Originally Posted by Doug Sams

Hi, Jeff,

Yes, it's brush on. It's alcohol based, so it dries fast, but pick up some ethanol for clean-up. The Zinsser is about 10$/quart, but equal to many, many $4 cans of spray primer. It's also available in a spray can, but I don't like it - it comes out way too fast.

When brushing it on, because it dries fast, you will get brush strokes if you don't keep your brush wet.

I like to put it down as the first layer over the balsa and paper after the glues (& glass, if applicable). I then put the FnF (filler) over the Zinsser for fillets and for filling the grain and spirals. In fact, I've gotten to where I just about don't even bother with the grain and spirals. With a couple coats of rattle can primer over the Zinsser, most of that stuff is filled.

There is no sure fire one-coat grain filler. It comes down to how picky you are. I find that nearly four fill/sand passes are needed to completely fill balsa no matter what I use. Sometimes I use Zinsser, then thinned FnF, then rattle can primer, then touch up with more FnF followed by more rattle can; sometimes it's two coats of Zinsser, then two coats of rattle can; sometimes it's something else Sometimes, I just put one coat of primer down, then paint. I can make it look like molded plastic when I'm in the mood, but, as they say, there comes a time to shoot the engineers and start production, or, in our case, fly that mutha

I did have one lady ask me at a launch years ago if my rocket was made of plastic I explained that it was balsa and paper. She got quite wide eyed after that




Doug

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