Dan Saultman on sat 26 jul 97
Hi Group,
I'm having a heck of a time with my handles, spouts etc. cracking at
their assembly points during drying. I have switched from a very
smooth clay body (B Mix) to one with a little more grog (called half &
half) and even to a rather groggy body (Dover sand by mile high) and
still the problem. I let the pots set for a day or so under plastic to
equalize their moisture, but as soon as I expose them to the drying
rack they start to crack at these junction points. I guess I could
wrap each handle in plastic and hope but THAT'S a lot of work. I used
to just finish them up and let em' dry. I've got some pretty fancy
pots that I'm afraid to open up to the air except for a few hours a
day. At this rate I'll never get a load done! Any ideas on what's
happening here?
Dan Saultman in overcast Colorado.
Autumn Downey on mon 28 jul 97
This may not be the answer to your particular drying problem, but it helped
with my wheel thrown pots.
In a small studio (during winter) where the heat was being turned up during
working hours and down over night and where drafts and air currents near
walls were different from the centre of the room, I was having trouble
getting things dried without cracking - or dried, period. Condensation
under the plastic added to the difficulties.
I wound up leaving things on tables in the centre of the room and draping
old cotton sheets over the work. If I felt it was going too fast, a plastic
sheet could be draped loosely over top as well. With monitoring, it was
possible to keep the drying moving along at a fairly constant rate.
The idea of using cloth to wick water away comes from an old Plainsman info
sheet by Luke Lindoe. I think it was suggested for drying large sculptures
under plastic, with a layer of absorbent cloth between the sculpture and the
plastic. The cloth was removed as it became damp and replaced with a dry one.
I suppose if your pieces won't support cloth touching them, some kind of a
tent could be tried. Hope this helps.
Autumn Downey
downeya@internorth.com
Yellowknife, NWT, Canada
Robert Speirs, M.D. 12 4450 on mon 28 jul 97
Boy, are you singing my song! For the past year I've been using
Laguna's ^5 B-mix and having a terrible time with the handles cracking
at the join. I have tried everything: using vinegar to join, using
paper clay to join, putting handles on when the pot is pretty wet,
drying under plastic for at least 5 days, drying it upside down so
there's no stress on the join, and the only thing I haven't done yet is
paint wax at the joining point. I usually get my cracking in the glaze
firing, however. This is such a bummer because I think I'm home free
if it looks OK after the bisque. I've almost stopped making anything
with handles because of this. I also have just bought a mid range
porcelain from Seattle Pottery to use for my pieces with handles. I
called Laguna for advice and also talked to them at NCECA about the
problem. They're at a loss and don't have any other ideas for me (so it
must be MY fault, not the clay's, right??).
I suggest you try all of the above tricks before giving up on the clay.
I just love how that B-mix throws, so that's why I'm not stopping using
it entirely. I think drying under plastic for only one day is not enough
with a temperamental clay.
Best of luck. I can REALLY relate.
Laura in Oregon
Carol Jackaway on tue 29 jul 97
Have you tried little supports for your handles while they are drying?
Alittle stirfoam cube directly under the handle can help support the handle
during drying, which in turn strenghtens it during repeat firing. Also try a
"dab" of glaze in the joint. It fuses during bisque firing.
Carol
CoilLady
Alyss Dorese on tue 29 jul 97
Robert Speirs, M.D. 12 4450 wrote:
>
> ----------------------------Original message----------------------------
> Boy, are you singing my song! For the past year I've been using
> Laguna's ^5 B-mix and having a terrible time with the handles cracking
> at the join. I have tried everything: using vinegar to join, using
> paper clay to join, putting handles on when the pot is pretty wet,
> drying under plastic for at least 5 days, drying it upside down so
> there's no stress on the join, and the only thing I haven't done yet is
> paint wax at the joining point. I usually get my cracking in the glaze
> firing, however. This is such a bummer because I think I'm home free
> if it looks OK after the bisque. I've almost stopped making anything
> with handles because of this. I also have just bought a mid range
> porcelain from Seattle Pottery to use for my pieces with handles. I
> called Laguna for advice and also talked to them at NCECA about the
> problem. They're at a loss and don't have any other ideas for me (so it
> must be MY fault, not the clay's, right??).
>
> I suggest you try all of the above tricks before giving up on the clay.
> I just love how that B-mix throws, so that's why I'm not stopping using
> it entirely. I think drying under plastic for only one day is not enough
> with a temperamental clay.
>
> Best of luck. I can REALLY relate.
>
> Laura in Oregon
I, too, love Laguna B-mix and have had problems with it only in the
summer. I live in Palm Springs. Summers hot and dry going up to 120
sometimes. I discontinue using B-mix in the summer for four months and
use it the rest of the year with no problem.
Alyss in Palm Springs
Don Jones on tue 29 jul 97
> I suggest you try all of the above tricks before giving up on the clay.
> I just love how that B-mix throws, so that's why I'm not stopping using
> it entirely. I think drying under plastic for only one day is not enough
> with a temperamental clay.
>
> Best of luck. I can REALLY relate.
>
> Laura in Oregon
Laura,
I think that ^5 Laguna B mix is bad news in drying. Try the Bmix with sand.
Don Jones
Brooks Burgess on wed 30 jul 97
At 08:52 AM 7/29/97 EDT, you wrote:
>----------------------------Original message----------------------------
>
>> I suggest you try all of the above tricks before giving up on the clay.
>> I just love how that B-mix throws, so that's why I'm not stopping using
>> it entirely. I think drying under plastic for only one day is not enough
>> with a temperamental clay.
>>
>> Best of luck. I can REALLY relate.
>
>>
>> Laura in Oregon
>
>Laura,
>I think that ^5 Laguna B mix is bad news in drying. Try the Bmix with sand.
>Don Jones
>
>ive never tried b-mix but to dry clay w/o cracking in general this is what
i do... sit pots on board.... cover loosely with plastic...leave a.c. on in
studio if you desire... flip plastic sheet over to reverse side as soon as
condensation occurs..continue until no more condensation... plastic may then
be left off... for large platters etc. cut hole in plastic so as to cover
rims not centers to promote even drying
hope this works for you
brooks
Claycuzian@aol.com on wed 30 jul 97
I have used B-mix from Laguna for several years and have had the same problem
in the past (cracking at the joined areas). The trick is to trim the piece
before the lip dries too much, and the top of the pot becomes too hard, AND
to use wax resist over the joined area. Finally, cover the pieces for a day.
If you cover your pieces lightly a couple hours after you throw them (flip
them at this time if you can), when they are too wet to trim, you can even
out the drying, trim the pieces the next day. This early covering of the
pieces will prevent the dry top and soggy foot syndrome. This should work...
you might try defloculating your slip by adding some sodium silicate as well.
Good luck, David Cuzick in San Diego, CA
Wilkinson on thu 31 jul 97
I know this has been mentioned before but not so regarding this latest
inquiry. Living in New Mexico where it is dry we have found that waxing
around a newly attached handle or appendage join has been a real lifesaver
for us since the pots always seem to be much dryer than the handles when
the two are joined. Waxing the join areas after they are joined gives
balance so to speak to the moisture between the two at the join. That
along with slow drying has solved the cracking at the handle thing for us.
Lori Wilkinson
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