high build primer

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ericm541

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Looking for a good high build easy to sand primer, any suggestions. I've tried quite a few, they end up not filling and clog the sand paper.
 
Not for nothing, but in my experience, paints only clog the paper when it isn't fully cured...
 
Do NOT Use Kilz's it is NOT a real primer but a drywall filler.

Just about any old rattle can auto primer will fill and sand easily as long as it is cured, Use the "Sniff Test": With your Nose on the surface of the rocket if you smell anything the Paint or Primer has NOT fully cured. Wait awhile longer.

I use the cheapest Grey Auto primer I can find, Spray on 3 heavy wet coat with about 5 minutes between coats then allow the rocket to out gas overnight. Next evening it's generally "Sniff Test" cured enough to dry sand with 220 to 320grit sandpaper without loading up the grit. If I reach wood or some of the spiral gap still show, repeat the process usually completely fill all grain and body seams with 2 applications of 3 wet coats. Currently I'm using Walmart "Fresh & easy" Grey Auto primer. .83 to 97 cents per 12oz can. with outstanding results.

If you want to spend a good bit more for a high build primer, I second the recommendation and use of Duplicolor High Build primer. It's just way more expensive for something we're going to sand most of off;)
 
Acme/Finish 1 FP-410, a catalyzed primer-filler. You will need a gun, compressor, and PPE so this may be a non-starter for you. IMHO, it is absolutely the best: high build, quick drying, easy to sand and tough as nails.
 
Remember, you need to use the same primer as the top coat, some chemicals dont play well with others, example: krylon primer and duplicolor top coat = not good.
 
Acme/Finish 1 FP-410, a catalyzed primer-filler. You will need a gun, compressor, and PPE so this may be a non-starter for you. IMHO, it is absolutely the best: high build, quick drying, easy to sand and tough as nails.

I have 2 decent spay guns, good compressor and the space to do it. I haven't worked up to catalyzed paints though, i could be wrong but a typical respirator won't work you need a helm with a different air supply. I'm picking up where i left off after having to stop rocketry several years ago, a lot of new products. Back then i used a rattle can primer that was everything filled spirals sanded easy, if only i could remember the brand. I have not tried duplicolor, see how that works.
 
I bought a 3M full face respirator a while back to replace the half-face I had used. it has removable face shield covers so that you done ruin the primary shield. You can choose the respirator cartridges based on your application. It was not cheap, but what price to keeps your health........
 
I've typically used rattle cans for all my rockets, got a couple sprayers tried it out years ago with water based paint. Wasn't worth it in the end for me with the mess,small rockets and krylon rattle can was doing fine. My current rocket project is very big compared to previous ones, might be worth looking into spraying again. Thanks
 
Full face respirator is not enough for spraying most catalyzed paints. To be safe you need a full body suit and a fresh air system. That's why I don't use catalyzed eurethane enamel. That's what's used on all new cars and it's the best paint there is, but it is very toxic. It can be absorbed through your skin and if the hardener gets in your lungs, it's bad.
 
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