george koller on thu 7 feb 02
Hello Clayart,
I'm setting up to leave for a couple of weeks and will
be away from the list. Several members have written
me directly about a Spray gun "system" which is being
sold for $70 in the newest harborfreight catalog.
There has been some confusion. The archives are full
of good advice for spray guns, and for compressors.
This "system" is different in many ways. It does not
require a compressor. It is a true HVLP. The listed
pressure is only 4 PSI. The nozzle size for the gun is
0.70" (which might be great for glazes).
HVLP stands for:
H)igh V)olume measured in CFM or cubic feet per minute
L)ow P)ressure measured in PSI = Pounds Per( Square) Inch
So this gun is the "real thing". It pushes a lot of CFM and at only
a few PSI. A big selling point for HVLP (was) that the material
being sprayed kind of "floats" out and thus does not "splash". High
pressure air will stir things a wet glaze up. Put your finger in front
of a compressed air HVLP and it is still using a lot of velocity to
atomize the liquid. This is different with true HVLP.
I wish I knew more. A big selling point for the first (expensive)
HVLP units was that because the liquid was "floated" out at less
velocity there is less overspray. thus less waste and less bad stuff
in the air. The Auto folks paid for the new guns, i think, based on
savings from these two factors alone.
These points are conjecture on my part, but I feel on pretty
solid ground:
1.) The big nozzle (this unit 0.7") allows for large amounts
of air. So could be very helpful in allowing some specks
of this or that thru the gun if desired.
2.) The pressure is not made from anything like a piston pump!
It has to be a motor and rotary system like the wrong end
of
a powerful vacuum system. Thus it does not have the
same
wear and tear, tanks, sticky valves, hot pistons and so
on.
Should last as long or longer than a small compressor, I
should think. It should also be much quieter (!)
I intend to order one, but will not have a chance to check
it out for several weeks. In the mean time all I can say is
that it COULD be a wonderful and priceworthy studio tool,
at least for low to medium usage. I'm eager to try one and
report about it.
Sure wish a trusted list "old bull" would buy one, test it,
and let us know what they think. I asked directly, there is
a 30 day return policy "on all items". They had today 450
of them in stock. The item # is #44677-3AVE.
I have no association.
HB tel is: 1-800-423-2567
www site is: harborfreight.com.
Again: I have not used or even seen this exact product. I
use other CenPneu products and my luck with them has been
very good. These are Manufactured in China. Good
materials and good design. Nothing from them, so far, has
been cheaply made.
I'll stop going on about this after one more thing. When I first
needed spray equipment for our glazes (for tiles) I was made
dizzy with options and was "priced out" of "true" HVLP by
the prices of over $1000. It is what I thought would be the
best quality. I didn't want to "compromise" on this. Not my
style with critical tools. But a potter advised me that Glaze
finishes are likely not subject to many of the same factors as
car paints / finishes. Hmmmm. I settled on buying what I
was told was a quality US made gun for several hundred dollars.
It worked OK. Then I needed wear replacement parts. The
kit for this gun, consisting of one needle and two washers,
was over $50 (back 5 years ago). By then I knew of harbor
freight and was seeing whole guns for $39.99. Geez. Why
not try them? (give me a break! quality is quality but a rip
off is a rip off also?! or not? $50 for a needle? is it gold
or something?) So I tried the HB gun. It was not JUST as good.
I swear to you, it was BETTER. It was lighter. Clogged less,
and felt better. They also last longer.
By the by: one of my favorite tricks has been to keep two of these
guns at the ready. One for light, and one for all dark. Keeps the
dark stuff out of the light stuff. Dark on dark no particular problem.
My background on spray guns:
I only started using spray guns about 6 years ago but had to use
them heavily (we did multiple layers on lots of tiles). We mix
our own glazes and use CMC for thickening. We strain the glazes
at 300 mesh to get good spraying characteristics. We always
wash the guns out with lots of water between uses.
Sure hope this helps somebody. I'm going to be off-list starting
(likely) saturday so maybe somebody else that feels they know
something about this could help along...
Best,
George Koller
Sturgeon Bay, WI - Door County
PS
Off to meet my "Alfred connection" at the Northport, Michigan
studio. A wonderful drive up and over the Mackinaw bridge.
Depending on what we learn may go on to Alfred to meet the
folks I will be working with on our tile project. We are using
the metal sulfates as colorants by adding it to a colorless base
glaze(that is sprayed on). Some H&R Johnson bisque tiles,
some stoneware, some porcelain, and even some "glass".
Basically we are doing the Kurt Wild decorating technique
using computers and various whirlygigs. Someday get me
a EPS file and spritz you out the tiles. 100 feet sq? no problem!
tomorrow? well maybe next week.....
I'm a displaced programmer trying to promote myself to a starving
artist. So far so good. Love you folks. Clayart has opened a lot
of doors for me. Tony H. told somebody what I'm doing that some
sign company in Virginia found out that...... and I'm off to work
at Alfred - MECCA!. Learned about Kurt Wild from Mel. Mel
is to blame for everything. Up there in long johns and pink
bunny slippers just laughing at it all. As the wheel turns....
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