Thread: Airbrush Tech
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Old 12-18-2008, 10:34 AM
luke strawwalker's Avatar
luke strawwalker luke strawwalker is offline
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Quote:
Originally Posted by ScaleNut
I agree with Micro, a touch up gun is a good step up, when you get to the 4"
dia range, you can really lay down some paint.

OK,something about basecoating/primer.

I don't use an airbrush to prime or basecoat an entire rocket.
this is where spraycans work great.

primer is too high in solids and size of pigment to be airbrush friendly
automotive primer is superior to any airbrush primer, you won't find much airbrush sandable primer ( I haven't seen any)
plus I'm not worried about the finish of primer because I am going to sand it .
canned primer is the choice for me

I always basecoat my rockets with a spray of (krylon) gloss white (or black)
it shows every imperfection if I want to go anal on the finish
it provides a smooth clean white(or) black canvas to paint and nothing brings out colors like a white basecoat.
also if you like to wetsand ...paint is the best surface. wetsanding primer is often a waste of time unless you are capable of spraying a perfect coat of paint from a can with zero flaws or blushing on top of it. plus primer is absorbent...it 's risky to get it wet over a paper substrate.. if it's a fibergalss tube .. no problem.

I let spraycans do the "grunt work"
than hook up the airbrush.


That's interesting... I've been using the Walmart house brand Colorplace 97 cent a can (mostly gray but red for hi-dep) primer and wet sanding it on regular paper tube and balsa finned rocket (papered fins and some just with Elmers wood filler) and haven't had ANY problems from water...

I sand with at least two progressively finer grades, and then a real fine paper if needed to get any scratches or other detectable imperfections out before I prime... I tack the rocket off with a cloth and then run a clean fingertip over every square inch feeling for imperfections, and I also will hold it up to a light and observe the reflected 'glint' for imperfections... I don't go super anal before priming, but the smoother you get it before priming the easier it is to prime. I usually put two or three coats of rattlecan primer on, let it dry overnight, then do a nice wetsanding on it with 800 or 1000 paper. If I had some scratches or something that I decided to fill with primer and put a heavy primer coat on, sometimes I'll dry sand the primer first with 600 paper to get most of it off... and reprime any spots that need attention if need be, and then wet sand it all out. What I do is, I keep a bowl of water handy and an old towel that I rest the rocket on, and wash/rub my paper in the water to release the paint dust, and then usually slap my paper gently against the bowl side to get most of the water off before returning to the rocket. If the paper is too dry it won't sand well, but I don't want water running everywhere either... usually if I need a bit of water I just dip a finger in and drip it on the area I'm sanding... I wash the paper about every minute or so... watch as you sand-- the water on the surface starts turning into a thin watery 'mud' as you sand and liberate more primer, and when that 'mud' starts to thicken up, it's time to wash the paper and wipe the sanding mud off the tube (usually keep a paper towel handy for that)

Using this method has worked well for me and if you really work at it for a couple hours you can actually make the primer shine just like a color layer... what I like about it is, if you put the color layer on light and even in a couple coats or so, it will lay down beautifully and you don't even have to color sand... it will shine like a new dime all on it's own...

Good luck! OL JR
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