<<Let me make sure I understand...
I have a pancake compressor = not the smallest. but not enough to power
a spray gun, either.
Sound right? Sure would be less expensive than buying a new compressor!
It sounds perfect. You are only using the compressor part of the
operation to pressurize the air. I personally never thought of this
until Larry made the suggestion.
Think of it this way; my question that has been so ably answered was
that of how to use a small gun/compressor combo that can be portable
and taken to my jobs. I asked about using a bigger gun than my trim
gun, which works fine with my current pancake, but I was looking for a
bigger gun due to the small size capacity of the trim gun.
However, bigger guns need more CFMs. Here's the bite, and it will take
a little experimenting, but it should work fine. The bigger guns
suggested probably (actually) need about 6 cfm to operate at about 45 -
50 lbs of pressure. The pressure switch on my Bostitch compressor is
set at soemthing like 85 pounds; so plenty of pressure all the time
(and the compressor would run all the time) and the pressure itself
will never fall below what the gun needs to operate. HOWEVER, it will
not deliver the correct amount of cfms to push the paint out.
I must take my spray rig to the job, and must use it there to spray
metal doors, metal garage doors, metal sheds, security bars, etc.
with oil based coatings. Easy portability and an optimized delivery
system were what I was after. Without the portability issue, I have no
problem as I can spray from the larger shop compressor which lives in
the shop and is not at all portable. If it is latex, I already have a
nice airless setup for that. It shoots the thickest latex with no
thinning, so less coats of material. I was only asking about oil based
material delivery systems.
So... the great suggestion was made to put an additional tank on the
setup to store the pressurized air. If the compressor tank and the 2nd
tank are both pushed to 125 lbs of stored air, it will take much longer
for me to drain both tanks at 45-50 lbs of pressure required by the gun
(even at 6 cfm) than it would for me to drain the compressor only.
With a 6 gallon tank on the compressor, I didn't stand a chance.
However with 16 gallons using both tanks, I should get some reliable
spraying as I have such a greater volume of air under pressure.
I know I will have to let the compressor "catch up" but this is a
really hyperactive compressor that recovers very quickly. So I can
spray a fair amount, then when I get to a logical stopping point like
the end of run of security bars, a door face, whatever, I can stop
moment and then go on. I have developed a rhythm over the years from
taking my roofing gun out to do a repair when I have been stuck with my
compressor. Three or four shots, then it kicks in.... then three more
shots. I am patient and it works fine.
It spraying this way will work the hell out of the compressor, but then
I am only spraying a little at a time. I think with a little practice
and care, I can stay even with the setup.
I have my paint regulator/dryer setup as a stand alone unit that I take
along when I paint, and I will just put that on the end of the hose
coming from tank 2, not on the end of the compressor as I have it now
for my small gun.
Should work great.