tiredofspam wrote:

Reading your info, you appear to have a lot of experience.
What I don't understand is what am I doing wrong if I shoot with
shellac successfully with an hvlp gun. I don't have a problem
cleaning. Just throw alcohol thru, open the valves to throw a lot of
alcohol
thru and your done. I don't use brushes to clean, I just run it
through. When I reload it melts any light coating that might be there.

So what am I doing wrong?


Apparently - nothing. Some materials like shellac may well clean well - in
some guns, just by shooting the respective solvent through them. Other
materials will come back to bite you in the ass with that technique.
Catalytic finishes won't be as nice to your gun, if you ever take up
shooting those. Back in the day when lacquer was king, a lot of guys used
to just shoot lacquer thinner through their gun to clean it, and all was
well - for a while. Like your experience, if there was anything left in the
gun, the next time you used it, the residue would blow out as the new
material burned into it. Sorta... Stuff built up over time and eventually
the gun started misbehaving. So, ya stripped it down, soaked it in thinner
or carb cleaner for a couple of days, and went at it with brushes and picks.
Royal PITA.

Maybe you won't hit this point with shellac (I don't shoot it, so I don't
really know how it behaves), and maybe your gun will tolerate more build up
than another gun will. If so - good for you! If however, you begin to see
your gun behaving erratically, or in an unfamiliar way, the first place you
might want to consider looking is at build up.

--

-Mike-