Diluted Fill N Finish and warping fins?

Hello,
I have been using Fill N Finish diluted with water as a balsa sealer on my model rockets. The last two rockets I have noticed the fins are warping slightly after I brush on the Fill N Finish. Anyone notice this? What can you do to avoid this situation?

Thanks in advance,
Brian

 

[WombatSoup]

Cover both sides of the fin at the same time.

If you only do one side, that side of the fin absorbs too much moisture and the fin warps. Sometimes you can get the whole fin wet and put it under a book (or something heavy and flat) and it will flatten out the fin - works better with balsa than ply.

 

[cmmeyers]

I've been turned on to the "dry rub" method of applying fill 'n finish. No warping, and you can begin sanding almost immediately after applying.

 

[astronboy]

Are the fins attached to the rocket when they are warping? I have never had this happen if the fins are glued on....

 

[Stymye]

I tend to dilute it very little, or dry rub

 

It's after the fins are glued on. I am building a Deuce's Wild kit. I glued the fins on with a guide and everything was lined up good. Then after I put the diluted Fill N Finish on the fins, I noticed one end (farthest away from the body tube) of one of the fins is slightly warped. What is the dry method?


Brian

 

[bsexton]

Use water sparingly and coat both sides of fin or the dry rub process.