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Author Topic: Legacy Build  (Read 64417 times)

Offline Bill Morell

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Re: Legacy Build
« Reply #50 on: February 17, 2015, 06:55:11 PM »
Randy Powell is building a kit? I am stunned.
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Offline Randy Cuberly

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Re: Legacy Build
« Reply #51 on: February 17, 2015, 07:23:37 PM »
I think the only kit I've ever built that didn't have some fairly serious issues was my Collussus from Walter Umland.  That was truly a fabulous kit.  Everything fit and went together exactly as it was supposed to, and the wood was obviously very carefully selected for it's intended job.

All the kits I've built from other suppliers have had some issues.  Most were certainly not show stoppers but serious enough to delay construction significantly and require modification.  I've had kits with parts missing, holes in wrong places in ribs, supplied balsa that was too thick or too thin for the task at hand (not to the plans), balsa that was warped and twisted so bad it couldn't possibly be used, lazer cut parts that didn't come close to matching the plans, even a pair of fuselage sides that were 2.5 inches shorter than on the plans.
I usually wind up substituting about 25% of the wood for being too heavy or the wrong type for the required job.  Probably the most common error is fuselage formers that are not wide enough to space the required engine, requiring all new fuselage formers to be traced and cut larger.

I have and have built a lot of kits over the years and just about every time I do I say "never again".  The exception is the kit I mentioned above.  Its the only kit I've built from Walter but anytime he makes something I want to build I will have it!

I do realize that making kits is not an easy task and certainly not one that pays very well.  I also do believe that most of the folks that make kits could do better.

I do not believe in singleing out any individual for criticism...trust me they know who they are.  I do believe in singleing out those who deserve praise and Walter is the one that gets that vote.  I only wish he would build more large stunters that are competitive in todays expert environment.

Randy Cuberly
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Offline Tim Wescott

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Re: Legacy Build
« Reply #52 on: February 19, 2015, 03:15:39 PM »
The directions say to sand the leading edge to final taper by putting it between a 3/8" rod and a 3/16" rod -- to get a piece of balsa that tapers from 3/8" to 3/16.  That wouldn't happen -- you'd get something tapered from less than 3/8 to more than 3/16.  I could do it that way, then at the end shrug and sand the ribs a bit narrower -- but nooooo, I'm going to do it "perfect" -- or at least I'm going to get a lot closer.

I ended up fumbling around with rods (7/16 and 3/16) and spacers, to get a TE that's pretty close, although still a bit big on the wide end.  I'll sand it nice once it's glued on.

Here's some CAD drawings showing what you get from using the directions, and what you need to do if you start with a 1/2" rod, a 1/8" rod, and some magic spacers that just happen to be the correct width.
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Offline Balsa Butcher

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Re: Legacy Build
« Reply #53 on: February 19, 2015, 03:49:46 PM »
I have found that using square brass channels (at the K&S rack) work better than rods for that procedure.  8)
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Offline Tim Wescott

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Re: Legacy Build
« Reply #54 on: February 19, 2015, 04:02:49 PM »
I have found that using square brass channels (at the K&S rack) work better than rods for that procedure.  8)

I considered that.  I didn't do it because (1) it fixes the problem at the big end but not so much the small end, and (2) I didn't want to drive to the hobby shop!
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The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline peabody

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Re: Legacy Build
« Reply #55 on: February 19, 2015, 04:31:34 PM »
I always thought that you required three rods to avoid building in a warp.
The leading edge stays constant, while the trailing edge requires two sizes?

Offline Tim Wescott

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Re: Legacy Build
« Reply #56 on: February 19, 2015, 05:23:59 PM »
I always thought that you required three rods to avoid building in a warp.
The leading edge stays constant, while the trailing edge requires two sizes?

Yup.  I did the calculation for both sizes for the "this won't work quite right" example, but not for the "this is how to do it" example.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Bob Reeves

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Re: Legacy Build
« Reply #57 on: February 20, 2015, 02:35:31 AM »
Yep, have to use 3 rods. I use soft steel rods from the hardware store so they can easily be bent to conform to the trailing edge.

Offline Allan Perret

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Re: Legacy Build
« Reply #58 on: February 20, 2015, 06:43:57 AM »
If you have a table saw you can make you own sanding guides from hardwood sticks.  You can sand the same taper into the guide sticks and that eliminates the errors of the rods.  With each use of shaping a new balsa surface I put a new layer of masking tape on the sticks  as a guide to sand just down to but not into the hardwood guides.
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Offline Tim Wescott

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Re: Legacy Build
« Reply #59 on: February 20, 2015, 08:47:38 AM »
If I'd had a table saw I probably would have tried that, or perhaps just whacking what I needed out of the wood that I had, then doing final sanding for smoothness.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Randy Cuberly

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Re: Legacy Build
« Reply #60 on: February 20, 2015, 05:38:33 PM »
If I'd had a table saw I probably would have tried that, or perhaps just whacking what I needed out of the wood that I had, then doing final sanding for smoothness.

Tim,
I think the most important thing here is just maintaining a consistent radius for the LE.  A couple of small radius forms (on sheet) and your eyeball (which is surprisingly accurate if you're careful) can do a really good job.

Randy Cuberly
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Offline Bill Little

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Re: Legacy Build
« Reply #61 on: February 20, 2015, 05:53:41 PM »
Randy Powell is building a kit? I am stunned.

Hi Bill,

I am sure you are aware that Randy is not really building a kit.  He is using some parts from a kit, a set of Imitation foam wings and some parts Pat J cut for him.  So, no, he is not truly building a kit. ;D

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Offline Tim Wescott

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Re: Legacy Build
« Reply #62 on: February 20, 2015, 07:50:45 PM »
I think the most important thing here is just maintaining a consistent radius for the LE.

We're talking about the trailing edge at the moment, which I forgot to put on before I put on the leading edge.  So the build order for this one is inboard LE, TE in & out, then outboard LE.
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The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Allan Perret

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Re: Legacy Build
« Reply #63 on: February 20, 2015, 09:02:27 PM »
We're talking about the trailing edge at the moment, which I forgot to put on before I put on the leading edge.  So the build order for this one is inboard LE, TE in & out, then outboard LE.
My mistake, when I read about using rod method for tapering, I thought you were talking about flaps or elevator. 
For tapering a stick to make TE's, I do that on a table saw also..
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Offline Randy Cuberly

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Re: Legacy Build
« Reply #64 on: February 21, 2015, 12:46:51 AM »
We're talking about the trailing edge at the moment, which I forgot to put on before I put on the leading edge.  So the build order for this one is inboard LE, TE in & out, then outboard LE.

Oh, of course.  Well just modify the build a bit and install the trailing edge sheeting, then sand the back of the TE ribs flat and install a cap, then sand the necessary taper into the cap to comply with the sheeting angle.

I don't believe in tapering flaps for a stunter...it tends to make them too wimpy.  With flaps, the stiffer the better.  I usually cover my flaps with two layers of 1 OZ fiberglass cloth also.  makes them very stiff and really helps in the trimming process as well as making the airplane hold trim better.

Randy Cuberly
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Offline Howard Rush

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Re: Legacy Build
« Reply #65 on: February 21, 2015, 02:43:21 PM »
With flaps, the stiffer the better.

The JCT is coming to town.
We're plenty stiff from the flaps on down.
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Offline Tim Wescott

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Re: Legacy Build
« Reply #66 on: February 21, 2015, 02:48:22 PM »
I don't believe in tapering flaps for a stunter...it tends to make them too wimpy.  With flaps, the stiffer the better.

http://flyinglines.org/dirt.5.09.html.  Search for "flap", read about the flaps on Howard Rush's Impact at the Regionals that year.
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The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Tim Wescott

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Re: Legacy Build
« Reply #67 on: February 21, 2015, 08:00:03 PM »
The first shot is just a trophy shot -- I got the outside sheeted!  Moreover, I was smart enough to fold the ends of my tape over this time -- it came off much easier, without me worrying about digging my fingernails into my nice smooth leading edge.

In the process of sheeting the outside, I realized that some of the glue had let loose where I spliced my sheets together, leading to a crease in the LE sheeting.  I think I was being a bit too economical with the Ambroid, and the stress of the balsa shrinking as it dried pulled things apart.  I was able to mostly correct this on the outside -- but then I discovered that I had the same problem (in roughly the same place!) on the inside LE sheeting, and since that was all glued down in happy ignorance, there's this honkin' big crease sticking out on that side.  So I backed up the crease with little 1" wide strips of 1/16" balsa, in hopes that when I sand the crease away the LE will have enough structure back there that it won't get too warped up.

Sigh.  Screwing up already.  Oh joy.

The second shot shows a nifty way I figured out of holding up a wing, if you happen to have a leading edge buck shuck* lying around.  Not apparent in the picture is the fact that there's about half a pound of steel bar on the wing tip end, holding everything steady.  This holder came in handy for gluing in the afore-mentioned backup strips.

* Say that three times fast.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Randy Powell

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Re: Legacy Build
« Reply #68 on: February 21, 2015, 10:14:43 PM »
Shouldn't this be in the building thread?
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Offline Tim Wescott

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Re: Legacy Build
« Reply #69 on: February 21, 2015, 11:05:03 PM »
Shouldn't this be in the building thread?

If you mean the Building Techniques forum -- I dunno.  I always took that to be a place to ask questions about how to do something, or post nifty new ways to do something.

This is just a story of a particular build.

I figure that if it's in the wrong place, some moderator or another will move it, and if I'm lucky I'll remember the right place to put my next build thread.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Randy Powell

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Re: Legacy Build
« Reply #70 on: February 21, 2015, 11:32:51 PM »
Man, you are so easy.....
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Offline Bill Morell

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Re: Legacy Build
« Reply #71 on: February 22, 2015, 01:28:17 PM »
Hi Bill,

I am sure you are aware that Randy is not really building a kit.  He is using some parts from a kit, a set of Imitation foam wings and some parts Pat J cut for him.  So, no, he is not truly building a kit. ;D

BIG Bear
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Hello Bill, yeah I was just having a little fun with that.  Always enjoyed his builds when he did them back in the day over on SSW.
« Last Edit: February 23, 2015, 10:03:09 AM by Bill Morell »
Bill Morell
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Offline Randy Cuberly

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Re: Legacy Build
« Reply #72 on: February 22, 2015, 05:31:25 PM »
Tim,
Do you use masking tape when you edge glue the sheeting?  Also I like SIGMENT for edge glueing sheeting because it doesn't shrink as much as Ambroid when it dries.

I use the masking tape method and have never had a problem like you show!

Randy Cuberly
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Offline Tim Wescott

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Re: Legacy Build
« Reply #73 on: February 22, 2015, 10:31:08 PM »
Tim,
Do you use masking tape when you edge glue the sheeting?  Also I like SIGMENT for edge glueing sheeting because it doesn't shrink as much as Ambroid when it dries.

I use the masking tape method and have never had a problem like you show!

Randy Cuberly

Hey Randy:

I usually use the masking tape method, but I was seeing if I could improve on it this time.  I don't think my problem was using Ambroid -- it was using Ambroid that was thinned out too much to really work.

Live & learn.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Tim Wescott

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Re: Legacy Build
« Reply #74 on: March 02, 2015, 08:20:41 PM »
I've been flattened by a cold the last couple of weeks, so I haven't gotten much time for fun work, and even less for taking pictures.

The TE wood was, not unexpectedly, bowed.  Balsa warps.  You should never expect a sheet to be straight.  In this case the worst sheet was bowed by a hair less than 1/8", so I sliced a nominal 1/8" off of each sheet, leaving me with sheets 1 3/8" at the ends and nearly 1 1/2" in the middle.  They're glued on so that the straight edge faces in to the wing, and the bowed edge lops over the trailing edge wood, to be trimmed off.

I couldn't get the TE to match the rib taper exactly, and the more I tried the more I messed up the ribs.  So I gave up and just clamped the @#$% out of the TE.  It'll have a wow in it, which I'll mostly sand off, and for the rest -- I'll weep if I lose a contest that gets down to the appearance points.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Tim Wescott

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Re: Legacy Build
« Reply #75 on: March 02, 2015, 08:27:31 PM »
Today's work was whacking a bellcrank out of 1/8" phenolic, and making a pivot.  This will all run on a hunk of 5/32" drill rod, set into the wing per the plans.

The throws indicated on the plans seem wacky to me -- they're calling out using the inner pivot on a Brodack bellcrank (5/8" from center) to a flap horn that's 1.25" from center, and thence to an elevator horn that's less than 1/2" from center.  That just doesn't seem right.  I'm going to set it up so that the flaps move +/- 30 degrees or so with +/- 45 degrees bellcrank movement, and the elevator having, presumably, more (it'll be adjustable, so it'll be whatever I want in the end).

If I stick with the flap horn dimensions given on the plan, that works out to a bellcrank pivot that's 7/8" from center, which eyeballs out to about the right distance.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Tim Wescott

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Re: Legacy Build
« Reply #76 on: March 02, 2015, 09:04:16 PM »
Phenolic sheet is just awesome stuff to have around if you have a bunch of sharp sandpaper that you want to be dull.  It's pretty much just as good as fiberglass and carbon fiber for taking that raspy edge off your sandpaper and leaving smooth dullness behind.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Howard Rush

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Re: Legacy Build
« Reply #77 on: March 02, 2015, 11:29:07 PM »
Today's work was whacking a bellcrank out of 1/8" phenolic, and making a pivot.  This will all run on a hunk of 5/32" drill rod, set into the wing per the plans.

The throws indicated on the plans seem wacky to me -- they're calling out using the inner pivot on a Brodack bellcrank (5/8" from center) to a flap horn that's 1.25" from center, and thence to an elevator horn that's less than 1/2" from center.  That just doesn't seem right.  I'm going to set it up so that the flaps move +/- 30 degrees or so with +/- 45 degrees bellcrank movement, and the elevator having, presumably, more (it'll be adjustable, so it'll be whatever I want in the end).

If I stick with the flap horn dimensions given on the plan, that works out to a bellcrank pivot that's 7/8" from center, which eyeballs out to about the right distance.

I'd calculate the throws.  I'd also move the bellcrank more to get more leverage over the flaps. 
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Offline Howard Rush

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Re: Legacy Build
« Reply #78 on: March 02, 2015, 11:31:44 PM »
Phenolic sheet is just awesome stuff to have around if you have a bunch of sharp sandpaper that you want to be dull.  It's pretty much just as good as fiberglass and carbon fiber for taking that raspy edge off your sandpaper and leaving smooth dullness behind.

Could be a warning that it will put similar wear on things that go in the holes. 

Speaking of phenolic, remind me to tell you the story of the phenolic motor mount pads, the serpents, the Sheriff, and the convicts.
The Jive Combat Team
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Offline Tim Wescott

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Re: Legacy Build
« Reply #79 on: March 02, 2015, 11:55:53 PM »
I'd calculate the throws.  I'd also move the bellcrank more to get more leverage over the flaps. 

I'm going to calculate throws.  I'm also going to measure the actual movement I get from the bellcrank once it's in the wing, and, if necessary, re-think the flap arm length.

Could be a warning that it will put similar wear on things that go in the holes.

Phenolic is a pretty popular bearing material amongst mechanical engineers, so I'm pretty comfortable that it'll be OK.  And the only places where there'll be working metal-phenolic joints is at the leadouts: the BC hinge is aluminum against drill rod, and the BC to pushrod join will be a ball joint.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Tim Wescott

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Re: Legacy Build
« Reply #80 on: March 03, 2015, 07:46:45 PM »
I'd calculate the throws.  I'd also move the bellcrank more to get more leverage over the flaps. 

If I make the flap arm 1.5", it should still fit well in the fuselage, and the flaps should move through about thirty degrees for 120 degrees of bellcrank movement.  I ought to be able to get that much (and it ought to be more than necessary).

Dogleg is calculated.  Oddly, but it works.  I only went as far as calculating flap rotation vs. bellcrank, because your spreadsheet doesn't work for me, so I'm whomping it all up with Scilab.  I'm assuming that leadouts & flap to elevator linkage will take care of itself.  I may do better before the control system actually goes in.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Howard Rush

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Re: Legacy Build
« Reply #81 on: March 04, 2015, 02:22:12 PM »
Dogleg is calculated.  Oddly, but it works.  I only went as far as calculating flap rotation vs. bellcrank, because your spreadsheet doesn't work for me, so I'm whomping it all up with Scilab. 

What matters is leadout travel vs. control surface deflection and d surface / d leadout. 

Tim is a computational elitist and eschews ciphering done with common tools like Excel.
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Offline Tim Wescott

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Re: Legacy Build
« Reply #82 on: March 04, 2015, 07:16:24 PM »
Tim is a computational elitist and eschews ciphering done with common tools like Excel.

I don't find Excel scripts to be user friendly.

The Atomic Zombie Workshop could use a page that would do this, user friendlilly.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Tim Wescott

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Re: Legacy Build
« Reply #83 on: March 04, 2015, 07:17:55 PM »
What matters is leadout travel vs. control surface deflection and d surface / d leadout. 

I know.  I should do that calculation, too.  At the moment I'm telling myself that if it's semi-trickle from bellcrank to flap, then because everything else is semi-trickle and all in one plane, it's semi-trickle everywhere else.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Allan Perret

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Re: Legacy Build
« Reply #84 on: March 05, 2015, 05:52:36 AM »
If I make the flap arm 1.5", it should still fit well in the fuselage, and the flaps should move through about thirty degrees for 120 degrees of bellcrank movement.
120° bellcrank movement ???        You previously said +/- 45° which sounds normal.
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Offline Tim Wescott

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Re: Legacy Build
« Reply #85 on: March 05, 2015, 09:26:35 AM »
Howard said I should design for more.  If the bellcrank moves +/-60 to give +/-30 at the flaps, then in normal flying it should never get beyond +/-45, with plenty or headroom.
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The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Allan Perret

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Re: Legacy Build
« Reply #86 on: March 05, 2015, 10:00:35 AM »
I usually install a hard stop to limit crank to +/-45.  I think round maneuvers require 5-10° control surface deflection and the corners 20-25°.
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Offline Tim Wescott

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Re: Legacy Build
« Reply #87 on: March 05, 2015, 10:27:21 AM »
I usually install a hard stop to limit crank to +/-45.  I think round maneuvers require 5-10° control surface deflection and the corners 20-25°.

I prefer to insure that the controls will freely move well beyond anything "reasonable" without binding.  I haven't felt motivated to put in a hard stop, but if I did it would be at around +/- 60 degrees, and it would just be there to make sure that the controls don't go someplace where they can't be retrieved.
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The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Tim Wescott

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Re: Legacy Build
« Reply #88 on: March 10, 2015, 06:35:00 PM »
Actually cut (and bent, and soldered) some metal!

I'm going to do Walker-style tweakable flaps, which means that you need individual flap horns.  This, in turn, means that the flap horns need to be accurate and stout.

So the flap horns are bent from 1/8" music wire so that -- hopefully at least -- they won't get tweaked by accident.  Rather than just soldering the wire to a hole in the horn, I bent the wire itself, to give the horn more surface area and far more moment arm to work on the wire.  They've got two hinge tubes on each wire so I can space the hinge tubes as far apart as possible for rigidity.  The top two pictures show the result.

I was concerned about getting all the angles right -- the control arms need to be perpendicular to the plane of the flap arms, even while being offset about an inch and a half.  Rather than try to get it all right "floating on air", I made a jig from a bit of 2x4.  The jig holds everything in alignment while I'm soldering it all together.

When I get to the point of making the control rods, there'll be a single rod from the bellcrank to the flap control hole on the left horn, and a rod from the left horn back to the elevator. There'll be a boss on the elevator rod with a screw going to the right flap, set up so that turning the screw tweaks the right flap with respect to the left flap & elevator.  Alan Resinger has an excellent picture somewhere around here showing how he did his -- I'll be copying that.  The only thing that (to my knowledge) I'm really doing different from Alan and Paul is that they put their adjustment on the left, where mine is on the right because I'll be running a muffled slimer, and I don't like the thought of all that oil dribbling inside my nice clean fuselage.

Done right there should be a discrete little hole behind the right wing into which I can reach with a nice long ball-end hex driver and adjust the flaps.

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The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Allan Perret

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Re: Legacy Build
« Reply #89 on: March 11, 2015, 07:38:10 PM »
Quote:
 <<<There'll be a boss on the elevator rod with a screw going to the right flap, set up so that turning the screw tweaks the right flap with respect to the left flap & elevator.  Alan Resinger has an excellent picture somewhere around here showing how he did his -- I'll be copying that.>>>

Tim or Alan Resinger:  Would like very much to see picture of that if you can locate.
Allan Perret
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Slidell, Louisiana

Offline Tim Wescott

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Re: Legacy Build
« Reply #90 on: March 12, 2015, 12:51:59 PM »
Tim or Alan Resinger:  Would like very much to see picture of that if you can locate.

Try this thread: http://stunthanger.com/smf/index.php/topic,24567.0.html
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Paul Walker

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Re: Legacy Build
« Reply #91 on: March 12, 2015, 04:14:09 PM »
There will be a complete article on it in a near future Stunt News.

Offline Tim Wescott

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Re: Legacy Build
« Reply #92 on: March 15, 2015, 06:42:50 PM »
There will be a complete article on it in a near future Stunt News.

So, about the time I finish making all the mistakes on this one and button up the fuselage?
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Tim Wescott

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Re: Legacy Build
« Reply #93 on: March 20, 2015, 04:00:16 PM »
I realized after I got my individual horns built, that whereas a normal flap horn is rigid across it's length, these two flap horns had a significant chance of independently flapping (as it were) around when they were supposed to be holding still.  Rather than just putting mounting tabs on each one and depending on my nice light soft trailing edge to hold them in some sort of alignment, I decided that they really needed to be nailed down to a common axis.

I don't know if this is right, or if it's what the big boys do, but it seems like a good idea to me.  I just soldered a length of 1/8" music wire to the pivot tubes; I'll gouge a slot in the trailing edge to accept the wire, and life should be wonderful.

AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Tim Wescott

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Re: Legacy Build
« Reply #94 on: March 22, 2015, 02:27:48 PM »
Here's the horns glued into the trailing edge.  I angled the crossbar down inside the TE so that I would get full travel -- I figured 30o or more would be enough, and I have discernibly more than that, so I'm happy.

This is all pursuant to getting the bellcrank installed, for which I need to accurately determine the amount of bellcrank tilt I need to make the ball link happy, for which I need to have the horns installed, at least temporarily -- and I can install them for permanent now, so I did.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Tim Wescott

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Re: Legacy Build
« Reply #95 on: March 24, 2015, 06:41:15 PM »
Control system in.

This required much hacking up of ribs for clearance, including removing and reinstalling some of the shear webs mentioned above.  If I were smart I would have installed every other shear web with the thing in the jig -- this would have made it nice and rigid in torsion, while still leaving me with lots of room for cutting ribs apart in situ.

Not shown is the fact that I was a bit stingy with the amount of bellcrank mount that extends out the bottom of the wing.  I'll probably put a bit of extra plywood bracing on the sheeting on the inside, to help transfer the flight load to the outside of the sheeting, to be picked up by the bellcrank pivot brace that transfers the load to the fuselage.

I get to work on this thing in mostly short chunks.  As a consequence, I often end up doing things out of order, or at least in strange orders.  But it's either that or not get it done at all, so I just kinda proceed in all directions at once, and sooner or later a plane comes out.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Gerald Arana

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Re: Legacy Build
« Reply #96 on: March 24, 2015, 07:37:56 PM »
Tim,

I don't know what your plan is but, that thing is going to roll real fast with the flaps in that position!  y1

Might need a bit more reinforcement..... LL~ LL~ LL~

Jerry

Offline Tim Wescott

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Re: Legacy Build
« Reply #97 on: March 24, 2015, 07:45:04 PM »
I don't know what your plan is but, that thing is going to roll real fast with the flaps in that position!  y1

The elevator pushrod will tie it all together, and allow me to tweak the flaps precisely with a long hex wrench instead of the "bend a little, hope a little" method.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Tim Wescott

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Re: Legacy Build
« Reply #98 on: March 25, 2015, 08:53:06 PM »
Totally useless trophy shot of the center section -- but, it's all sheeted!

I didn't quite match the height of the TE sheeting with the center section sheeting, so I'll be doing some filling before the CF veil goes on -- my bad, I need to figure out how to do the job right.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Paul Walker

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Re: Legacy Build
« Reply #99 on: March 25, 2015, 11:41:21 PM »
Totally useless trophy shot of the center section -- but, it's all sheeted!

I didn't quite match the height of the TE sheeting with the center section sheeting, so I'll be doing some filling before the CF veil goes on -- my bad, I need to figure out how to do the job right.


Filler????      It looks like some sandpaper will do the job. Why add weight?


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