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Mike Marlow[_2_] Mike Marlow[_2_] is offline
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Default Paint spray guns (air)....

Existential Angst wrote:


We had an electric/airless Wagner ditty hanging around for quite some
time, never used, and yesterday just could not get it to work, not
with paint, water, nada. And what a racket it makes!
And I could see, from the pita clean up, that even if it did work, it
would proly never work again, from clogs, etc. The guys at my
lumberyard were no fan of this airless-wagner stuff.


Yeah - the old ones were kind of clunky and they sure were loud! Don't know
about the current ones.


So it turns out I had Husky siphon-feed air spray gun stored away,
never used (like http://tinyurl.com/93p396e , closer to the #6500,
actual sku # 515-507)
so I hooked up one of them bitty pressure regulators (like
http://tinyurl.com/clzjlcu
, except with a separator), and WaLa, I'm spraying paint!!! Water
based.
This husky gun seems to be "high pressure", as opposed to HVLP, but I
put a regulator on it anyway, as the box mentioned cfm at 40 psi, so
I figgered the operating pressure would be in the area of 40 psi, and
my compressor is 80-110 psi.
That 40 drops to 20 psi upon spraying, but this range seems to feel
right for the gun -- with all 5 mins of my paint spraying experience.


Turn it up. With a gun like that you'll probably want around 40psi at the
gun while shooting. It does depend on the material you are shooting and
some guns shoot heavier stuff better than others, but trial and error will
be your friend. It's not HVLP, so at 20psi at the gun, you're way under the
desired pressure - always set pressure with the trigger pulled.


So there seems to be basically 3 adjustments: 1. inlet pressure 2.
knob controlling trigger "depth" or spray amount and 3. a knob
above that for the "fan" or spread of the spray.


Correct. The fan size adjustment is kind of logical - you set the fan size
for what you need. If you're trying to shoot a very small area (perhaps,
shooting into a nook or a corner...) you'd turn the fan down to a very small
(smallest) pattern, whereas if you are shooting full surfaces, you'd open
the fan up. For most work, just open the fan all the way.

For the delivery adjustment - To set this adjustment, turn the adjustment
knob out and pull back the trigger. Turn the delivery adjustment in until
you feel contact with the trigger. This will give you the maximum delivery
rate and will be fine for most all of your needs. I usually give the
adjustment an extra 1/4 turn in at this point - your choice.


As well as the
"wings" of the nozzle for hor'zl or vert direction to the spray.
And viscosity of the paint, which seems to need to be on the thin
side.


Yup - it's suction so the design of the gun will dictate how thick the
material can be in order for it to pick it up and atomize it. One of the
best guns ever built for heavier materials is the old Binks Model 7. I
shoot Rustoleum straight out of the can with no reducers with my Model 7 and
it goes on like glass. Few guns - especially the cheap ones can match the
Model 7 in this regard. Keep your eyes on yard sales - Model 7's show up
all over the place and they're pretty cheap. You can still get rebuild kits
for them for around $40 that will make the gun perform like brand new.


Does HVLP have any advantages over non-hvlp?


Less overspray which results in less waste and lowered costs. The
disadvantage is the demand for a better compressor since conversion guns
require a higher SCFM rate than a basic suction gun. Gun specs will dictate
this.

Can a high pressure gun be "converted" to a HVLP gun by simply
dialing in lower pressure and perhaps adjusting the above knobs
somehow?


Nope. Don't even waste your time trying.

Would another nozzle be required? I haven't seen replacement nozzles
for this spray gun. Are these generic/available?


Nope. Don't even waste your time trying.


Seems to lay down nice fine layers, which iiuc is much better for
adhesion, as opposed to thick brush layers. Will have to lay down
several of these, tho.


Yup - spraying is a process of laying down thinner coats. The advantage is
that they tack faster, and you can lay down many coats in a short amount of
time, and you'll have a nicer finish when you are done.


Does a gravity fed gun have any advantages over the siphon?


Yeah... and No. For the kind of work that I'm under the impression you're
after - Not really. There are the obvious things such as working in odd
positions, but you can spray with a suction gun in a near upside down
position so that's not really as big a benefit as you might first think.
Gravity guns are easier to clean, but again - only marginally so. I still
shoot my suction guns a lot - especially for primers and heavy materials. I
have no need to move off of them - and I do have gravity guns as well.

Do the more expensive "airless" sprayers have advantages over air,
besides not needing a sep. compressor/air tank?
I see they use high psi like a power washer, but I don't know if this
is necessarily an advantage -- seems like just another thing to
break. The air guns seem inherently simple, reliable.


Sorry - not up to speed on the new airless guns.

I think this gun is going to work well, just that filling up the quart
container is going to be a bit of a pain.
Relatively easy to clean.
If I added a hose to this gun, could I siphon right from a paint can
on the ground or perhaps on a cart?


Maybe - but probably not, unless the pot is pressurized.

I hear people knock Husky as a crap HD brand, but I have one of their
compressors (26 gal), very quiet (for a compressor), heads and
shoulders above Sears compressors. The pressure regulator is a
little crude, but other than that, it's been bery bery good to me.
Similarly, this husky spray gun does not seem chintzy at all, almost
heavy duty.


There's nothing wrong with any of the Husky equipment and specifically,
there's nothing wrong with the gun you own, for the type of use I think I
understand you to put it to. I've painted cars with some dirt cheap guns
and turned out a perfectly acceptable paint job. I've also thrown some out
because I could not do anything to get a decent spray out of them. Harbor
Freight sells a knock off of the Binks Model 7 for around $40 (I think...)
that I have suggested people buy in the past. They work like a top and
parts are interchangeable with the Model 7. A complete copy of the Model 7.
Cheap does not have to mean junk. If you can get a good atomized pattern
out of your gun, then it's fine. It's like any other gun - you learn how to
work within its limitations and its characteristics.


Appreciate any heads up, as I'm going to be doing some real painting
tomorrow, on T1-11, which is difficult to brush or roller.


The biggest hurdle in shooting paint is to resist the temptation to get on
it again before the first coat has sufficient time to tack. Get on it too
soon and you'll enjoy that modern look... the artistic stuff. Some call
it... runs...

--

-Mike-