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Author Topic: Ercoupe Build (slow)  (Read 2531 times)

Offline Tim Wescott

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Ercoupe Build (slow)
« on: January 14, 2018, 02:40:59 PM »
My ride for the Regionals in May, if I can get it done.  I just got the plans from the printer -- they lack detail.

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Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #1 on: January 21, 2018, 07:58:05 PM »
And ain't I making fast progress?  I'll be lucky to have something flyable -- I think I have too many irons in the fire.

I haven't decided yet whether I'm going to drill holes for my usual stunt jig.  I've chosen to use the original airfoil, so there's not a flat line anywhere to set on a building board.  I'll probably do this on a jig -- it just seems more sane.
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: Ercoupe Build (slow)
« Reply #2 on: January 28, 2018, 05:07:59 PM »
Nineteen ribs cut, at least nineteen more to go.  So far I've been progressing without drawing up plans, but I should maybe at least sketch out the rib layout & which ribs need to be shortened as I go into the wing tips.  Hmm.
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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 wwwarbird

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Re: Ercoupe Build (slow)
« Reply #3 on: January 28, 2018, 08:45:06 PM »

 Just curious, what will the wingspan be?
Narrowly averting disaster since 1964! 

Wayne Willey
Albert Lea, MN U.S.A.
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Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #4 on: January 28, 2018, 08:52:13 PM »
Just curious, what will the wingspan be?

1/8 scale, 60".  I'm trying for not to big, not too small.
AMA 64232

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

Offline wwwarbird

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Re: Ercoupe Build (slow)
« Reply #5 on: January 28, 2018, 09:29:41 PM »

 That's a pretty good sized model, a nice size for scale though. A whole different ballgame, but over the years I've considered doing an Ercoupe stunt model many times. This one will be an interesting build to watch.
Narrowly averting disaster since 1964! 

Wayne Willey
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Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #6 on: February 03, 2018, 05:00:40 PM »
All ribs cut.  I had originally planned on a 2" spacing, but I got to thinking and I decided that 2.5" would be OK (I'm not trying to match the original).  I have the main rib in a CAD program, so I just scaled it down to fit between the LE and TE for the two tip ribs.

20 main ribs
2 mid-tip ribs
2 end-tip ribs

I need to cut holes for lines in the ribs next, then start bending wood for the wingtips.
AMA 64232

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

Offline Fred Cronenwett

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Re: Ercoupe Build (slow)
« Reply #7 on: February 03, 2018, 09:03:09 PM »
That is a great size, big enough you can install a servo and other hardware and not be worried about wing loading. Small models can not tolerate adding the scale details and heavy items such as extra servos.

Another thing that happens with the larger models is that the wing loading per square foot can go up and still fly great. My 96" span B-29 flies with a 39 ounce per square foot wing loading, that same wing loading on a smaller model it would not get the off the ground. the 14 lb overall weight for the B-29 is a pig by stunt standards but flies just like the real B-29 so it's a good model for CL scale.

Math is on your side, if you double the size of the model from 30" to 60" you have doubled the size of the model but the wing area is 400% the area of the smaller model.

30" model would have 142.6 sq inches
60" model would have 570.4 sq inches

You can easily fly the larger model even if the model comes in at 5.5 lbs, but with the smaller 30" model you would be lucky to get airborne if the model came in at 1.25 lbs (or 20 ounces). I tend to round to the nearest 1/4 lb with the scale models instead of quoting model weight to the nearest ounce.

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Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #8 on: February 10, 2018, 06:25:40 PM »
Small progress made on airplane - large progress made on shop.

Sunday or Monday I went into the back shop to find some wood for a tip form, and found that the last of the florescent fixtures had died.  I am sick and tired of florescents, so I've spent my evenings this week installing LED shoplights.  The good news is that it's brighter back there than it has been for years, and I still have the other half of the fixtures to install.  The better news is that it was all overhead work, and my right shoulder hasn't been bugging me for it -- so maybe in 2019 I can get back to flying stunt!

After taking a break from building to fix up my back shop where all the carpentry stuff lives, I ended up making the tip form out of cardboard, in the front shop.  I've got six 22x3/8x1/8 sticks soaking in ammonia water now; tomorrow I'll see if I can bend them.  If I can't hand bend them, I'll heat bend them.  I was going to say "I'll have to figure out how", but as I typed that a solution popped into my head.  Now that I can SEE my welding bench Igrab some pipe and make up a 4" or 6" diameter form that I can hold in my vise and heat up with a propane torch while I'm bending wood over it -- that should be both effective and gonzo, and if I'm careful, perhaps even let me finish the job before I burn down my house.

One of these days I'm going to have to try steam bending balsa.  I've had really, really good success bending wet balsa over a soldering iron for small rubber-powered airplanes.  So balsa seems to be good for heat-bending.  On the other hand, I've seen web sites that say you just cannot steam-bend kiln-dried wood.  I'm not sure if that means that other heat-bending techniques work, or that when you're working with thin sections of wood you can effectively undo the kiln drying by overnight soaking in water.
AMA 64232

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

Offline Will Hinton

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Re: Ercoupe Build (slow)
« Reply #9 on: February 11, 2018, 10:13:39 AM »
Tim, I heat bend kiln dried wood all the time, and hardwood at that when I'm building acoustic guitars.  I've bent maple, rosewood, koa, cherry, mahogany and the like.  I do soak them over night before doing it, but I can't imagine having problems heat bending balsa, even really hard balsa if it's plenty wet.
I feed the torch into one end of an aluminum tube with a baffle an inch from the opposite end to retain as much heat as possible.  I use a four inch and a two inch tubing, depending on the radius of the bend I need.
Just go slow and watch the fingers!  Good luck with it.
John 5:24   www.fcmodelers.com

Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #10 on: February 11, 2018, 02:27:45 PM »
Tim, I heat bend kiln dried wood all the time, and hardwood at that when I'm building acoustic guitars...

Thanks.  It sounds like you do the same as I do -- wet wood over a hot dry thing.  Have you even steam-bent, or does that just not fit into your process?

I'm going to try today with a heat gun, because I don't have any hunks of metal that are a nice 4" radius, other than a cookie tin.  If I get desperate I'll shove the torch into that, but I'm worried about burning up the tin.
AMA 64232

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

Offline John Rist

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Re: Ercoupe Build (slow)
« Reply #11 on: February 11, 2018, 03:09:05 PM »
Balsa wood bends if you soak it in a mixture of household ammonia and water.  I did some molded ringmaster leading edges this way.
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Offline Will Hinton

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Re: Ercoupe Build (slow)
« Reply #12 on: February 11, 2018, 07:50:34 PM »
I would like to have a steam bender, but the way I'm doing it works well enough for me to not spend the extra money on one.  The main thing I have to watch is burning the surface of this expensive exotic wood if I am too slow on my process.  The burns sand out, but at a huge cost of time.
Some of the bending machines available for luthiers are also wonderful machines, but also expensive.  If I were ever to up my output on a steady basis I would likely go that route, but for now; status quo is working well.  I just delivered two new acoustics last week and will start two new acoustic instruments in a couple of weeks.
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Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #13 on: February 11, 2018, 08:43:23 PM »
Balsa wood bends if you soak it in a mixture of household ammonia and water.  I did some molded ringmaster leading edges this way.

You can get it around a much tighter radius with heat.  I've done both.
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: Ercoupe Build (slow)
« Reply #14 on: February 11, 2018, 08:55:20 PM »
You can get it around a much tighter radius with heat.  I've done both.

I need to expand on that:

You can bend a thicker piece of wood around a tighter radius, and when you're done it'll stay there.  If you soak the wood in ammonia water (or plain water for longer, or water with a touch of soap), you can bend a piece around a form tighter than you can dry, and it won't break, and it'll take a bit of a set.  But if you bend it around a hot form you can get it much tighter, and it'll stay.

I've got a Bostonian I call the "Square Coupe" (I have this thing about Ercopes) with tips and tails bent out of 1/16" balsa over a soldering iron: the tail feathers are bent around a 5/16" radius (the radius of a penny, more or less) in places, and while that's as tight as I'd ever want to go with that sized wood, it worked great.  Basically, the vertical stabilizers were bent so that just sitting there they had the right shape on the plan.



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: Ercoupe Build (slow)
« Reply #15 on: February 11, 2018, 09:42:38 PM »
One wingtip bent.  I'll let it cool and dry overnight, or until I get a chance to get down to the shop again.

I ended up using a monocoat gun pointed at a round cookie tin loaded with scrap iron to hold it in place.  You let the wood heat up, it gets flexible, and then you can gently pull it around the form.  If you push it into a bend, or if you get impatient, then it buckles -- which I did, and it did, because I got impatient ("I got impatient and then screwed up" is a running theme in my building, I'm sorry to say).

If I do better tomorrow with the other wingtip, I may go for a 3rd round and see if I can make more pieces with less buckling this time.
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: Ercoupe Build (slow)
« Reply #16 on: February 18, 2018, 05:01:17 PM »
Wingtips bent, sorta kinda acceptably.  (meaning, it's good I'll be using opaque covering).

My cousin is learning guitar building; he bends moistened wood that's wrapped in foil -- I'm gonna try that next time, because I've noticed that the wood seems to bend nicely until it dries out, and then bends no more.

Oh, and wing plans done, such as they are.  Masking tape on the building board and a sharpie marker.
« Last Edit: February 18, 2018, 05:45:14 PM by Tim Wescott »
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: Ercoupe Build (slow)
« Reply #17 on: February 18, 2018, 07:57:54 PM »
Wing taking shape.  It's beginning to look like progress!

Note that the plan is for a very "stunt-ish" wing structure: LE sheeting, capstrips, TE sheeting, with center-section sheeting.  I'm just closing my eyes to what the actual structure of the wing may have been, or whether my particular full-scale example had a fabric- or metal-covered wing (they came both ways, fabric wings have been converted to metal, and sometimes converted back to fabric -- it's very much a question of what your particular example did).  If this were a more precision event, I'd care -- which is exactly why I chose Profile Scale.
AMA 64232

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

Offline Trostle

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Re: Ercoupe Build (slow)
« Reply #18 on: February 19, 2018, 10:05:24 AM »
That's a pretty good sized model, a nice size for scale though. A whole different ballgame, but over the years I've considered doing an Ercoupe stunt model many times. This one will be an interesting build to watch.

Just a comment here on the Ercoupe for semi-scale stunt.  Bob Palmers Mars, Model Airplane News, August 1952, sort of looks like an Ercoupe with it twin verticals, bubble canopy, and tricycle gear.   Cowled in side mounted engine with apple cheeks. (And it is OTS legal.)

Charles Lickliter's Ballerina, Flying Models, October 1959, is another that gives an impression of an Ercoupe with it twin vertical, bubble canopy, but had a conventional gear.   Cowled in inverted engine.  I-Beam construction.

Both of these models were attractive in their own ways particularly if you like twin vertical tails.

Keith



Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #19 on: February 19, 2018, 05:54:36 PM »
LE and bottom half of the TE sheeting in place.  I've agonized about the order of the TE sheeting vs. getting the tip hoop & ribs in place -- I finally realized I was suffering from analysis paralysis, and just got 'er done.  Done and wrong can be fixed.  Never done can't.

TE sheeting is being held up by a 1/2" square stick that's held up by wedges cut to match the angle of the bottoms of the ribs.  The top TE sheeting will be tapered in the back, and will, well, set on top.  If you squint, you'll (maybe) be able to see that I had to block the spar up to make room for the LE to glue on.  I'm going to make all the screwups on this side, so that the inboard side will be perfect.
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: Ercoupe Build (slow)
« Reply #20 on: February 19, 2018, 06:00:38 PM »
I was just reading an Ercoupe pilot's website, and see that there's a scale maneuver unique to the Ercoupe that can best be described as "mush to landing".  Basically, if you fear overshooting the runway, you throttle way back and hold the stick back as far as you can.  The Ercoupe is stall- and spin-proof, so it'll sink pretty fast in a mushing glide.  The trick is to remember that you simply don't have enough airspeed for a flair, so you absolutely need to put the nose down at 200 feet so that you have enough airspeed for landing (and, apparently, to clean the passenger's seat of any residue if you're flying with a non-Ercoupe pilot who you failed to warn).  1/6 scale 200 feet is 33 feet -- so, probably not a maneuver for CL scale.

Note that I've never flown a scale Ercoupe -- but I've had RC planes with similar stall characteristics, and by golly I've done similar things trying to get them to spin.  It does work, sorta.
AMA 64232

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

Offline wwwarbird

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Re: Ercoupe Build (slow)
« Reply #21 on: February 19, 2018, 06:28:31 PM »
Just a comment here on the Ercoupe for semi-scale stunt.  Bob Palmers Mars, Model Airplane News, August 1952, sort of looks like an Ercoupe with it twin verticals, bubble canopy, and tricycle gear.   Cowled in side mounted engine with apple cheeks. (And it is OTS legal.)

 Thanks Keith, yeah, I've eyeballed the Mars before thinking the same thing, it could easily be bashed into an Ercoupe.
Narrowly averting disaster since 1964! 

Wayne Willey
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Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #22 on: March 29, 2018, 12:38:08 PM »
I got to the point of getting that nice heat-bent wingtip installed and stalled for a while.  The upside of just starting to build is that you don't have to figure it all out ahead of time.  The downside is that you're constantly painting yourself into corners.

At any rate, here it is mocked up, showing slight progress.
AMA 64232

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

Online Avaiojet

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Re: Ercoupe Build (slow)
« Reply #23 on: March 29, 2018, 12:49:25 PM »
I got to the point of getting that nice heat-bent wingtip installed and stalled for a while.  The upside of just starting to build is that you don't have to figure it all out ahead of time.  The downside is that you're constantly painting yourself into corners.

At any rate, here it is mocked up, showing slight progress.

Really really nice.  H^^

I looked on line. Lots of color choices.

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Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #24 on: March 29, 2018, 02:04:10 PM »
I looked on line. Lots of color choices.

It was a popular plane.  I have a walk-around set of photos, for a plane that's basic red and white.  I'm probably going to use whatever red and white comes out of Rustoleum canss, and take my lumps for not trying to match things exactly.
AMA 64232

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

Offline wwwarbird

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Re: Ercoupe Build (slow)
« Reply #25 on: April 04, 2018, 08:53:01 PM »

 May is right around the corner.   S?P ;D
Narrowly averting disaster since 1964! 

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Re: Ercoupe Build (slow)
« Reply #26 on: May 19, 2018, 10:37:25 PM »

 How's the 'Coupe coming?

Narrowly averting disaster since 1964! 

Wayne Willey
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Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #27 on: May 20, 2018, 08:00:47 AM »
How's the 'Coupe coming?

Between Work, Life, and a design-as-you-go approach, I got stalled.  If I make the Regionals with the plane, it won't be 2018!  The big demotivator was getting my shoulder in shape for flying stunt, which suddenly meant that the Call of the Wild has me out flying.

I got stuck on making the wingtip look good and not be a construction nightmare.  As part of this, the actual bent-wood tip hoop went on with about a 1/8" gap between the end of the spar and the hoop, which stalled me.  I finally broke down and extended the spar, even though the result looks like the joinery that you'll never see in a 150-year-old barn, because the ones done that badly have all fallen down.  Once I managed to go ahead and make the joint, though, I could get work done and the wing is ready for LE sheeting.
AMA 64232

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

Offline wwwarbird

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Re: Ercoupe Build (slow)
« Reply #28 on: May 20, 2018, 09:11:32 PM »

 Hmm, looks like adding those diagonals would have been a good idea anyway. Heck, add them to the other tip too and it'll look like you knew what you were doing the whole time.  ;D
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Wayne Willey
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Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #29 on: June 02, 2018, 06:10:42 PM »
Oh, it's a good thing I'm chronicling this -- I just looked at the picture I'm posting and realized two things.  First, that I left out the holes for the leadouts.  I was planning on making holes "later" -- later came, and I was still forgetting.  This is really later -- fortunately I haven't glued anything down yet.  Second, I almost built two left wings, because I built the other wing upside down over the plans, and just started this one rightside up.  So -- off to drill holes and fit spar notches on the topside of the wing.

Oh -- and I'm making progress.  Two 1/4" square sticks stripped from my stock of 11-pound balsa (because it's for spars, and I'm trying to use up the heavy wood).
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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: Ercoupe Build (slow)
« Reply #30 on: June 02, 2018, 06:26:01 PM »
And I need to make a @#$% bellcrank.  Or finally rip apart my Nobler, which will never fly again.  But I think I'll make one.
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: Ercoupe Build (slow)
« Reply #31 on: June 02, 2018, 07:23:37 PM »
For stunt, I've been making my own bellcranks from 1/8" phenolic.  I see no reason not to here, because I'm just doing a bog standard 2-wire setup and using a radio for throttle control.  I've been making nifty bellcrank bearings from aluminum on my lathe, holding them on with nuts scavenged from potentiometers.  Just now, I realized that a potentiometer is a nifty bellcrank bearing, you just need to do some disassembly to get to the good part.

I'm not sure if the thing is zinc or aluminum -- I'd hesitate to use it for stunt without a lot of thought (and possibly testing), but I don't see this airplane getting hundreds of flights a year, so it's probably OK.  The actual bearing is the part at about 2 1/4 inches on the ruler.
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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: Ercoupe Build (slow)
« Reply #32 on: June 03, 2018, 11:15:56 PM »
Right wing starting to be framed up (with leadout holes, thank goodness!).  You can see the left wing in the background with clothspins all over the inboard rib -- that's because I've been building straight wings for so long, I forgot that you want to angle the top of the inboard rib inward to accommodate it.  D'oh (or T'oh if you want to be classy and say it in French...)  So I glued another rib onto the first, and will sand things to the correct angle.

Second picture is the bellcrank, bearing courtesy of Alps electronics.  Before you ask -- yes, it'll be a floating bellcrank.  I'm pretty sure I'm going to mount it between the first two ribs of the right wing, so that the leadout position will be nice, and so that I don't have to hassle with getting the bellcrank to work correctly around the dihedral joint.  But I may change my mind -- the downside of engineering as you go is that you paint yourself into corners.  The upside is, there's no plans to disagree with when you decide to make changes.
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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 John Rist

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Re: Ercoupe Build (slow)
« Reply #33 on: June 06, 2018, 09:42:35 PM »
Love the work bench.  Looks like mine!   LL~
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Re: Ercoupe Build (slow)
« Reply #34 on: June 08, 2018, 10:24:01 AM »
Snuck in to my shop on the way to work.  Got the second wing LE installed.  Note the super high-tech clamping system.  The older I get, the less prone I am to using commercial clamping products -- weights, cloths pins, rubber bands, ACE bandages -- they all seem to do well in their place.  I do have some small C-clamps and those giant hand-clamps, because they work.
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Online john e. holliday

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Re: Ercoupe Build (slow)
« Reply #35 on: June 11, 2018, 09:42:42 AM »
Yes, I have used that type clamp as well as masking tape. D>K
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Offline Tim Wescott

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Re: Ercoupe Build (slow)
« Reply #36 on: June 16, 2018, 12:59:34 PM »
More progress -- the left tip hoop is installed, now I need to make the ribs & put them in (yes, in that order -- this is a consequence of just tossing it together instead of designing it first -- the ribs will be sorta copied from the R side, and sorta just cobbled together.  I also need to figure out the leadouts).

Note that there are FOUR splices on this thing -- there needs to be a scarf splice on the bottom spar so that it can break up to match the slope of the tip -- that part's hunky-dory.  But I didn't need to put the pre-cut piece on TOP, requiring a splice, I didn't need to put the bottom sheeting on BACKWARDS (there's a nice pointy end on the inboard side, where it'll get whacked off), and I didn't need to get all cheap and splice the little bit of bottom spar in the middle.

At some point in any project I just declare the thing a concatenation of errors and keep driving forward.  This one is happening a bit early, but it was going to happen sooner or later.
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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: Ercoupe Build (slow)
« Reply #37 on: June 25, 2018, 10:26:10 PM »
Starting in on the LE sheeting.  I never like the way it worked the last time, and find some new way to make myself almost happy.  This time I'm gluing the LE of the LE sheeting to the LE (that's easy to scan!), waiting for the glue to cure, then gluing down the rest, possibly after wetting the top.

CA on the joint shown, Tite-bond on the rest.
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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: Ercoupe Build (slow)
« Reply #38 on: June 30, 2018, 09:20:29 PM »
Went to put in the LE bottom sheeting and realized that it would go a lot better if I put the control system in first.  So, one control system.  The leadout guide is 1/32" aluminum, so it may be a bit wimpy -- but it's also replaceable.  It'll go on a 1/16" thick plywood plate, surrounded by 1/32" balsa so that I can finish things off nicely.  I'm going to need some sort of an internal guide at the last rib, to keep them from rubbing on balsa, but I think I can just use a section of big brass tube.
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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: Ercoupe Build (slow)
« Reply #39 on: July 02, 2018, 04:42:12 PM »
Bottom LE sheeting on the inboard wing -- woo hoo!  Plus the leadout guide mounting plate.  I screwed up and made it 3/16" too short -- it fits from rib to rib instead of overlapping to match the cap strips.  So I needed a bit of extra wood.  I'll sand it down to match the mounting plate.
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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: Ercoupe Build (slow)
« Reply #40 on: July 03, 2018, 06:44:19 PM »
I think I'm in love.  I always have trouble with getting the glue joints right on leading edge sheeting.  And I chose to use a scale airfoil on the Ercoupe, complete with a mild 'S' curve in the bottom of the wing that makes the bottom LE sheeting concave.

I'm using Gorilla Glue this time around, and boy am I happy so far.  It's easy to apply with a disposable glue bulb, I know from experience that it sticks well, and because it foams up you don't need much and it fills the inevitable gaps between the ribs and the sheeting -- so even though my joints still aren't perfect, they're at least full of glue and are still reasonably strong.
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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.

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Re: Ercoupe Build (slow)
« Reply #41 on: July 10, 2018, 09:12:02 PM »
All capstrips on, and this finishes off the sheeting on the outboard wing.  I need to sheet the inboard wing center section, and it'll be ready for joining.  Then I can make the fuselage and tail surfaces, which ought to go quick.

Sharp-eyed real scale people will note that I made no attempt to match the Ercoupe structure -- I just made a conventional model wing to the Ercoupe outline.  I'm not sure how much that'll have an effect for profile scale -- it would be interesting to know.
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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.

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Re: Ercoupe Build (slow)
« Reply #42 on: July 12, 2018, 06:52:43 PM »
Wings mocked up for dihedral.  Not yet glued -- I should fix that.  As yet another consequence of a process that goes conceive - build - design, the wings are definitely a bit different from side to side -- sort of like those "identify the differences between these pictures" puzzles.
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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.

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Re: Ercoupe Build (slow)
« Reply #43 on: July 12, 2018, 07:08:54 PM »

 There's a wing in that picture?  Oh wait, I think I see it now...  :##
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Re: Ercoupe Build (slow)
« Reply #44 on: July 12, 2018, 09:11:26 PM »
And no one pointed out that I'd left off the landing gear blocks.  Fortunately I figured it out before I glued the halves together; unfortunately the cap strips are in place.  So a delay is happening while I get the LG into the wing.
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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.

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Re: Ercoupe Build (slow)
« Reply #45 on: July 13, 2018, 10:33:08 AM »
OK.  Not as bad as it could be, although I'll still need to make the block supports from the inside out.
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Re: Ercoupe Build (slow)
« Reply #46 on: July 13, 2018, 10:33:43 AM »
Another oops?  Wait til you start sanding fuse on built up fuse to discover you left out the tail wheel gear. HB~>
I was always taught to respect my elders, but it keeps getting harder to find one.
Today I broke my personal record for most consecutive days lived.
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Re: Ercoupe Build (slow)
« Reply #47 on: July 13, 2018, 10:36:30 AM »
If I start sanding on this fuse and discover that I remembered the tail wheel I'll know I'm in trouble.
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Re: Ercoupe Build (slow)
« Reply #48 on: July 13, 2018, 11:11:46 PM »
Ercoupe tail wheel? All the ones I worked on had nose wheels.
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Re: Ercoupe Build (slow)
« Reply #49 on: July 14, 2018, 08:07:53 AM »
Ercoupe tail wheel? All the ones I worked on had nose wheels.

I flew one that had a nose wheel. Almost bought it.

It was an oldie back then, the 70's. Had no rudder pedals.  n~

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