Gap filling
 

For those that just love to use CA

Ever have a small gap when joining 2 pieces of wood, just rub some Cow Brand baking soda into the joint, brush off the excess and hit it with thin CA.

The joint is filled and is as strong as if it was a solid wood to wood joint.

It also sands a little easier the just CA. Be sure form remove all excess CA from the joint.

Filling gaps
 

I use balsa sanding dust. I have a 16 oz plastic cup I keep full of sanding dust, instead of brushing it all off into the trash. Fill small or large gaps with the dust and drip with thin CA.

Re: Filling gaps
 

Yes that works well too, my only problem is I can't seem to keep the balsa dust in one place, it's all over the place:p

Gap filling
 

You didn't mention it, but the baking soda also serves as a type of catalyst, the CA pops really fast! A little smoke, too, if you are susceptible to fumes, you might try something else, though...

I use it on almost all my joints while I am building - put a pinch of baking soda in the corner of the joint, thin CA it, and it forms it's own little fillet. Very strong, very minimal weight gain...

Done it for years, have NEVER had a plane fail in the air! (knock on wood!)

Seconded!