Heidi Haugen on sun 11 feb 01
Thanks to all who helped me last month with my plethora of venco pug
wiring questions. They definitely need a more detailed manual, just not
much to work with. We got the beast running today..big smiles here. My
clay/slop was much too wet. (knew it but couldn't contain myself)
anyhow.. blew some nice blotches all over the place and into the pump
hose. (cleaned up pretty well, don't think I did any damage)
My query now lies in the slop/clay/waste prep before pugging. Do most
of you puggers leave it in the bucket until it's dry enough to form into
balls for the mill or do you speed the process through other means? i.e.
drying on cement or canvas. My initial thought was that I would mix in
ball clay or just dry pre-mix clay (I use archie bray abf oxidation).
when I called the bray, i was told i didn't need any dry material to mix
in so I'm just curious what you all do before pugging.
thanks in advance,
Heidi Haugen in western Montana, dreading cleaning the chimney in the
morning amidst all the snow and still cleaning up from the pug bomb that
went off in my studio:) (can't help being one of those people who dive
in first and check for water later)
Ceramic Design Group on mon 12 feb 01
>
> My query now lies in the slop/clay/waste prep before pugging. Do most
> of you puggers leave it in the bucket until it's dry enough to form into
> balls for the mill or do you speed the process through other means? i.e.
> drying on cement or canvas. My initial thought was that I would mix in
> ball clay or just dry pre-mix clay (I use archie bray abf oxidation).
> when I called the bray, i was told i didn't need any dry material to mix
> in so I'm just curious what you all do before pugging.
While it may be true that you can pass clay in many different consistencies
though a pug mill, understand that these machines work best when using clay
that is perhaps near throwing consistency. Adding dry materials into the pug
to "set up" overly wet clay will cause a moisture differential throughout
the pug. If the clay is really soft and sloppy, you could run the risk of it
being sucked into the vacuum system and compromising the pump.
Its a simple matter of letting the overly wet slop dry out on your wedging
table or on plaster batts that you make specifically for this. Years ago we
made several large plaster tubs with heat tapes cast into them. We would put
the days slop into these tubs over night, plug them in, and in the morning,
the clay would be nicely set up and ready to run through the pug mill.
If you have a clay mixer such as a Soldner, just put all the slop into the
tub and add some dry mix to set it up. Make sure to let it age well as this
too will create a moisture differential and if the clay is used right from
the mixer, it will be, more than likely quite short.
For those technically inclined, these moisture differentials result from the
the new clay particles being insufficiently surrounded by water, also known
as the "water hull" concept. Dr. Lawrence has quite a thorough explanation
of this in "Ceramic Science for the Potter."
As I am sure some on the list know, the best way to make the best plastic
clay is to blunge it as a slip, screen it through a Sweco or similar
screening device, then dewatering the slip to the correct moisture content
by a filter press, and finally pugging the resulting cakes.
Best
Jonathan
Jonathan Kaplan, president
Ceramic Design Group
PO Box 775112
Steamboat Springs CO 80477
voice and fax 970 879-9139
jdkaplan@cmn.net
info@ceramicdesigngroup.net
Plant Location:
1280 13th Street Unit 13
Steamboat Springs CO 80487
(please use this address for all deliveries via UPS, common carrier, Fed Ex,
etc.)
"Custom design and manufacturing for the ceramic arts, giftware and pottery
industries. Molds, models, and tooling for slip casting, jiggering and
hydraulic pressing. Consultation on technical issues such as clay bodies
glazes, and kilns."
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