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[email protected] nailshooter41@aol.com is offline
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Default Spraying Latex with HVLP

On May 26, 6:43*pm, "SonomaProducts.com" wrote:

Well, this gives me some hope. I thought if I could find an oil based
enamel it would be thinner but it seems I can only find it in quarts
and like rust oleum, which says for metal substrates only.

I'll try buying some better paint than the home depot stuff and see if
I can get something to work.


I would urge you to burn $35 - $40 and buy the best enamel you can get
your hands on (really, how much is your paint cost per project?) and
then sit down with a tablet and write down temperatures, a guess at
humidity, the amount of thinning, and the pressure you shoot at.
Before found a gauge I liked, I used to screw my pressure all the way
down to closed, and simply count the revolutions I used to open it. I
took a file and cut a groove in the knob when it was straight up so I
would have a reference. It worked well, but a gauge is better.

Interesting you say "cap" but Graco sells a needle and an insert. The
cap is reused but I assume it is the same, the orifice is in the
threaded insert. I got the biggest one they say my gun will push. The
next bigger turbine will push the biggest but maybe thinning will
help.


With most sprayers, a cap is part of the system. If you buy within
certain sizes, one cap will take care of different sized fluid
needles. So when you buy from different manufacturers, they think
differently; some say a fluid needle/opening will effectively use the
same sized air cap, which will blow out the same pattern from the same
holes. You adjust your finish from there.

Others think that using a 1mm needle size (the one I use for dyes)
requires a different air cap than the one you would use for latex,
typically a 1.7 to 1.6 mm fluid size. Different air caps not only
handle different amounts of air, but they also shoot different
patterns of air into the fluid stream. Since I have a Fuji, I tend to
call them air caps as they only sell a few needle sizes and they all
come with different caps.

Yes, I was at about 8 inches. I think I will try much less material
and slow down or do more passes to let it build.


I actually had to resort to a spacer stick to make sure I was spraying
at the correct distance. I would spray for a bit, then the gun would
move back to about 10" or so, which was great for my high pressure
stuff. Or even to 12". I tend to adjust the distance of the gun
based on the amount and look of the coating on the surface, which is
not the way to shoot HVLP.

I hope you post a follow up.

Robert