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Estes Shuttle - bending balsa

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SecondRow

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So, I’m currently building the Estes Shuttle. After seeing someone else’s work on FB, I’ve been inspired to replace the cardstock top and bottom of the shuttle body with balsa. It looked really nice. I also found an old post from John Boren (the kit’s designer) suggesting 1/32” balsa. I figured, WTH, I’ll give it a try. The worst that could happen is I have to sand off the balsa and use the cardstock.

Here are the kit patterns and the balsa cutouts I made from them. The pattern was a little bit wider at the base than the balsa I had, so I couldn’t make one piece per side. I had to split each one up. E483430D-1442-4011-8989-FEC8A453115B.jpegAB4509BA-69A8-44AD-B5A2-8C7A01B11C5B.jpeg
 

SecondRow

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Next, I checked how much the paper and the balsa weighed Not gonna bother if the balsa weighs more. This is a glider, it’s gotta fly! No worries, though. The balsa weighs 3 grams less. 90649CEA-72C8-4189-8150-9437C36A931C.jpeg4D6D408D-3552-443A-AC82-21A95A1D8571.jpegJust to see if it was really going to make a difference, I weighed the glider frame I had already built. It still needs the nose and fins, but the 3 grams should make a significant impact.68FA8C3B-0E1C-4DF0-BC0A-F9266C639AE2.jpeg
 

SecondRow

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Now I needed to figure out how to bend balsa. Luckily, there was a couple threads about that recently. The technique that I keep reading about is using Windex (any ammonia/water mix will probably work just as well, but Windex is what I had on hand). I don’t have any pictures of the process, but it turned out really well. I saturated the balsa with Windex on both side, laid it on the glider frame and wrapped an Ace bandage around it overnight. After the wood dried, I unwrapped it and the balsa was curved to the contour of the glider. +1 for the Windex technique. I did it for the other balsa parts, glued them all up, sanded to shape and voila!B3F37EDA-8A32-4F57-A818-19568B2AAC19.jpeg36DD0D63-DC65-469C-A7AA-D6B211910CC8.jpeg69257C06-0DA2-4B4E-A30F-46AD1707648A.jpeg
I think it looks pretty good. Now I’ve just got to finish it up and see if it flies.
 

neil_w

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Nice work. 1/32" balsa is really compliant and pleasurable to work with. Does it come out lighter than with the cardstock?
 

SecondRow

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Yes. The cardstock parts weighed 9 grams. The balsa weighed 6 grams. I haven’t finished the glider yet, but the frame plus balsa parts is 17 grams. I still need to put on the the fins and nose cone. It’s a 3 gram difference over what I think will end up being around 30 grams with paint and balancing clay (no idea for sure, it’s just a SWAG).

The balsa is easy to work with for sure - in one direction. When I bent it along the grain, it went easy. I could curve the wood to lay across the glider with no problem. Across the grain, not so much. You’ll see for the top part, the glider had to be bent across the grain (from about halfway to the nose). Not having done this before, I was afraid it was gonna snap without some kind of treatment. Spraying with Windex made it pliable. Very easy to work with.
 

mo2872

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Nice work! (And you get bonus points for spelling "voila!" correctly)
 

jrap330

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Now I needed to figure out how to bend balsa. Luckily, there was a couple threads about that recently. The technique that I keep reading about is using Windex (any ammonia/water mix will probably work just as well, but Windex is what I had on hand). I don’t have any pictures of the process, but it turned out really well. I saturated the balsa with Windex on both side, laid it on the glider frame and wrapped an Ace bandage around it overnight. After the wood dried, I unwrapped it and the balsa was curved to the contour of the glider. +1 for the Windex technique. I did it for the other balsa parts, glued them all up, sanded to shape and voila!View attachment 427916View attachment 427917View attachment 427918
I think it looks pretty good. Now I’ve just got to finish it up and see if it flies.
You needed staples to attached both half's or is that prior to gluing to frame? Once completed do you dare harden with CA since it is bent with the grain?
 

SecondRow

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I’m not sure what you mean by staples. I didn’t staple anything. I think maybe you’re referring to the precut slots on the glider frame that the fins will attach to?

I won’t be using CA to harden it. Just light coats of primer and paint to finish.
 

jrap330

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I’m not sure what you mean by staples. I didn’t staple anything. I think maybe you’re referring to the precut slots on the glider frame that the fins will attach to?

I won’t be using CA to harden it. Just light coats of primer and paint to finish.
That is probably it..the slots...from picture looks like Electrical wiring staples.
 

SecondRow

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I finally got around to finishing the shuttle. I had a devil of a time getting it trimmed. Still haven’t launched it. Final weight of the shuttle ending up being 48g. So, using the balsa over the cardstock saved about 6% on weight. I tried to go light with paint. You can still see some wood grain. But I think better modelers than me could do much better on weight savings. All in all, this was a fun little project and I learned a new skill. So I’m good. Hopefully, it’s first flight will be unremarkable.
8BC6C168-8036-4218-A57F-7C9AD47D284D.jpeg
E9A21860-2423-4DAB-AE47-0AC00173C13B.jpeg
image.jpg
 

mbeels

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Yeah, that came out great! It certainly looks better with the balsa, and I bet it will fly better as well.
 

samb

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Triple "LIKE" ! Looking forward to the flight report. In my fantasy build of this one I substitute dope and tissue for the cardstock. I really need to pull the trigger ...
 
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