Best method to bend balsa

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Top pic is definitely not C; if it's not A then it is B. I have a piece of C-grain and it is quite distinct.

They are sufficiently bendy that I can't tell the difference. :) I'll be making 3.25" diameter rings with them at some point, we'll see how that goes.
 
Again going back to post 124, @rcktman prefers 1/64 PLYWOOD over BALSA?

I would think the plywood would also be stronger. Seems like 1/64” balsa would crush like paper, but would weigh next to nothing,
 
Again going back to post 124, @rcktman prefers 1/64 PLYWOOD over BALSA?

I would think the plywood would also be stronger. Seems like 1/64” balsa would crush like paper, but would weigh next to nothing,
For the Ringhawk build 1/64" ply was easier to form into a ring and much stronger than 1/16" balsa. I'd never use 1/64" balsa -- too fragile in this instance.
 
I thought that A, B, or C balsa only really made a difference bending across the grain. But if you're bending along the length of the grain, I don't think A, B, or C makes a terribly big difference. The density of the balsa probably makes a bigger difference. I'd just do the hand test and see which one wraps around your direction easier.
 
I thought that A, B, or C balsa only really made a difference bending across the grain. But if you're bending along the length of the grain, I don't think A, B, or C makes a terribly big difference. The density of the balsa probably makes a bigger difference. I'd just do the hand test and see which one wraps around your direction easier.
Density relates to balsa strength, A, B, or C relates to flexibility, so it will definitely affect bending along the grain. If it's difficult to tell if the sheet is A, B, or C, then by all means try each to see which one bends easiest.
 
@rcktman and @neil_w , how does 1/32” balsa hold up?
Not well at all if you only have one sheet of it. I will be laminating two or three layers, which will be plenty strong.

I've used the 1/32" balsa for the body bands on the IRIS-T, and the skin on the Skywriter (that's why I have some on hand right now). It's very good for skinning in general because it's so flexible, light, and easy to work with. I suspect it gets used most in balsa airplanes (the serious stuff, in addition to the little plastic package Guillow planes).
 
@rcktman and @neil_w , how does 1/32” balsa hold up? Still seems like it would be fragile.
I used 1/32" balsa for a recent build. When I tried to pick up a rudder I made from it from my workbench it snapped like a potato chip. Make life easier and stick with 1/16" balsa or 1/64" ply. :)
 
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I will be laminating two or three layers, which will be plenty strong.
I frequently have done FLAT balsa laminations. I do at least one sheet with grain 90 degrees to other sheet(s)

@neil_w When you due bent balsa laminations, do you alternate grain directions?

Eric (@Rktman ), how strong is the 1/64 plywood? Seems like if the plywood is that strong, and already laminated, makes sense to start that way.

A bit pricey, $32 for a 12x24 inch sheet, but may be worth it for time saved.

https://www.amazon.com/Midwest-Prod...id=1607435454&sprefix=1/64+ply,aps,186&sr=8-4
Oops, post 153, you said it was stronger than 1/16” balsa
 
I frequently have done FLAT balsa laminations. I do at least one sheet with grain 90 degrees to other sheet(s)

@neil_w When you due bent balsa laminations, do you alternate grain directions?

Eric (@Rktman ), how strong is the 1/64 plywood? Seems like if the plywood is that strong, and already laminated, makes sense to start that way.

A bit pricey, $32 for a 12x24 inch sheet, but may be worth it for time saved.

https://www.amazon.com/Midwest-Prod...id=1607435454&sprefix=1/64+ply,aps,186&sr=8-4
Oops, post 153, you said it was stronger than 1/16” balsa
@BABAR I'm not sure where you live but if you have a Menards in your area they carry both 1/64" & 1/32" Birch plywood in 12" x 24" sheets. The 1/64" is $17.09.

https://www.menards.com/main/doors-...craft-plywood-panels/5240/p-1444439592917.htm
 
@neil_w When you due bent balsa laminations, do you alternate grain directions?
Not for a ring, where strength perpendicular to the grain is pretty much irrelevant. The main reason for laminating is that bending a thicker piece of balsa to the desired radius would be impractical without a heavier dose of ammonia than I care to employ. The lamination process itself adds a bit of strength, but that's merely a useful side effect.
 
I've used the 1/32" balsa for the body bands on the IRIS-T, and the skin on the Skywriter (that's why I have some on hand right now). It's very good for skinning in general because it's so flexible, light, and easy to work with. I suspect it gets used most in balsa airplanes (the serious stuff, in addition to the little plastic package Guillow planes).
+10 on that, it's absolutely great for skinning and small structures! Not so great for fins or glider wings (don't ask me how I know 😬).
 
Not for a ring, where strength perpendicular to the grain is pretty much irrelevant. The main reason for laminating is that bending a thicker piece of balsa to the desired radius would be impractical without a heavier dose of ammonia than I care to employ. The lamination process itself adds a bit of strength, but that's merely a useful side effect.
Okay. I had figured the main advantage was the change in grain direction.
 
I forgot to mention that not only does Menards have the craft plywood but they also carry 4" x 24" sheets of balsa and basswood. Plus bags of various pieces of balsa blocks. I made my RingHawk nosecone out of one of the 2x2x3 inch blocks.

You'll find this stuff in the building supplies area kind of near their thick plywood. I couldn't find it (although I've walked past it dozens of times in the past without noticing it) so I asked a clerk. He had no idea what I was talking about so he asked another clerk who knew exactly what I was talking about & where it was.
 
I forgot to mention that not only does Menards have the craft plywood but they also carry 4" x 24" sheets of balsa and basswood. Plus bags of various pieces of balsa blocks. I made my RingHawk nosecone out of one of the 2x2x3 inch blocks.

You'll find this stuff in the building supplies area kind of near their thick plywood. I couldn't find it (although I've walked past it dozens of times in the past without noticing it) so I asked a clerk. He had no idea what I was talking about so he asked another clerk who knew exactly what I was talking about & where it was.
Thanks, it keeps getting better and better! I used to get all my balsa locally from A.C. Moore, but they got bought out by Michaels, which decided not to carry any balsa. Hobby Lobby here has a limited supply and what's available is usually warped or broken sheets, so I'm especially glad to find another source, even if it's online.
 
Thanks, it keeps getting better and better! I used to get all my balsa locally from A.C. Moore, but they got bought out by Michaels, which decided not to carry any balsa. Hobby Lobby here has a limited supply and what's available is usually warped or broken sheets, so I'm especially glad to find another source, even if it's online.
@Rktman is you do a search for balsa a then for basswood on their website you'll see what they carry. Glad to help!
 
@Greg Furtman @neil_w @Rktman @BABAR @mbeels

So you want to make rings? Please see images. I made 2 that are 17" in diameter. 2 layers of 1/16" Basswood sandwiched around 1 layer of 1/8" Balsa. I have 2 rings made for a futuristic rocket I am currently finalizing. They are 3" width material. See the bundle of left over and back-up pieces. I experimented how long I could make the pieces to reduce time making the ring. I had to cut the Basswood lengths down to 24” and the Balsa to 9” to reduce failing when pressed into shape. I used Windex to soak the wood. The circumference was approximately 56”.

I bought the largest cake ring I could find for my design ideas and used 4” steel edging cut to length as an initial compression tool. Once the wood was placed in the cake ring I used the edging and clamps to hold the wood in place. I sprayed a bit more Windex in between the compression to further soak the wood just after clamping. I let it set overnight. The next day I transferred the part(s) to an adjustable (and smaller) cake ring to tighten the cord length. This second ring made it easier to decrease the cord lengths. This made it easier when I glued the sections together I did not have to fight rebound in the wood as much.

I built up the rings bit by bit gluing compressing, gluing & compressing. The final cords I re-cut (after they were bent of course) to fit. They were a snug fit for the last sections and required some planning to determine the order of what parts go in next. I repeated the steps for the inner Basswood layer.

Steam method is not the way to go in my opinion. I used a steamer repeatedly in the beginning. The Windex l breaks the lignin better and it’s easier to work with. If you all have questions I’ll glad to answer or need more images as reference please let me know.
 

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Nice job looks great. That must be one heck of a big rocket!
The bigger the ri g is, the easier it is to bend the balsa sheet without breaking it. The wood doesn't have to bend as tightly as with a 5" ring. When the size gets down to something that small, something else like thin ply as suggested earlier would be easier to bend and stronger than balsa.
 
Nice job looks great. That must be one heck of a big rocket!
The bigger the ri g is, the easier it is to bend the balsa sheet without breaking it. The wood doesn't have to bend as tightly as with a 5" ring. When the size gets down to something that small, something else like thin ply as suggested earlier would be easier to bend and stronger than balsa.

I can only recommend thin layers laminated in this case, Cut the lengths short and then bend into shape.

The Rocket I'm working on is 65" with a mix of 3D printed parts from Carl Campbell, Estes and Semroc components. 29 MM mount.
 
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