Balsa Sealing Question

A good thing, which is also *cheap*, as well as easy to work with....

Testor's Dullcoat (in the bottle, to be applied with a brush), with talcum powder mixed in.

Of course, this assumes that you are not also wishing to preserve the original wood-grain of the pieces....

Robert:

As an old balsa wood modeller I can answer this one. Your best bet is to go to a hardware store and buy some clear lacquer and some lacquer thinner. For the first coat, pour a little of the lacquer in a small container and thin it about 3 parts lacquer to one part thinner. This will soak into the wood grain a bit and will "raise the hair" of the grain, as we used to say. When dry (about 1/2 hour) sand it till just smooth with medium to fine sand paper. Next, pour a small amount of the lacquer into a container and add some talcum powder to it. Not a lot, just enough to make it a cloudy solution. This will act as a filler to fill in the wood grain. Paint, allow to dry and use that fine sandpaper again. You may have to do two or three coats depending upon how coarse grained your particular piece of balsa wood is. Then follow up with a couple of coats of straight lacquer, again sanding after each. With time and a little practice you can get a finish like glass with this approach.

Bill Shuey

I have found Hobby Poxy Fast fill wood grain filler works great. Apply 4 or

...way back when I used to do R/C kits, buturate dope with talcum powder mixed in it made a good cheap balsa filler.

But the one you saw was probably filled with epoxy resin and microballoons. About one step removed from fiberglass...and probably more waterproof.

Two part epoxy resin was the way to go.

Hard, smooth and waterproof in no time.

Hobby stores carry the stuff, also hardware stores carry it sometimes.

FredD

You can always (Sigh!) go to your "Big Box" store such as Lowes's or Home Depot and buy a quart of "Sanding Sealer" ~ Give it a coat, then Sand, then another coat, sand, etc. until you get that hard, polished base for whatever paint you are using.

~Rick Fluke

Sanding sealer.

Go to your local paint store and get a can of this (sanding sealer) Used in furniture refinishing to seal all the ppores in the wood, and enables you to get a mirror finish with your topcoat (s) Be prepared for some sanding with a few grits to get that mirror finish.

While I am an old balsa bug, I only use balsa on flying models, using basswood now on non-flying stuff. I also used to use lacquer or dope for a sanding seal, but with the advent of urethane varnishes, I find I can thin urethane 1:1 and it makes a fine sealer. I prefer that now as I use urethane varnish for lots of other things, and use little lacquer for other things (though I keep a stock of lacquer thinner as a great solvent and cleaner.