New to scratch building!
 

I'm new to scratch building and I have a huge problem I need solved. I'm building a custom airplane that has a cylinder shaped fuselage. I'm using balsa wood sheets as covering for the fuse and I need help!! How do I bend the wood to make it fit the fuse? And what's best to glue the balsa sheeting to my fuselhe frame? I heard boiling the balsa is great for making it bend but glueing wet balsa is almost impossible! Someone please help!!!

RE: New to scratch building!
 

You dont have to boil it, I personally have never heard of that. What I think is most common is to soak the balsa wood in regular old water. Once it has been soaking for a little while you can pull it out and bend it anywhere you want. When I have balsa that is already partially glued onto the fuse and it still needs bending, like around a round nose or whatever, you can grab a cloth or a big wad of paper towls and soak it in water. Just go back inforth over the area that you want to bend and shape with the wet cloth or towl and it will slowly start to bend around a curve. As for glueing wet balsa, the only thing I have used to glue it while wet is CA (cyanoaccylate) glue and kicker. I think if you use any other kind of glue that is slower drying you will need to get clamps and secure it in place until it thouroughly dries.

If you have to do some serious bending around really tight curves, the best chemical to use is amonia. If you soak wood in amonia for a little bit, that is the best chemical I think that will soften the wood to bend it anywhere you want. Windex is a good second or substitue because it has amonia in it.

David

RE: New to scratch building!
 

The front half of this plane was sheeted with 3/32 and from behind the cockpit I used 1/16. I used a squirt bottle of water blended 50/50 with ammonia, then rubber banded the wood and let it take it's own shape. I used medium CA for my sheeting. Before I glued it down I shot it with my squirt bottle again so it bends well for final gluing. There are a number of ways but damp wood and CA work pretty well. If you posted in the scratch builoding forum a lot of guys will have different ways of doing things but this is my old stand by.;)

RE: New to scratch building!
 

Hey Gene who is that ugly guy in the first picture. :D:D:D

RE: New to scratch building!
 

I 2nd the amonia + water treatment. I use sometimes ace elastic wrap doing the turtle deck. A little wider than rubber bands and doesn't have a tendency to dent the balsa. Either way works and I have used both. I enjoy scratch building and then seeing that sucker actually fly.

RE: New to scratch building!
 

Actually, vinegar is better than ammonia. Think back of the chicken legs you softened as a child in science class by soaking in vinegar. Pat the wood dry with a paper towel, then bend around the bulkhead. About the only glue that will attach wet balsa quickly and easily is CA and kicker.

RE: New to scratch building!
 

Well wasn't aware of the vinegar thing. I will certainly give that a try. Smells better than amonia. Never did the chicken leg thing in HS. I went to a city school:D:D:D

RE: New to scratch building!
 

Do you use the vinegar full strength?

RE: New to scratch building!
 

I do. Keep testing the wood until it has the flexibility you need. I simply use a 1" brush to wet the wood on both sides. Don't soak it. An alternative to trying to glue wet balsa: form the balsa into place and tape it down. Come back a couple days later when it's dry, take the tape off and glue.

RE: New to scratch building!
 

Do you have to have kicker for the CA? Can i just use regular superglue and wait the 3 minutes?

RE: New to scratch building!
 

The kicker gives you the instant set for the CA. That way you don't have to wait the three minutes.. :D Once formed and glued, you can move on.

CGr.

RE: New to scratch building!
 

I've found bleach-water (about 3:1 water:bleach) to have a rather nice ancillary effect:

Not only does it work well for softening/forming the balsa...but it also kicks the CA. :)

RE: New to scratch building!
 

I think you could definately try that. The only reason you use the kicker is so it will immediatley cure. If you dont use it you just half to hold the balsa wood in its shape until the glue dries which might take a little longer. You can check it every now and then by releasing a little pressure and if it starts poping back up, keep holding it.

RE: New to scratch building!
 

CA does not like to cure in wet wood. The kicker helps it along.

RE: New to scratch building!
 

i have never used kicker so im sorry if im kinda lost:D. How much is the kicker usually?

RE: New to scratch building!
 

Cost wise or the amount?

Cost.. just about the same amount as the CA.

If the amount, it's a spritz sort of spray. You join the two pieces of wood (three.. whatever) then hit it with your few drops of CA then immediately spray it with the CA Kicker spritz. You can almost watch it zap and set.

CGr.

RE: New to scratch building!
 

One note of caution about using the CA Accelerator/Kicker....

Be careful not to have any CA on your hands, or get your fingers into the CA in the joint.   It gets HOT....burn your skin hot.  Go ahead...ask me how I know.  :eek:

RE: New to scratch building!
 

"Be careful not to have any CA on your hands, or get your fingers into the CA in the joint. It gets HOT....burn your skin hot. Go ahead...ask me how I know. "

A big +1 there! Also, let the CA soak in for a second or so before hitting it with the kicker. And don't soak it, all you need is a light spritz.

RE: New to scratch building!
 

I have never used kicker as a general rule. Medium CA is fast enough for me. When I glue, the wood isn't dripping wet but it is very damp, I only spray the outside. Rubber bands do tend to dent the wood so if you come up with something wider like Gene mentioned and it works for you then you would be better off. I have only used the ammonia and water so I can't coment on the other brews. Ugly I can take, just watch the old jokes!!!:D I showed the photo with me in it to show the planes size and to show that you can sheet a round fuse without too much trouble, even with thicker wood. As shown, that plane was boned up for use with a 1.20 four stroke, after the photo was taken I added hard wood stringers from the fire wall to behind the cockpit because I went with a gas 2.4 Brison so there was a need for some added strength. I love sheeting and like the looks of a plane that has been sheeted, just something about the way they come out so smooth. Maybe I'm just silly but I like to glass them too, the Sukhoi was just sheeted and covered though.

RE: New to scratch building!
 

You can always lay the fuse up with balsa strips about 1/2" wide. Sand to suit.

RE: New to scratch building!
 

This is true, I have a couple of those way cool strip cutters and you can angle the cuts so the sheets line up without the flat gap. Strip sheeting is something I do on very tight curves. With the cutter angled you use almost no filler.

RE: New to scratch building!
 

soak it with rubbing alcohol...bend and rubber band it on,,the alcohol will dry quicker than water or vinegar will.. then just glue it where it is with ca when it dries....Rog

RE: New to scratch building!
 

Vineager works on chicken legs by removing calcium. Did you notice the chicken legs never reharden. Personally I wouldn't use it. I use plain water.-BW

RE: New to scratch building!
 

Nope, never knew that. You contry boys in Millington had all the fun. Us Grand Blanc boys were city slickers.

RE: New to scratch building!
 

Never had no chickens out here in the boonies...got some cows though. But we did have alotta fun...You city slickers couldn't launch rockets in your front yard like we could...lol.-BW