Balsa sheeting advice

[heinkel]

Looking for some advice on sheeting the fuselage of my CAP Stuka.Should i cut the sheet into narrow strips or soak the sheet , dosn't look like it will bend as it tends to break , cheers.

[Rob Lewis]

I would soak it myself. Works a treat. Recently lined some wheel wells by soaking and didn't have any problems with breaks.

 

Cutting it into narrow strips would mean having to get precise angles on the edge of every strip, so theres no gaps when you sand smooth.

[Erfolg]

Totally agree with Rob.

 

I personally just go a little further, I bend over either the model, or some other item, hold in place with elastic bands and leave to dry.

 

Where the contours are particularly demanding, after bending two adjacent sheets, I place them on the model and cut through both whilst in situ, done with care the joints are perfect.

[andy watson]

Soaking with ammonia will make it even more flexible than just water.

[Erfolg]

At a personal level, I worry about using any chemicals. I find that it is all to easy to damage clothing or household furniture by splashes etc. If the chemical can stain, I know, however careful I am, I will damage something, for me it is inevitable.

 

I have found that I can bend both plywood and balsa, to a diameter as small as 25mm.

 

Is it as flexible as ammonia, possibly not, yet done with just a little care not difficult.

 

In the past, for long small sections, I have made a steam heating tube, simply attaching a flexible tube onto a stiff tube, which holds the pieces to be bent, the other end of the flexible attached to a non automatic cut out kettle. The open end, is pointed into the sink.

[Plummet]

<snip/>.

In the past, for long small sections, I have made a steam heating tube, simply attaching a flexible tube onto a stiff tube, which holds the pieces to be bent, the other end of the flexible attached to a non automatic cut out kettle. The open end, is pointed into the sink.

Or if you have a wallpaper srtipper/steamer...

 

Plummet

[Erfolg]

Plummet

 

What a great idea!

 

I am thinking of doing some more bending myself, and I have a Bosch stripper somewhere.

[Steve W-O]

Posted by Erfolg on 08/12/2011 22:32:42:

 

..................................................................and I have a Bosch stripper somewhere......

 

 

This hobby has interesting aspects

[Peter Miller]

First, the wood has to be able to bend, stiff wood will crack regardless.

 

Second. stick one edge of the wood down, leave to dry. Wet the outside of the wood and bend over while applying heat from a heat gun. If it is bendable it will form easily with this technique.

 

I use it on most of my designs.

 

Planking: Use wood  a little thicker than specified to allow for sanding down. Use a good razor plane to chamfer the edges. don't worry about small gaps, they can be filled later.

 

Put a plank on alternate sides to avoid building in a curve on the fuselage.

 

Looks terrible at first but great once shaped down. Use aliphatic resin as that sands down better. PVA will not sand down properly

Edited By Peter Miller on 09/12/2011 08:46:24

[andy watson]

Posted by Erfolg on 08/12/2011 22:03:43:

At a personal level, I worry about using any chemicals. I find that it is all to easy to damage clothing or household furniture by splashes etc. If the chemical can stain, I know, however careful I am, I will damage something, for me it is inevitable.

 

I have found that I can bend both plywood and balsa, to a diameter as small as 25mm.

 

Is it as flexible as ammonia, possibly not, yet done with just a little care not difficult.

 

In the past, for long small sections, I have made a steam heating tube, simply attaching a flexible tube onto a stiff tube, which holds the pieces to be bent, the other end of the flexible attached to a non automatic cut out kettle. The open end, is pointed into the sink.

 

 

I would have thought the risk of burns/scalds and water damage from your set up is far more likely than any danger from an ammonia based window cleaning fluid.

[Erfolg]

Much of what we do has some risk associated with what we do.

 

I know immediately if I put my hand into hot water, or get in the way of steam. I stop it.

 

If I damage a furnishing or clothing, I risk immediate hear damage, which does not diminish with time.

 

PM has his methods, you have yours and I prefer my own. As long as we are individually happy with our methods, it does not really matter. As long as the risks and benefits are understood.

[kc]

There is another way, if you put masking tape, tissue or even Solarfilm, tex, etc on the outer face you can bend wood around a much tighter curve. Try a sample test piece to see what I mean, 1 sample with tape and 1 without.

 

So just put masking tape on the balsa sheet first and see if it will bend round far enough without cracking. It's best to remove masking tape as soon as the glue dries otherwise the tape sticks on more after time.

Edited By kc on 09/12/2011 11:10:36

[Plummet]

Posted by Erfolg on 08/12/2011 22:32:42:

Plummet

 

What a great idea!

 

 

Please don't hold this against me. 'Great' is not really my style. But there again, those who have met me will probably agree that style is not my style either!

 

Plummet

[Myron Beaumont]

Quite often I have used two layers of 1/32 " sheet instead of one 1/16" layer .It will bend so easily especially if damp .Otherwise I would plank a la Peter Miller

[Alan Cantwell]

just thought that i would add to the saftey aspect of a couple of methods mentioned here, steaming, its easy, but care must be taken, that stuff lifts skin!! use thin oven gloves, and shield those eyes, ammonia is by far the best way to contort any wood to the shape you want, but, it MUST be done properly, i make--or made( havnt done this for a while!!) a bag up, out of sheet celly, folded the bottom over, and gripped it with bulldog clips, theses also kept the bag straight for when i hung it up, inserted the balsa-spruce-hardwood etc to be worked on, tipped in not a lot of the ammonia, then sealed the top of the bag, like the bottom, but used sellotape, give a geneorus overlap both ends, i wore a mask, saftey glasses, and some old clothes, never had a problem, to give you an example, when i had this method demoed to me, Les( passed on now, great guy) tied the piece of 1/4 square spruce into a knot, 2 hours later, it had regained its toghness, and looked wonderfull, i still have the piece, its a talking point sometimes

 

no mention has been made of the correct wood to be used for planking, this should come from the outside of the tree, across the grain, so it bends easy, but these days, no-one except the older end knows how to choose the stuff, if you buy from balsa cabin, or slec, they will do it for you, just tell them its for fuselage sheeting, and when you cut the sheet, one piece goes one side of the fuzz, next goes to the other side etc etc, in this way, the loads on the fuzz remain equal, simples, yes?

[heinkel]

Cheers everyone for the reply's, gonna go for the amonia method and see what happens, thanks for the tips