skaffgeorge2
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Generally speaking, how many coats of primer do you put on before sanding?And how long do you usually let it dry for?
Primer question
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2-4, and to the point where it's not tacky or smelly. Most primers are lacquer based and dry very very fast, and temp and humidity of the day will all change how long you need to wait. If unsure, hit a small spot (or make an intentional test overspray spot) with fine sandpaper, if it makes dust, you're golden, if it gums the paper, put it aside and wait longer.
skaffgeorge2
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Yeah, that sounds about right.Just hit my Laser X with the first coat yesterday morning so I've got at least two more to go.Paint seemsto be fine despite it's being hot and muggy here lately.Coverage seems to be fine except there's some excess buildup around the vanes at the base.
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That depends entirely on what I'm trying to achieve.
If I'm spraying primer just for final coat adhesion (e.g.: onto fiberglass tube), then just one will do. Two if it's a big tube and I miss spots.
If I'm spraying primer to fill in imperfections in the tube (e.g.: spirals in a paper tube), then as many as it takes to spray-dry-sand-(run a finger along the tube and see if spirals are still present). Repeat as necessary. Usually takes 3-5 cycles.
That depends entirely on the quality and chemistry of the primer, as well as the ambient temps and humidity.
Acrylic and lacquer paints and primers dry in minutes (2-20 mins, depending on brand).
Enamel (cheaper paints from HD or WM) take 1-2 hours to dry before you can sand them.
All types take longer to dry in humid and colder environments.
More here:
https://www.rocketryforum.com/threads/newway-n-22-night-storm-build-thread.180716/post-2453610
HTH,
a
I've been using sandable rattle can, usually just one or two coats with that. Normal primer usually 2 to 3 times, then sand. After that I sand every time I spray primer or paint if needed. But I've been using the Rustoleum 2X paint/primer it works out really well George.
skaffgeorge2
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Been using good old fashionedTestor's grey spray primer.Actually been working pretty well.Just did the first coat on the Laser yesterday,this thing is gonna look like a showroom model by the time it's done.And the Vikings look good even naked.
Ok cool man! Look forward to meeting you and Chris and launching!
I use Rusto grey Automotive Primer. It dries very fast. Can spray one day and sand the next or sooner. I spray the primer, wait 10 minutes and do another coat, wait 10 minutes and do another coat, etc. I'll do 5 or 6 coats in an hour. On mid-sized projects that is about 1/2 a can. On larger projects it's a whole can. It's recommended on the can to do many light coats every few minutes and to do it in one hour. Sometimes the primer dries fast enough that I can paint many coats at one time. I just keep walking around the rocket spraying.
skaffgeorge2
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Yeah, I E-mailedhim yesterday but he hasn't gotten back to me yet.
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That's what I've been using too here and there, works fantastic. It's not near the spray cans at Walmart, it's over in the automotive section, took me a second to realize that..lol...
Really depends on which primer you are using. If you are using normal (not high build) then you will need to put on a ton of coats before the surface will be smooth. If you are using something like Rustoleum then you're going to need 3 or 4 coats.
I use SEM high build 99% of the time and 2 coats is more than enough on all but the worst surfaces.
I use SEM high build 99% of the time and 2 coats is more than enough on all but the worst surfaces.
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With Kilz or other thick primer, usually 1-2 coats. First to smooth, second to cover the fuzzies from the first, and then maybe a spot touch-up. If you want to get rid of spirals without filler, you'll have more coats.
If fiberglass, and with the right paint, I've been known to not prime at all (but usually with very specific opaque colors that cover well, like black/blue/red/orange).
If fiberglass, and with the right paint, I've been known to not prime at all (but usually with very specific opaque colors that cover well, like black/blue/red/orange).
