Over the last couple months I have been doing a lot of spraying of small
parts. I have been using an airbrush - which seems to work great for what
I am doing (plus the price was right!).
Recently I was fitting some brake line and I banged a wrench into the
lower A arm, which was painted about a month ago. The paint nicked and
exposed the primer! I sorta sat there and stared. I have spent a
lot of time painting things, and if it chips this easy - well - then I'm
gonna have to do it again (or say to hell with the nice finish and brush
on some Tremclad!).
I am wondering if I did something wrong or if maybe I am over reacting
a bit (to the chipping). The painting procedure I use is:
- clean to bare metal. I am doing this with the drano soak tank, and then
wire wheels on a grinder
- prime with "Mar-Hyde" self etching primer. I use the stuff in a can as
I am not sure what self etching primer woll do to the airbrush. I spray
3 to 4 coats (but the first is just a dusting).
- I then paint with enamel (the prodict is "R-M Super-Max Synthetic Enamel").
I am using a meduim fast reducer. I paint 3 coats, each getting thicker. I
leave about 10 mins between coats (the can says 25 min flash, but I'm not
getting any runs or sags. I did not add any hardener, but this is supposed
to be optional with this paint and I think it just speed up dry time
- the temperature in my garage ranges from 15 to 24 degrees, 'cause I never
got it properly insulated or heated (I rent the place)
- I found that about 35-45 psi works the best with the airbrush
I chose enamel (over an acrylic enamel) because I am scared of the isocyanates
or whatever - and enamel seems safer. I have a charcol respirator, but the
ventilation is quite poor. I couldn't find the "hammerite" stuff, and the
local Acklands (and others) gave me these "what are you talking about" looks
when I asked.
Anyway, I am sitting here with all these questions, like:
- how hard should this stuff get? (like should I be able to scratch it with
my fingernail?)
- does it get harder over time (like in a couple of months?)
- maybe I should have used the Imrom stuff. Would I still have the same
number of neurotransmitters?
- did I put on enough coats? Admittedly the airbrush probably sprays thinner
coats than a Real GunOA
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