Stauffer Linda on sat 26 jan 08
I have the same pug mill. You don't have to run the vacuum pump when
you pug clay, but I always use the Vac. pump to de-air the clay. You
must make sure that the cap is on the end of the pug mill or air will
be drawn in by the pump, the lid is sealed and the clean out door is
sealed. I usually wet the seal and press in on the door when starting
the pump. It goes to 22" Hg in no time.
Stauffer Linda
bkwrmkt@entermail.net
On Jan 26, 2008, at 8:52 PM, Sue Beach wrote:
Well, Ron & I got our new VPM9 set up today and started trying to
learn to
use it. We were doing pretty well for awhile and had run several
batches
of clay through the machine. Then it all stopped working for us. Since
we
are 100% new at using pugmills, we could use some advice.
So some questions:
Must the vacuum pump be running in order to pug clay? Ron says he
thinks
it should pug without the vacuum, but it sure isn't.
It seemed to get the 'spins' a lot. Suggestions?
The vacuum pump runs, but no pressure builds. We checked for leaks but
found none. Ron thinks the pump isn't working correctly. Suggestions?
We only pugged about 75 lbs of clay.
Any advice or helpful hints?
Thanks.
Sue Beach
Muncie, IN
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Sue Beach on sat 26 jan 08
Well, Ron & I got our new VPM9 set up today and started trying to learn to
use it. We were doing pretty well for awhile and had run several batches
of clay through the machine. Then it all stopped working for us. Since we
are 100% new at using pugmills, we could use some advice.
So some questions:
Must the vacuum pump be running in order to pug clay? Ron says he thinks
it should pug without the vacuum, but it sure isn't.
It seemed to get the 'spins' a lot. Suggestions?
The vacuum pump runs, but no pressure builds. We checked for leaks but
found none. Ron thinks the pump isn't working correctly. Suggestions?
We only pugged about 75 lbs of clay.
Any advice or helpful hints?
Thanks.
Sue Beach
Muncie, IN
William & Susan Schran User on sun 27 jan 08
On 1/26/08 8:52 PM, "Sue Beach" wrote:
> So some questions:
>
> Must the vacuum pump be running in order to pug clay? Ron says he thinks
> it should pug without the vacuum, but it sure isn't.
No, but they clay will not be de-aired.
>
> It seemed to get the 'spins' a lot. Suggestions?
This is normal - the "spins" or "spinnies" - clay is too wet. Add some drier
clay or dry powder clay. Takes a while to get used to this and make
corrections.
>
> The vacuum pump runs, but no pressure builds. We checked for leaks but
> found none. Ron thinks the pump isn't working correctly. Suggestions?
We use a VPM 20 and find the 99% of the time the little loose metal plate
(the one with the "warning" on it) is the culprit. Gave a wipe with damp
sponge along the gasket and the metal edge of the machine, making sure both
are clean, and when you switch on the vacuum pump, hold the plate against
the mixer body with a bit of pressure. When the vacuum begins to rise, you
can let go of the plate.
Also make sure to wipe clean the gasket on the hopper lid and top hopper
edge for a good seal.
>
> We only pugged about 75 lbs of clay.
OK, that's 3 loads in the machine
>
> Any advice or helpful hints?
Read through the instruction manual again, then read it again, then read it
while to mix/pug the next batch of clay.
Just like a new car, gotta learn how it works.
Bill
--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com
Carl Finch on sun 27 jan 08
At 05:52 PM 1/26/2008, Sue Beach wrote:
>So some questions:
>
>Must the vacuum pump be running in order to pug clay? Ron says he thinks
>it should pug without the vacuum, but it sure isn't.
>
>It seemed to get the 'spins' a lot. Suggestions?
>
>The vacuum pump runs, but no pressure builds. We checked for leaks but
>found none. Ron thinks the pump isn't working correctly. Suggestions?
>
>Any advice or helpful hints?
This was discussed not long ago. Search the Archives for "spinnies."
Here's one of the five messages I found within the last year or so:
========begin quote========
From: Bruce Girrell
Date: Mon, 23 Oct 2006 10:47:49 -0400
Subject: Re: pugmill, learning curve
Peter Pugger questions:
> How full is full?
Probably one of the tougher questions. I run mine a little on the full side.
It seems to work better for me that way. YMMV. I have a VPM-30, which means
that PP rates the machine for 30 pound loads. If I start with all dry clay,
I use 35 pounds of dry clay and a gallon of water. That produces 23% water
content. It takes only half a cup more water to make 24% water content,
which results in a very different feel of the clay. Pay close attention to
your water content.
> Does it have to run full?
No, but I find that the machine does not seem to pug as effectively when it
is not full. I always try to run it full.
> How long should you let it mix for a homogenous load?
That depends on what you put in it to start. Dry clay powder and water (the
optimal mix) could be homogeneous in 15 min. Other combinations will take
longer. Leather hard scraps may take just this side of eternity.
> I seem to get many loads that just spin, so I keep adding clay
> and eventually get it to catch, but would like to know how to
> add clay and in what combination of consistencies to prevent
> this in the first place.
Ah, the spinnies. The curse of PP owners. Next mixer/pugger I get will be a
double auger model.
The culprit here is water. If you add water or slip too quickly it will form
a lubricating film around the inner surface of the mixing chamber and the
result is the infamous spinnies.
Some tips:
1) Whenever possible, use dry clay and water as your starting point. Not
only will you minimize spinnies, but you will also produce a more consistent
water content in your result.
2) Add water slowly. Add some water, mix, stop, add some water, mix, stop,
...
Working this way at least allows you to regain control fairly quickly should
you get a case of the spinnies.
3) Add water at the nozzle end of the mixing chamber, not the motor end.
If you add water at the motor end, the water can be pushed through the clay
excluder into the vacuum chamber and not end up in your clay, resulting in a
stiffer result than you expected. As I noted above, only 1/2 cup of water
makes a 1% difference in water content. And it takes only a couple percent
difference in water content to be the difference between too soft and too
hard.
4) Check your vacuum chamber after each load and clean it if necessary. It
doesn't have to be sparkling, but there shouldn't be clay piled up to the
shaft or a puddle of water there either. The presence of some clay and/or
water is normal
5) Listen to the sounds that you machine makes. You will learn to recognize
the sound of it working too hard (clay too dry). You can tell if you have a
case of spinnies just from the sound. The machine talks to you. Listen. Yes,
it's voice is a bit abrasive and loud like Aunt Ethel, but put some cotton
in your ears and listen to what it is saying.
6) As noted in a different post that I made under this same thread, prior to
deairing the batch you must be certain that air can move from the mixing
chamber to the vacuum chamber. The easiest way to do this is to run the
vacuum up to 20 inches or more and then set the machine to pug mode while
feeling the end cap to be sure that you don't actually start pushing clay
out. Within a couple of seconds you will probably hear a sudden change in
the sound and see a sudden drop in vacuum. Stop the machine and wait for the
vacuum to be re-established. Once you get a good vacuum, put the machine in
mix mode to accomplish the de-airing.
7) I keep a 1 1/4" wooden dowel around (tapered to a blunt point at one end)
to help move clay around inside the mixing chamber. A tougher material would
be better (because the wood sometimes splinters off, leaving wood hunks in
the clay) but I do OK with the dowel. I use the dowel a lot if I get a bad
case of spinnies. I push clay away from the motor end toward the nozzle end.
I also use the dowel to poke holes in the clay so that I can add water into
already moist, but not quite soft enough, clay. Adding water in a number of
small holes helps avoid the spinnies.
8) The people at PP have been extremely helpful regarding any problem that I
have had. I hear the same from others. They have sent me detailed drawings,
they have spent lots of time on the phone with me and they have even sent
parts for free when they didn't really have to (a part that made the machine
run better, but that didn't affect its safety, for instance). Call them when
you need help. They really do try to do a very good job.
Also, I have a bunch of photos showing the complete teardown and rebuild of
a VPM 30, but I have never put them together as a document. Some changes
have been made to the design since my machine was built so now I don't know
how applicable the photos are, but they should still be fairly
representative.
> I am reclaiming clay that is both too hard to use and absolute mush.
> Should I stick to one variety per load?
You can mix dry clay with mush and you can mix dry clay with water. But
never mix overly hard clay with mush or water. You will end up with hard
lumps in your mixed clay.
Overly hard clay can be mixed with dry, but it doesn't seem right doing that
to the machine. The best thing to do with clay that has gotten too hard is
to let it dry completely. Break up large chunks of dry clay before putting
them into the mixer.
Bruce Girrell
===========end quote========
--Carl
in Medford, Oregon
Doric T. Jemison-Ball ll on sun 27 jan 08
Dear Ron and Sue:
I'm not familiar with the VPM9 but I have a VPM20, the next size up.
It pugs fine without using the vacuum feature.
What you seem to be describing is a case of the "spinnies" - you're clay is
too wet and sticky and is just spinning inside. This also is exacerbated if
you overload it a bit with too wet clay.
Some solutions:
1. Try taking out some of the clay and replacing it with dryer clay
2. Just try taking out some of the clay if you don't have any dryer clay and
use a wooden or plastic tool to push the clay down to the bottom and away
from the blades. If your VPM9 has a mixer function like the VPM20, switch it
to mix, then try pugging again after it has mixed a bit if you haven't
developed the spinnies again..
3. If all else fails, overload it to the max, mix and then PUG.
There is a too wet limit where you'll get the spinnies. Try and get a better
balance of wet/dry so that the resulting mixture isn't too wet.
4. If you've pugged 75 lbs, try refeeding the clay you've pugged back into
the too wet spinnie mix to get a dryer average mix.
Doric T.Jemison-Ball II
BBS-LA
14622 Ventura Blvd. #727
Sherman Oaks, CA 91403
707-884-5067 Voice
707-884-4449 FAX
818-606-6678 CELL
buffalo@bbs-la.com
http://www.bbs-la.com
"You can always cure the sausage that's too long"
Susan Gatherers
----- Original Message -----
From: "Sue Beach"
To:
Sent: Saturday, January 26, 2008 5:52 PM
Subject: Questions for Peter Pugger users
> Well, Ron & I got our new VPM9 set up today and started trying to learn to
> use it. We were doing pretty well for awhile and had run several batches
> of clay through the machine. Then it all stopped working for us. Since we
> are 100% new at using pugmills, we could use some advice.
>
> So some questions:
>
> Must the vacuum pump be running in order to pug clay? Ron says he thinks
> it should pug without the vacuum, but it sure isn't.
>
> It seemed to get the 'spins' a lot. Suggestions?
>
> The vacuum pump runs, but no pressure builds. We checked for leaks but
> found none. Ron thinks the pump isn't working correctly. Suggestions?
>
> We only pugged about 75 lbs of clay.
>
> Any advice or helpful hints?
>
> Thanks.
>
> Sue Beach
> Muncie, IN
>
> ______________________________________________________________________________
> Clayart members may send postings to: clayart@lsv.ceramics.org
>
> You may look at the archives for the list, post messages, change your
> subscription settings or unsubscribe/leave the list here:
> http://www.acers.org/cic/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots2@visi.com
>
Sally Guger on sun 27 jan 08
Sue Beach wrote:
Must the vacuum pump be running in order to pug clay?
It seemed to get the 'spins' a lot. Suggestions?
The vacuum pump runs, but no pressure builds. We checked for leaks but
found none. Ron thinks the pump isn't working correctly. Suggestions?
Here's my slant on this:
I have 2 of the VPM20's and I used to "baby" them. I'd try to get a certain size batch- spend a lot of time cleaning the rubber seal to be able to vacuum the batch, etc. Then a master potter (Don Hunt in case any of you know him) came to work with my students for 2 days-and we went through all of my buckets of re-claim in about an hour.about an hour.
This is what now works for me.
I just keep feeding it more clay and keep it on PUG. If what comes through isn't perfect, I just throw it in again. Once enough clay is hanging out around the edges, it will vacuum seal without getting it all clean. The "spins" are typical if you've added slip or water. I take a ball of about a pound or two of firmer clay- not rock-hard but firmer than you can throw with- and put it on top of the spinning mass. When the lid shuts down, the ball of clay usually dislodges the wetter stuff from the blades and sends it on its way.
I don't de-air the clay my students use. When they are finished on the wheel-they just put back all of their goof-ups. The slip and throwing water gets but in a bucket and spread out for a day before it gets pugged. Totally dry stuff gets soaked in water- Sometimes we sprinkle a cupful of powdered clay on the top but not usually-I like to keep the dust to a minimum.
If this sounds like a lot of work, it isn't. This is with at least 50 novice potters using the studio. If I want more perfect clay, I do put it on "MIX" for a while-and also vacuum it. But it should for sure send out pugged clay without the pump on. The clay is really decent and just needs a little wedging if it isn't de-aired. When it's been de-aired it's as dense and perfect as what comes in bags from clay companies.
However, it can be tricky to get pressure to build up sometimes. Check the rounded rectangle of a front plate- and take it off and slam it up against the gasket- maybe yours isn't just like the bigger ones- I don't know. Also, just make sure the top lid is clamped tight and the seal is very clean- (until it starts working by sealing itself against the layer of clay.)
Also, I just close the hopper and make sure the end cap is on and leave it all summer!
I love this machine. I still say it's different and better than anything else out there. They do have the patent on de-airing the entire chamber from what I was told. Also, the tech guys from Petterpugger will spend as much time as you need on the phone with you and walk you through it if necessary. Hope this helps! Sally
Live, Give, Love
Beyond All Expectation.
Sally Guger
Lakespur Blue Pottery & Sculpture
Lodi, Wisconsin, USA
http://www.saukpr.k12.wi.us/~gugersa/the_art_teachers.htm
---------------------------------
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Lynne and Bruce Girrell on sun 27 jan 08
Sue Beach wrote
> We were doing pretty well for awhile and had run several batches
> of clay through the machine. Then it all stopped working for us.
> Must the vacuum pump be running in order to pug clay?
It's not necessary to have the pump running during pugging. I usually do
leave it on, at least at the beginning of pugging, but as long as the vacuum
is maintained, you're OK.
> It seemed to get the 'spins' a lot. Suggestions?
Ah, the spinnies. The bane of PP users.
Excess water is the problem. If you are adding water to already wet clay, do
it in very small quantities and do it on the left (nozzle) end of the
chamber. I have a VPM30 and when I add water to already wet clay, I add no
more than about a cup at a time. Since a cup of water increases the water
content of the batch by about 1% it's also convenient that way as well. For
a VPM9 you would want to scale down by an appropriate amount. Maybe you
could add as much as 1/2 cup at a time.
Always add the water on the nozzle side of the mixing chamber. That way, the
water is more thoroughly mixed. The clay is dragged from left to right
(nozzle end toward vacuum end) through the machine during mixing.
When mixing from dry powder, I add the required amount of water first, then
slowly add the clay powder. I find that you will lose less through the
vacuum port that way. I seem to lose more water into the vacuum chamber if I
add the powder first. Get the mix as close to the desired water percentage*
as you can in the initial mix. Adding water later has to be done slowly.
If you get stuck with a case of the spinnies, there are three approaches.
1) Go do something else for a day or so. The excess water will slowly get
taken up by the clay and resolve the problem.
2) Add dry clay powder. A quick fix, but now your total water percentage
will change and you'll have to add some water later.
3) Get a 1 1/4 - 1 1/2 inch wooden dowel (round one end) or a piece of PVC
pipe with a cap on the end. Turn the machine off, open the hopper door and
start mashing clay around. It can be a lot of work, and it may take a couple
of tries, but you'll get it going again in fairly short order. This is the
method that I usually use. Don't beat the dowel up too much or you can get
wood splinters in your clay.
> The vacuum pump runs, but no pressure builds. We checked for leaks but
> found none.
If the vacuum pump worked initially, it is very unlikely to have failed. I
suspect the plate that covers your vacuum chamber. The second suspect is the
hopper door. But I think the new PP machines use an O-ring on the hopper
door, so that is much less likely than on my machine, which has a gasket.
Inspect the area where the hopper door seals against the mixing chamber and
also where the vacuum port cover goes for any signs of clay residue. Clean
the rubber components with fresh water. Leave them wet. Sometimes I even
press my knee against the vacuum port cover when I turn the vacuum pump on.
Another possiblility, as experienced by another Clayarter recently, is a
plugged vacuum hose. In her case, mud dauber wasps were the culprit but I
doubt that yours is old enough to have critter problems. However, check for
kinks in the hose or debris at the opening into the vacuum chamber.
By the way, the gauge is reading "inches of vacuum". There is no pressure
buildup. Air pressure at sea level is about 30 inches of mercury. The gauge
is telling you how many of those inches you have removed. So when the gauge
reads 25, you have removed 25 of the 30 inches, leaving a pressure in the
chamber of 5 inches of mercury. That's a good enough vacuum for our
purposes.
If you continue to have problems, call Peter Pugger. They have always been
extremely helpful for me and I believe that others on the list have had
similar experience. We can debate the design principles of the machine, but
their customer service has been some of the best that I have ever
experienced.
Good luck,
Bruce Girrell
*If you don't know what your ideal water percentage is, do the following:
1) Get some clay that is already the proper consistency. That is, get a
sample of clay that throws well.
2) Put a small amount (maybe 4 inches square) of aluminum foil on your scale
and set the tare so that the scale reads zero.
3) Weigh out 100 grams of the clay sample.
4) Flatten the clay so that it will dry more easily. Make sure that it still
weighs 100 grams
5) Dry the clay sample _completely_. I usually bake the clay sample in a
toaster oven. Be sure that you don't heat it too quicky, though, as it will
have little mini explosions, spitting clay all over, which will require you
to start all over
6) Weigh the clay again
7) Water percentage = (Wet weight - Dry weight)/(Dry weight) x 100
Lynne and Bruce Girrell on sun 27 jan 08
And another thing -
Either reclaim your clay while it is still moist enough to be mashed around
or else dry it completely before reclaiming.
The very, very worst thing you can do is try to reclaim leather hard clay.
It just won't mix properly and you will end up with hard lumps in your clay.
Encountering a lump while throwing is disastrous. There is almost no way to
rescue a piece with a hard lump. I throw thin. Maybe in a thick walled piece
you could dig out the lump but, hey, just don't try to reclaim leather hard
clay.
Bruce Girrell
Ivor and Olive Lewis on mon 28 jan 08
Dear Sue Beach,=20
You ask <>
For several years I had access to an early Venco Pugmill. It produced =
well blended uniform clay without the need for a vacuum pump. To get the =
best effect my students would put the clay through three times. But it =
seems to me to be a waste of financial resources to purchase a mill with =
a vacuum pump and not take advantage of the facility.
I continue to ask if a de-airing pugmill removes only air or does it =
extract other substances. It seems as though no one has published =
analyses of the exhaust from these machines. Could it be that, at the =
optimum reduction in pressure below atmospheric, water would evaporate =
rapidly. This might account for claims for superior throwing properties =
from Vac Deaired Clay.
Have fun with your machine.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
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