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Best for Balsa?

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Fireman55

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What's the best way to finish balsa. After a good sand before I begin I use wood hardner. Then another light sand before painting.
 

Micromeister

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Can I ask you to visit www.narhams.org website library look for Tech-tips 002-005, these downloadable pdf files will take you from raw balsa or cardboard to babies butt smooth finished models with a number of optional tip and techniques along the way;)
Hope this helps, it saves a lot of repeat typing:)
 

luke strawwalker

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What's the best way to finish balsa. After a good sand before I begin I use wood hardner. Then another light sand before painting.
Here's what I do... and it works pretty darn well...

As soon as I get the nosecone out of the package, (transitions too if applicable) and test fitted to the tube(s), I take them straight outside and coat them with thin CA to harden the balsa. CA cures almost instantly and gives about as much protection as wood hardener would...

Next, a good sanding with 220 grit to take off the hardened 'fuzz' and grit left behind by the CA treatment. Doesn't take long to get it nice and fairly smooth. You don't need it glassy, just make it fairly smooth. I then brush on a coat of Elmer's wood filler, thinned with water to about the consistency of mustard, or maybe a hair thinner. That will dry within about 30 minutes or so, which can be spent doing other stuff on the rocket's construction. When dry, it's another 220 sanding to take off almost all the filler, which should leave the nosecone NICE and smooth-- any remaining grain or blemishes can get a refilling with thinned Elmer's again if necessary, but usually it's not needed, and a resanding with 220 if needed. Now she's ready for primer. I shoot two coats of Walmart gray or red Colorplace primer on it and allow to dry for an hour or so. Then hit it with the 220 again, sanding lightly in circles to get it nice and smooth. Any obvious blemishes will get another coat or two of primer, and another sanding when dry. Then I switch to 600 grit wet sanding, using a small bowl of water to wet and clean the paper, daubed on a towel to minimize the amount of water on the part, and sanding lightly in circles while gently turning the part in my hand to eliminate sanding swirls. I use a paper towel to take off the 'sanding mud'. Once the nosecone is slick and smooth to the touch, I hold it up so the light can 'glint' off it and rotate it slowly looking for imperfections, which I gently sand away. Once done, I give it awhile to dry thoroughly while I work on other parts of the rocket. The whole thing is usually given this treatment and ready for paint.

The nosecone/transitions will come out looking just like plastic if you do it right! The paint will look great if you shoot it on there right and I haven't had to wet sand a color coat yet and have pretty good results! :)

Good luck and hope this helps! OL JR :)
 
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