Andi Runt on thu 29 oct 98
Hi Clayarters,
To any of you experienced in spraying glazes: I'd love a verbal
crash-course in spraying, addressing such issues as - do you need to wax
feet? Pour or spray insides of vases? several light coats or one-two
heavier coats? Glaze consistency? Any other application / clean-up
techniques / tips / tricks? I haven't been able to find someone to watch
spraying, so maybe a verbal description would give me a jump on the
learning curve. TIA (Addicted to Clayart - loved Joe Molinaro's article
"Cyberclay" in latest CM)
Andi in PA. where the petunias are still blooming at Halloween!
Andi Runt
Impressions in Pottery
State College, PA
jpri@email. psu.edu
Marvin S. Flowerman on sat 31 oct 98
Dear Andi,
I do a fair amount of spraying.
Given a good, well-ventilated (i.e. exhaust system) spraying booth, and a
nozzle producing a fine mist spray, you need to (a) wax the feet, (b) spray a
section, turn the piece and spray the next section and so on, always spraying
lightly and allowing each section to gray-out, i.e., dry sufficiently, before
you spray on a second coating. You should judge that you have enough coverage
when the dried surface looks like fine sandpaper; let the piece dry out for a
bit in the booth, then remove carefully, and mop off the feet which should not
be a problem if they were waxed well and the wax was allowed to dry thoroughly
before it was applied to the feet.
I hope this helps. Any further questions you can contact me through the list.
Good luck.
Marvin Flowerman
Marcia Selsor on sun 1 nov 98
Dear Andy,
My students spray pieces that are too big to dip. Depending on your
sprayer, the glaze can be the same consistency as for dipping and
pouring. Sieve first to avoid clogging. Usually pour the inside first
and let it dry. Several thinner coats give a more even application than
a heavy coat which will get runs. Waxing is not so critical because the
air pressure tends not to get much glaze where the foot meets the
floor.Wipe clean anyway. Use in a vented situation as glaze dusts are
not healthy to breath. "The Critter" was mentioned as a popular sprayer.
We use the EZ sprayer for $25 from Archie Bray at about 25lbs pressure.
Marcia in Montana
Andi Runt wrote:
>
> ----------------------------Original message----------------------------
> Hi Clayarters,
> To any of you experienced in spraying glazes: I'd love a verbal
> crash-course in spraying, addressing such issues as - do you need to wax
> feet? Pour or spray insides of vases? several light coats or one-two
> heavier coats? Glaze consistency? Any other application / clean-up
> techniques / tips / tricks? I haven't been able to find someone to watch
> spraying, so maybe a verbal description would give me a jump on the
> learning curve. TIA (Addicted to Clayart - loved Joe Molinaro's article
> "Cyberclay" in latest CM)
> Andi in PA. where the petunias are still blooming at Halloween!
>
> Andi Runt
> Impressions in Pottery
> State College, PA
> jpri@email. psu.edu
Bill Hall on sun 1 nov 98
> To any of you experienced in spraying glazes: I'd love a verbal
> crash-course in spraying, addressing such issues as - do you
> need to wax
> feet?
I wax the feet for several reasons. I often use a combination of dipping and
spraying. When you spray close to the foot, especially on a bowl, some glaze
will get on the foot. Also, it makes a cleaner edge to the glaze. You can't
really spray a clean edge on the foot.
> Pour or spray insides of vases?
I do both depending on what I want to achieve. It's hard to spray all the
way to the bottom of a tall slender form, though. Sometimes I will pour
glaze on the inside of a piece, and then spray one or more glazes on top of
the inside glaze. Then I'll usually spray another glaze on the outside.
several light coats or one-two
> heavier coats?
I apply several light coats, but I do it continuously, rotating the piece on
a banding wheel or turntable. By the time you spray all the way around the
piece, it's dry enough for another coat, so I just continue to spray and
rotate. I usually move the sprayer slightly up and down to get more even
coverage. If you get too heavy a coat, the glaze will run.
Glaze consistency?
I use a Critter, and the same consistency used for dipping works just fine.
Any other application / clean-up
> techniques / tips / tricks?
Dipping or pouring is faster than spraying, so I only use spraying if I
can't do what I want otherwise. By spraying, you can apply areas of glaze
without a distinct edge on top of another glaze. You can get almost a
gradient effect, too, depending on how the two glazes interact.
Spraying is the easiest way that I have found to put a different glaze on
the inside than the outside of a piece, especially a bowl. Put the piece on
a banding wheel in your spray booth.
When you spray the inside, first direct the spray into the bottom of the
bowl, rotating it to evenly spread the glaze. As you gradually work your way
up the inside, lower the spray gun more to the side of the bowl such that
the spray goes over the top of the near side, but hits the far side. (Harder
to describe than to do.) This makes the spray hit the inside without getting
much glaze on the outside. You'll always get a little overspray on the
outside, but usually this isn't enough to ruin the effect.
When you're spraying the other glaze on the outside, spray from an angle
slightly underneath so that you don't get much glaze on the inside.
Most important tip: Wear a good respirator.
If you have more questions, perhaps we should continue offline.
Bill Hall
mailto:bill@applink.net
orion on sun 1 nov 98
Here are a few tips you might want to try with spraying glaze:
a) Make your own "low-boy" spraybooth turntable by screwing a scrap of
plywood (or an old bat!) to a "lazy susan" hardware base (these are
inexpensive -- between $8-15 US dollars at any hardware store). (I've
coated mine with wood-sealer for easy clean-up.) I think this sort of
turntable works much better than a banding wheel in the spray booth!
b) I suggest that you DO wax pot bottoms (feet) before spraying, or ELSE
place each piece on a terrycloth towel (or some other deep, nappy fabric
that can easily be rinsed & washed between uses).
c) I almost always place a lining of newsprint, paper towels, and/or
big-roll wrapping paper* on the spray booth work table and low-boy turntable
(keeping a sheet under the work being sprayed). Lining paper serves a
couple of purposes: quick and easy clean-up (particularly between color
changes); test target(s) for sprayer adjustments; for quick centering of
pots on the turntable -- etc.
Spraying and airbrushing will add a whole new dimension to the "wonderful
world of glazing." Enjoy!
Ellen Baker - Glacier, WA
orion@telcomplus.net
*individual restaurant sandwich-wrap sheets can be very handy around the
shop! (and they're thrifty) -- available through a restaurant supply
(wholesale prices)
Rob on mon 2 nov 98
Spraying is an easier and even way to apply most glazes. Pour the inside
of most all pots then spray the outside. I haven't found waxing
necessary, just wipe off what little glaze may be on the bottom. The
thickness is, unfortunately, dependent on the glaze itself. Typically
glazes that react a lot with the clay body for color would need a lighter
coat. This could be one or two coats. Other glazes need heavier
applications, you'll have to experiment. Oribe green for example is
considerably different poured vs sprayed. I use a cheap hand held garden
sprayer that's pumped up by hand and sprayed, it handles everything but
to coarsest ash glazes. There are certainly better things available if
you want to spend the money.
Cindy Morley on tue 3 nov 98
At 10:15 AM 11/2/98 , you wrote:
I use a cheap hand held garden
>sprayer that's pumped up by hand and sprayed, it handles everything but
>to coarsest ash glazes. There are certainly better things available if
>you want to spend the money.
Could you possibly explain this sprayer more? I don't have an air
compressor but would like to be able to spray my glazes, and this seems
like a possibility... Thanks
Cindy Morley
Fayetteville AR
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