set.
Here is a drawing of an adjustable leadout guide (the way I do it anyway)---Part 2 slides along the slot in part one. The pinch created by tightening the 440 screw holds the guide where you want it.
-
;D **) ;D AP^ AP^ AP^ AP^
-
Paul: Frank is right that type wing isn't really meant for LE sheeting. One thing you might consider is making some half ribs instead of sheeting. This will help when you go to cover the wing.
-
Paul,
Unusual leading edge arrangement... an original?
I think it's not original, Lou, just uncommon. I built several kits in the '60s that were similar. Wasn't the Omega set up that way? With LE and TE glued to a center piece that tied motor mounts and B/Cmont to the rest of the wing?
-
Not so unusual...
--Ray
-
Thanks guys this helps!
My flying buddy has built this wing and I bet you can drive a nail with it.
Thanks
-
Hi Paul;
Back in the Stone Age my Father used to roll indoor f/f fuselages using a 1/3 amonia to 2/3 water solution. Don't know exactly what it did but it made the balsa bend like it was rubber. He just applied it to one side and the rest was history.
Bill Gruby y1 y1 y1 y1
-
I've sheeted a whole bunch of combat planes akin to this. Get some light, A-grain, 1/16" balsa. The grain is important. You don't need to steam or wet it. Glue it to the spar, then bend it down to the LE, gluing it to the ribs and LE. Start in the middle of the wing, working your way to the root and tip. CA is the easiest glue to use, but I've used (with pins), Ambroid, Titebond, epoxy, and polyester resin. You might think about how to hold the wing while you're sheeting it to keep from building in a warp.
I'll find some pictures of the grommet leadout guides. They're easy to make and last a long time.
-
Hi Paul;
Back in the Stone Age my Father used to roll indoor f/f fuselages using a 1/3 amonia to 2/3 water solution.
Bill Gruby y1 y1 y1 y1
The ammonia is the active ingredient that makes the balsa pliable. Windex has ammonia in it and it's always in the cupboard under the sink.
-
Thank-you--------I always was in awe when he bent 1/16 balsa around a 3/8 brass arbor without breaking it--------now I know the reason.
Bill Gruby y1 y1 y1
-
Paul,
If you can get the wing jig it would be a snap to put the sheeting on liek Howard mentions. It would also ensure the wing stays straight.
-
Thanks Howard!
-
Pul,
I sure hope you post a picture of your sheeting job, I for one would like to see what comes of it. #^
-
Paul,
(snip)
Here is a drawing of an adjustable leadout guide (the way I do it anyway)---Part 2 slides along the slot in part one. The pinch created by tightening the 440 screw holds the guide where you want it.
Hi Frank,
If you add a Sig eyelet (1/8th"od X 3/8th" long) in each of the holes for the lead outs to pass through, they will ride in the slot and keep the guide from twisting.
-
Here (if I can figure out how to post it) is a picture of an eyelet-type leadout guide. Take two pieces of 1/8"-thick basswood about 3/8" wide and 2'' to 3" long and two pieces of 1/32" plywood about 3/8" x 1/4". Sandwich the plywood between the bass pieces at each end of the pair of bass pieces. Poke a series of 1/8" holes through the slot 1/4" apart. Surprisingly, the eyelets stay put until you pull them out to relocate the leadout wires. After a year or so, the holes get a little loose. Then you put a piece of paper towel over the hole when you push in the leadout guide eyelet. The paper towel acts as a shim to keep the eyelet snug in place. Tear off the excess paper when the eyelet is in the hole. I got this design from the Impact plans. I have seen airplanes using this leadout guide with hundreds of flights on them and with the leadout position changed every half dozen flights or so. It's quite reliable.
-
Here (if I can figure out how to post it) is a picture of an eyelet-type leadout guide. Take two pieces of 1/8"-thick basswood about 3/8" wide and 2'' to 3" long and two pieces of 1/32" plywood about 3/8" x 1/4". Sandwich the plywood between the bass pieces at each end of the pair of bass pieces. Poke a series of 1/8" holes through the slot 1/4" apart. Surprisingly, the eyelets stay put until you pull them out to relocate the leadout wires. After a year or so, the holes get a little loose. Then you put a piece of paper towel over the hole when you push in the leadout guide eyelet. The paper towel acts as a shim to keep the eyelet snug in place. Tear off the excess paper when the eyelet is in the hole. I got this design from the Impact plans. I have seen airplanes using this leadout guide with hundreds of flights on them and with the leadout position changed every half dozen flights or so. It's quite reliable.
Good stuff!
Thanks for sharing, Howard!
-
Hi Frank,
If you add a Sig eyelet (1/8th"od X 3/8th" long) in each of the holes for the lead outs to pass through, they will ride in the slot and keep the guide from twisting.
I actually use the Brodk leadout guides now-a-days----all that is taken care of.
But you are most right about the Sig eyelets.
-
This works pretty well...
Phil
-
This works pretty well...
Phil
BINGO!!!!
Thanks Phil, this is what happen when I put the sheeting on.
Going by the hobby shop to get more wood today.
And thank you Howard. Looks Kewl.
Whew!
-
Here (if I can figure out how to post it) is a picture of an eyelet-type leadout guide.
Very neat idea. Thanks for sharing
-
Here (if I can figure out how to post it) is a picture of an eyelet-type leadout guide. Take two pieces of 1/8"-thick basswood about 3/8" wide and 2'' to 3" long and two pieces of 1/32" plywood about 3/8" x 1/4". Sandwich the plywood between the bass pieces at each end of the pair of bass pieces. Poke a series of 1/8" holes through the slot 1/4" apart. Surprisingly, the eyelets stay put until you pull them out to relocate the leadout wires. After a year or so, the holes get a little loose. Then you put a piece of paper towel over the hole when you push in the leadout guide eyelet. The paper towel acts as a shim to keep the eyelet snug in place. Tear off the excess paper when the eyelet is in the hole. I got this design from the Impact plans. I have seen airplanes using this leadout guide with hundreds of flights on them and with the leadout position changed every half dozen flights or so. It's quite reliable.
Hi Howard,
Thanks for posting that picture! That method is one that I use a lot and I love the way it works. A whole lot of I-Beam Classic planes are perfect candidates (along with about any other plane that has the wingtip size) for this style. I put the holes a *little* closer than 1/4", though. ;D
-
Here (if I can figure out how to post it) is a picture of an eyelet-type leadout guide.
Please excuse my stupidity but this adjustable leadout thing is completely new to me. I understand how the eyelet thing works, but my question is this. The picture appears to be near the leading edge of the wing. Is there a similar set of holes farther back on the wingtip or do both lead outs come out that close together?
-
From what I have been told lead outs should be about 3/4" to 1" apart at the tip.
-
Keith,
If you build from a kit or plans, you have the benefit of where the designer liked them. Most times having fixed leadouts in that position will do an adequate job.
Adding adjustable leadouts allows you to fine tune your airplane for best actual position. This position will change slightly if you try new line length or diameter, new engine thrust line, rudder, etc.
If adding adjustable leadouts to a plane that shows fixed leadouts on the plans, I would center on the stock adjustments and allow for a little movement either direction...at least that's the way I do it.
Better flyers may offer better explanations but this is the simple version.
By the way, I remember reading a comment from George Aldrich that before adjustable leadouts he had been known to cut into his plane to make adjustments.
George
-
"The picture appears to be near the leading edge of the wing. Is there a similar set of holes farther back on the wingtip or do both lead outs come out that close together?"
That's the only set of holes. Now you have me worried that I don't have enough. Typically I keep them one or two holes apart: that's 1/4" to 1/2" spacing.
-
Thanks a lot to all of you that explained it to me. Betwen what you have told me and the line calculator that I finally got figured how to run, I think I have a pretty good handle on it (no pun intended).
-
Gents - this is the method I've been using for years and it's about foolproof. j1
I always build my wings in two halves, joined at the center.
This is how I did the Cardinette wing.
Make up two end blocks as shown.
Slide the ribs onto carbon fiber arrow shafts. (holes should be previously drilled in the ribs.)
With the ribs properly spaced, clamp the shafts down to the end blocks.
Glue on the trail edge strips.
Stand the blocks up vertically.
Note that I DO NOT USE a lead edge spar. Being so close to the neutral axis, it contributes virtually nothing.
Now, make up some 1/16 planking that will go all the way around the nose of the ribs, extending back around 1/4" past the spars.
Soak the planking in HOT water for around 1/2 hour.
Take it out of the water and blot it dry.
Gently coax it down over the ribs.
Starting from the middle, tape the planking down, attaching the tape to the shafts.
Let it dry overnight, remove the tape and you will have a perfectly formed lead edge.
Glue it on, trim it and that's it.
Remove the shafts and do another wing.
Align and join the two halves, put on the capstrips and you're ready to install the controls.
Once you've tried this, you may want to do all future wings by this method.
I made the entire Cardinette wing in four evenings. **)
By the way, the next CL World will have a complete article on the Cardinette, outlining this same procedure.
Bob Z.
-
Here's the finished airframe. The wing is absolutely straight.
Bob Z.
-
That's like a lost foam wing without the foam jig. Good idea!
Willie
-
A real plus with this method is the fact that no special equipment is required.
About the most sophisticated tool is a simple drill press. n~
Exacto #11 blade
drill press
two arrow shafts
screwdriver
some screws
glue
tape
a few pieces of pine or basswood for the end blocks
flat surface to work on.
By the way, I make ALL my ribs with the "stack and sand" method
When I join the two halves of the wing, I reinforce the joint with carbon fiber and fiberglass.
Bob Z.