Ivor and Olive Lewis on thu 5 oct 06
Dear Kath in Glasgow,
Your remark about aching arms after spending so much time pulling the =
handle down on that pug mill prompted my concern.
When I was teaching I had on loan an old Venco Pugmill. When I started =
to use it I was amazed that after putting clay in the hopper I had to =
use a lot of force to get the clay to emerge from the nozzle. So I did =
an inspection and found that the arm which actuated the plunger was =
bent, as though excessive force had been used to get it to work. In =
other words the machinery had not been treated as the maker intended.
So I stripped the machine down and inspected its parts. It seemed to me =
that the screw flights of the auger below the input opening were =
misaligned so that they were in fact driving the clay in the reverse =
direction, not forward to the orifice. I adjusted them to an angle that =
seemed appropriate, reassembled the machine and started feeding clay =
into it with the auger turning.
Wonderful result. Never again for the next ten years did we ever need to =
forcefully use the plunger to get clay to enter the chamber, just enough =
effort to get it to go past the safety grill.
Now I am not saying you machine is misbehaving and not working to =
specification. But it may pay you to inspect it and possibly seek advice =
if you have to put so much effort into the job.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
MoKa on thu 5 oct 06
Ivor
Thanks for your advice. It is a pugmill in a community group owned worksho=
p
and has indeed been subject to abuse over the years. The handle, too, is
bent from previous misuse. Last night was our first time using it after a
year and a half of it sitting abandoned because (a) No-one knew how to use
it and (b) the last person to use it left it choked with clay (or possibly
some other substance that had seriously impeded the inner workings).
We have spent the last several weeks (with only 2 hours a night once a week
access to the facilities!) meticulously cleaning it out and greasing the
moving parts to get it working again. I guess last night being our first
time using it after such an overhaul, it took some time to get going. It
did certainly get easier as the night went on, and we all had a very
rewarding experience at the end of it with a lovely neat pile of perfectly
pugged recycled clay.
We are now working on =8Creclaiming=B9 the rest of our equipment from the
neglect that it=B9s seen in recent years and intend to post full operating AN=
D
CLEANING instructions on laminated cards next to each piece of equipment.
We=B9re on a mission to have a fully functional working pottery workshop tha=
t
will benefit everyone (including ourselves) for years to come, so a few
aching muscles along the way will certainly be worth it.
Thanks again for your tips. If we do have any further problems with it,
I=B9ll certainly be back on the archives searching for your email.
Kind Regards
Kath, Glasgow
On 5/10/06 07:54, "Ivor and Olive Lewis" wrote:
> Dear Kath in Glasgow,
> Your remark about aching arms after spending so much time pulling the han=
dle
> down on that pug mill prompted my concern.
> When I was teaching I had on loan an old Venco Pugmill. When I started to=
use
> it I was amazed that after putting clay in the hopper I had to use a lot =
of
> force to get the clay to emerge from the nozzle. So I did an inspection a=
nd
> found that the arm which actuated the plunger was bent, as though excessi=
ve
> force had been used to get it to work. In other words the machinery had n=
ot
> been treated as the maker intended.
> So I stripped the machine down and inspected its parts. It seemed to me t=
hat
> the screw flights of the auger below the input opening were misaligned so=
that
> they were in fact driving the clay in the reverse direction, not forward =
to
> the orifice. I adjusted them to an angle that seemed appropriate, reassem=
bled
> the machine and started feeding clay into it with the auger turning.
> Wonderful result. Never again for the next ten years did we ever need to
> forcefully use the plunger to get clay to enter the chamber, just enough
> effort to get it to go past the safety grill.
> Now I am not saying you machine is misbehaving and not working to
> specification. But it may pay you to inspect it and possibly seek advice =
if
> you have to put so much effort into the job.
> Best regards,
> Ivor Lewis.
> Redhill,
> South Australia.
>=20
Bonnie Staffel on fri 6 oct 06
I have a very old Bluebird extruding pug mills. I go by the rule of not
forcing the clay. I let the plunger tell me what it wants to do with =
just
gentle nudging from me. In this way when I am running firmer clay or =
wetter
clay, there is a difference in resistance. Also the "spider" gasket or
whatever it is called will wear out with excessive pressure, IMO. XXX
fingers, but I have only changed that part once since the early 70's by
following this practice. I don't have anyone available to fix things =
that
go wrong in my studio so I take a lot of care of my machinery. I am =
able to
realign my slab roller myself and call on a dear friend to reinstall
elements in my kiln. But I don't want to wear out my friends so do
everything I can to prevent damage. Even my wheel was making funny =
noises
and with difficulty got my hand under the wheel head with fingers on the
shaft (turned off, of course) and felt that there were black hairs wound
around the spindle. The culprit or source would be from our family dog =
who
has a beautiful coat of hair and comes to my studio to visit once in a
while. Someone suggested that I burn the hair off, so that is what I =
do.
Takes just a few seconds with my propane torch. =20
Warm regards,
Bonnie Staffel
http://webpages.charter.net/bstaffel/
http://vasefinder.com/bstaffelgallery1.html
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