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Old Jan 10, 2013, 12:08 PM
Experienced Balsa Mangler
United States, AL, Tillmans Corner
Joined Oct 2012
600 Posts
Day 10 -- Stabilizer

Got the two large spars cut and glued into the frame. I'm assembling the whole thing as one piece, then I'll cut the elevator halves out after everything cooks.
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Old Jan 10, 2013, 12:27 PM
I like real wooden aeroplanes!
Sundancer's Avatar
South-west France
Joined Sep 2007
4,426 Posts
Quote:
Originally Posted by cpmcgraw View Post
Day 10 -- Stabilizer

The parts are starting to come together now, and it's beginning to look like an airplane. I've dry-fitted the loose balsa into the pattern to see if the cut-outs were OK, and as Photo 1 shows, it's a pretty sight!
Looking nice cp. I'll with you in limiting the use of CA to "convenience" bits where it can be very useful, but for proper building I wouldn't want to use anything other than a good aliphatic resin. Oh, except for one special case; where there is a need to join 1/16" balsa sheets edge to edge for wing skins, nothing beats balsa cement! Hinge the sheets together with masking tape, pre-cement the edges and let it dry then apply a second coat and hinge the sheets flat, pinning down on polythene. When dry the joint can be sanded to perfection.
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Old Jan 10, 2013, 03:54 PM
Edubarca
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Colombia, South America
Joined Oct 2009
1,064 Posts
Quote:
Originally Posted by cpmcgraw View Post
Here in Mobile, Alabama, the Hobby Lobby chain store sells a single 1/16" x 4" x 36" sheet for (US) $4. I can at least say the Hobbytown USA store is more reasonably priced...

I have a larger project in the wings, a KK Falcon, which I'll be posting shots of one day, and I'll be needing a lot more balsa for it. I'm just holding off on that order as long as I can...
You might or might no believe me but 1/16 x 4 x 36 (1.5mm x 10cms x 92cms.) is locally availably (retail) for just USD1.50!!!!! Balsa grows in our country, labour is cheap and there are four balsa processing companies in our country. For my kit production I'm buying perhaps the best balsa available which is exported worldwide from a company called Balco Ltd. in the city of Bucaramanga. Perhaps the balsa you are purchasing is Colombian!!! And I insist: Your Envoy is coming very nice indeed.
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Old Jan 10, 2013, 03:55 PM
Registered User
Canada, ON, Hamilton
Joined Oct 2005
2,451 Posts
Looking good CP. I too don’t use very much CA glue. I like the Weldbond
http://www.weldbond.com/application_uses
and buy it by the gallon and pour it into smaller bottles. I guess I use more glue than is really necessary as I make a small fillet around each glue joint. Being water based, it doesn’t weigh too much when it dries. I’ve never had a glue joint break with Weldbond. I’ve had many “cracked glue joints” when using CA.
John
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Old Jan 10, 2013, 03:59 PM
Edubarca
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Colombia, South America
Joined Oct 2009
1,064 Posts
Quote:
Originally Posted by Sundancer View Post
Looking nice cp. I'll with you in limiting the use of CA to "convenience" bits where it can be very useful, but for proper building I wouldn't want to use anything other than a good aliphatic resin. Oh, except for one special case; where there is a need to join 1/16" balsa sheets edge to edge for wing skins, nothing beats balsa cement! Hinge the sheets together with masking tape, pre-cement the edges and let it dry then apply a second coat and hinge the sheets flat, pinning down on polythene. When dry the joint can be sanded to perfection.
My models, including the Sky Skooter are all built 99% with medium viscosity CA from Palm Labs. Only the engine bearers, dihedral joiners and firewalls are glued with 6 minute epoxy. Sometimes I use Elmer's glue all when I'm not in a hurry. Titebond is not available here, as far as I know. The models I have built ever since Hot Stuff came out in the late seventies, have never had a glue joint failure. Believe me!!!!!
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Old Jan 10, 2013, 04:54 PM
Experienced Balsa Mangler
United States, AL, Tillmans Corner
Joined Oct 2012
600 Posts
Quote:
Originally Posted by Edubarca
You might or might no believe me but 1/16 x 4 x 36 (1.5mm x 10cms x 92cms.) is locally availably (retail) for just USD1.50!!!!! Balsa grows in our country, labour is cheap and there are four balsa processing companies in our country. For my kit production I'm buying perhaps the best balsa available which is exported worldwide from a company called Balco Ltd. in the city of Bucaramanga. Perhaps the balsa you are purchasing is Colombian!!! And I insist: Your Envoy is coming very nice indeed.
Oh, yes, I believe it!

I just checked Balsa USA, and they list that sheet at $1.82, which is reasonable. My previous supplier of balsa, Lone Star Balsa in Texas, lists that sheet at $1.14 for the "AAA grade", and $2.34 for the 4-6 lb (light, or select grade) sheets. Problem with Lone Star, they say they're completely out of stock on everything 4" wide...

My LHS sells Bud Nosen balsa, and the prices are high(er).

SIG sells it for $1.74 mail-order, and that may be where I place my next order. SIG used to be the best; it's been such a long time since I've seen their balsa here in Mobile, though. I don't know if they've kept up with the quality...
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Old Jan 10, 2013, 04:57 PM
Experienced Balsa Mangler
United States, AL, Tillmans Corner
Joined Oct 2012
600 Posts
Quote:
Originally Posted by Edubarca
Titebond is not available here, as far as I know.
Do you have anything like a Home Depot in your area? They're plentiful here, popping up almost like balsa trees...

Titebond, in all its variations, is primarily a construction advesive and can be found in most DIY shops (home fix-up).
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Old Jan 10, 2013, 05:01 PM
Experienced Balsa Mangler
United States, AL, Tillmans Corner
Joined Oct 2012
600 Posts
Quote:
Originally Posted by JohnAV8R
I like the Weldbond
http://www.weldbond.com/application_uses
and buy it by the gallon and pour it into smaller bottles.
Last time I bought a large container of Titebond, it went bad before I could use half of it. I just picked up a 16oz bottle a couple weeks ago. I'll probably have at least half the bottle by this time next year...

Unless I start building a bunch of Ben Shereshaw's designs...
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Old Jan 10, 2013, 08:41 PM
Experienced Balsa Mangler
United States, AL, Tillmans Corner
Joined Oct 2012
600 Posts
Day 10 -- Wing

This is a milestone point in the build. I had to dry-fit some of the wing pieces together to see how they would look. Sweet! I've still got the tips and the dihedral braces to cut, so the glue-up might not be for a couple of days.
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Old Jan 11, 2013, 07:14 AM
So I'M meant to be in control?
Colonel Blink's Avatar
Ilkley, West Yorkshire, UK
Joined Nov 2008
3,469 Posts
I owe you some thanks, Craig.... I have been drawing up some fuselage formers in Paint for my Britplan build. Has lots of advantages over pencil and ruler! I would never have done it if I hadn't read about you drawing everything in GIMP and Inkscape.

My first step towards CAD!!
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Old Jan 11, 2013, 12:33 PM
Experienced Balsa Mangler
United States, AL, Tillmans Corner
Joined Oct 2012
600 Posts
Quote:
Originally Posted by Colonel Blink View Post
I owe you some thanks, Craig.... I have been drawing up some fuselage formers in Paint for my Britplan build. Has lots of advantages over pencil and ruler! I would never have done it if I hadn't read about you drawing everything in GIMP and Inkscape.

My first step towards CAD!!
More than welcome, Colonel. Glad to hear it works!
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Old Jan 11, 2013, 06:25 PM
Experienced Balsa Mangler
United States, AL, Tillmans Corner
Joined Oct 2012
600 Posts
Day 11 -- Wing

More of the dry-fitting activity. Tips are 1/8" balsa, LE and TE are cut from 3/16" sheet. There is an error on the plans showing the LE as a 3/4" thick piece. The TE is 3/16" x 3/4", and the LE should be 3/16" x 5/16". Photo 1 shows everything except the dihedral brace and the gussets.
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Old Jan 12, 2013, 12:48 PM
Experienced Balsa Mangler
United States, AL, Tillmans Corner
Joined Oct 2012
600 Posts
Day 12 - Wing

This is one of the most tedious steps of this build -- cutting the dihedral braces. I don't have access to a scroll saw or a disk sander right now, so I have to use what I have on hand. This was done with only an x-acto knife, a steel straight-edge, and a small sanding block. The plywood is three-layer birch AC grade (not lite-ply!), 1/16" thick.

The way I got to this point was to take the plan and start with the original brace pattern. Knowing that I might want to "pull some Gs" occasionally, I figured I might better increase the surface contact area on that lower spar. These braces extend past the W2 rib to touch the inside of W3. Along the top of the brace, I raised the upper edge between W1 and W2, with the angle (9 degrees per panel) cut into the W1 edge. This allows me to add a "filler" to the tops of the lower spar between W1 and W2.

Once I got the pattern, I printed it out onto sticky-back label paper, then applied the label to the plywood. The upper brace in Photo 1 shows how it looks before it gets cut completely (bottom edge of the brace has already been trimmed away). Using the steel edge to guide the blade, I just make repeated cuts until I hear the plywood "crack", when the knife starts cutting through the third layer. Then I "bend" the crack with finger pressure, and finish the cut with the knife. I sand the rough splinters away with the small sanding block.
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Old Jan 12, 2013, 12:57 PM
I like real wooden aeroplanes!
Sundancer's Avatar
South-west France
Joined Sep 2007
4,426 Posts
Cutting ply without a scroll saw is like banging your head against a brick wall - nice when you stop! Still, it's done now and it looks fine!
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Old Jan 12, 2013, 01:34 PM
Experienced Balsa Mangler
United States, AL, Tillmans Corner
Joined Oct 2012
600 Posts
Day 12 -- Wing

Photo 1 shows the two dihedral braces dry-fit into the right wing panel. I got the other pieces glued into place this morning, and should be assembling the left panel this afternoon. In the photo, notice how the braces snug up against the W2 rib. There will be a filler on the top of the spar between the braces, and then I will add some gussets to the inside corners to help distribute the stress loads.

Quote:
Originally Posted by Sundancer
"Cutting ply without a scroll saw is like banging your head against a brick wall - nice when you stop!"
AMEN to that! It's a real wrist-breaker for one, aside from the constant fear of slipping with the blade...
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