Kit building - what am I doing wrong?
 

I was wondering if anybody could advise me.

I have a TF Spit kit awaiting build and thought I would build my son a Guillows rubber band Spit as practise. It has been many years since I last built a model and that was with balsa cement.

Today I tried using CA for the first time and all I can say is what a royal b---s up. I was using grease proof paper to cover the plans and standard T-pins. I placed all the balsa required over the fin section and proceeded to put thin CA over the spots where the joins are. I probably put to much, wasn't sure how much to use.

I left it for a couple of minutes and on trying to remove the fin, I found it stuck fast to the grease paper and the grease paper to the plan and the plan to the board. The CA has seeped through the pin holes onto the plans and onto the board.

My questions are as follows:

1. How do you know hoe much CA to use???? (general rule of thumb)
2. What covering over the plans do you use that CA won't stick to?

I will be moving onto building with the Great Planes magnetic system for the TF Spit amd don't want a re-occurence of this on that, luckily I tried on the old board with pins first.

Cheers

Luis

RE: Kit building - what am I doing wrong?
 

Personally I build mostly with medium and don't use a lot of glue. Don't compare the amount you would use with a guillows kit and the hobby glue.

Thin Ca would be counted in drops and it disappears into the wood so you might have been tempted to keep adding more drops.

I build over wax paper and seldom do I have the paper stick to the plan.

Chances are with your first time through, you used too much glue based on your description. One thing to try if you want to keep using the thin CA is take a few scraps of balsa and practice joining it together with your CA, one drop at a time. That will let you get more used to how much you need.

Remember not to lean over the pieces while gluing as this stuff is rather toxic. You should ensure you have a well ventilated area.

Best of luck

Bob

RE: Kit building - what am I doing wrong?
 

Yea, definately switch to medium CA. And it doesn't take much!

Ditto on the waxed paper too.

RE: Kit building - what am I doing wrong?
 

Thanks for the input guys, does the medium CA wick into joints similar to the thin CA? Do you still need a tight join or can there be a slight gap?

I have been recommended to use polythene sheeting to cover the plans and building board, what do you guys recommend?

RE: Kit building - what am I doing wrong?
 

Tower sells rolls of plan protector which is thin plastic similar to the backing on monocote.I use it specifically because ca wont stick to it, although I use mostly carpenters glue now.

RE: Kit building - what am I doing wrong?
 

With ca you should have no gaps. I use yellow carpenters glue and put it on the joint before closing and it does not stick to the waxed paper, is cheap and sets enough to move in a coupla' hours. I use very little ca (Thin) Sigment is the old fashoned "airplane cement" and is very light and sands well. I use it when glueing blocks together that will be sanded to shape.

RE: Kit building - what am I doing wrong?
 

No matter what you use to protect your plans, if thin ca gets to the pin holes, it will glue the plans to the work surface. I try very hard to keep the pins away from the locations that I am going to glue.

Les

RE: Kit building - what am I doing wrong?
 

Medium CA will allow for some small gaps.

RE: Kit building - what am I doing wrong?
 

K guys, by jove I think I've got it. I continued with the little Spit for my son this afternoon and got the stab and fuse part done. What a difference, used medim CA for most joints, only used thin for tacking where neccesary and thick for larger gaps. I also used kicker quite liberally. One thing I will say though, is that even though I was working in a large ventilated area, I'm still reeling from the fumes of the stuff. I think I might have to put some sort of extraction system in place, :D.

I also purchased two packs of polythene plastic sheeting which works like a treat and also put the pins away from any glue joints.

So easy if you know how, thanks for all the info and recommendations.

Cheers

Luis

RE: Kit building - what am I doing wrong?
 

I use thin CA almost exclusively and don't have the "sticking" problem that you mentioned, so I think you probably over did it by a lot! ;)

For most smaller joints (say two pieces at 1/4" square), no more than two or three drops, through a fine tip extension, is necessary. (One drop through the standard CA bottle tip.)

I wouldn't use kicker except where necessary. I think it makes the glue joint more brittle, and it certainly adds to the fumes! [&:]
Dennis-

RE: Kit building - what am I doing wrong?
 

If you use thin you shouldnt need kicker if there are no gaps

RE: Kit building - what am I doing wrong?
 

You should never use kicker with thin... It makes it foam up.