Autumn Downey on wed 17 jan 01
On platters and wide bowls, I like the type of solid handle (not a loopy
strap) that is attached to the rim and functions as an extension of it.
But these seem to be very prone to cracking.
It may be because I wait to attach them until I have trimmed - I suppose
applying them very soon after throwing - and then trimming on a chuck might
catch the timing better. That's about all that I can think of doing
differently.
Thanks for any suggestions.
Autumn Downey
Yellowknife, NWT
Cindy Strnad on thu 18 jan 01
Hello, Autumn.
I guess I missed your original post, so forgive me if I'm replying to a
question you never asked . . . but, if you're trying to attach handles at a
late stage, to your platter rims, here are a few tips.
First, it's best to avoid this if possible. You can attach handles before
the base of the platter is ready to be trimmed, then recover the platter
with a thin bit of plastic until it's ripe for trimming. Then, when you
trim, throw a chuck--in this case, just a wide, low pad of clay--to trim the
platter on. Using this will allow you to trim without damaging your handles.
If you do find you need to attach handles (or anything else) to pieces which
are too dry, you can try a couple of things. First, wet the piece down a
bit. Dip it in water (the rim only) for maybe 20-30 seconds, and allow it to
sit, covered with plastic, for several minutes, then repeat as necessary.
If this isn't feasible, spray the area with vinegar (vinegar seems to wet
clay down more quickly), let it sit a while, repeat as needed. Or, if you're
feeling brave, just wet it down with vinegar and attach the handle. Groggy
clay will help this questionable process to have the best chances
possible.Vibrate the base of the handle against the wall of the pot until it
really grabs hold.
However you treat the pot before attaching the handles, there's only one way
to treat it afterward. Being careful not to bump the wet handle(s), wrap the
pot in a plastic bag. Use two or three layers of plastic. (Yes, plastic is
porous, and to different degrees depending upon the plastic.) For this,
you'll want light plastic because of the danger of deforming the soft
handles, so use plenty of bags.
Remove the piece after about a week. Depending on your clay, you may or may
not be comfortable at this point with letting the piece dry naturally. If
you get (small) cracks at the handle joins, spray them with vinegar and
smooth them over as many times as is necessary.
Cindy Strnad
Earthen Vessels Pottery
RR 1, Box 51
Custer, SD 57730
USA
earthenv@gwtc.net
http://www.earthenvesselssd.com
PERRY STEARNS on thu 18 jan 01
Placing ordinary Seran wrap around extended parts enables slower drying =
so the piece comes into a 'ready-to-bisque' state at the same rate all =
over. Works for me in Arizona where we do 'dry' like nobody else. At =
Pewabic (in MI) we used a wet-box for same-rate drying!
Janet Kaiser on thu 18 jan 01
Autumn -
I am sure you will get lots of advice on
attaching handles at a late stage, both in
person and from the archives
http://www.ceramics.org/clayart
But would hollow, thrown knobs be a solution to
your problem? Fit with your style and design of
bowl?
You could stick a pin through for the biscuit
firing, if you are nervous about the enclosed
space.
Just an alternative idea...
Janet Kaiser - BTW Autumn, your lovely name
would be "Medi" in Welsh.
The Chapel of Art . Capel Celfyddyd
HOME OF THE INTERNATIONAL POTTERS' PATH
Criccieth LL52 0EA, GB-Wales Tel: (01766) 523570
E-mail: postbox@the-coa.org.uk
WEBSITE: http://www.the-coa.org.uk
----- Original Message -----
> On platters and wide bowls, I like the type of
solid handle (not a loopy
> strap) that is attached to the rim and
functions as an extension of it.
> But these seem to be very prone to cracking.
Cat Jarosz on thu 18 jan 01
Hi Autumn .. you might try using your same clay body but with extra
grog added to it so it wont shrink as much as one way to avoid cracks ...
another is to form the handle and let it set up a bit before attaching ....
the combo of the 2 is really helpful.... some folks wax the handle after
so it wont dry as fast others cover it with plastic... I generally just
cover the whole thing with plastic and let the moisture even out and try to
leave it to dry really slowly under the plastic.. hard to do in winter
time but doable .... ergo I seem to work backwards making the big stuff
first so it has plenty of time to dry slowly and small stuff last as it
seems to be ok with flash drying... hope this helps some or at least
gives you some extra imfo to work with.... Cat Jarosz
Bobbi Bassett on fri 19 jan 01
In a message dated 01/17/2001 4:52:05 PM Eastern Standard Time,
downeya@INTERNORTH.COM writes:
> On platters and wide bowls, I like the type of solid handle (not a loopy
> strap) that is attached to the rim and functions as an extension of it.
> But these seem to be very prone to cracking.
>
Autumn,
Are you making handles that "hang over" the edge of the platter? If so
perhaps gravity is putting too much strain on the handle while it's drying. I
put a lot of handles on bowls and platters and use chunks of foam rubber
under the handle while it's drying. The foam gives with the shrinkage and
gives it just enough support.
Bobbi in PA
Autumn Downey on fri 19 jan 01
Hi Bobbi,
I don't think it's gravity. Probably just that I was attaching handles a
little too late. But if I did the handles earlier, I would have to watch
out for the drooping effect like you say.
I haven't been doing many this way, (because of success rate) but it seems
that once the handle is a little dry it won't bend any more to conform to
the shrinking plate. Strap handles, generally have worked better.
I had wondered if throwing the handle and putting some internal memorized
bend into it would make a difference. But, am thinking, in truth, that
it's just timing - not my best thing! Unless I work at it.
Also suffering from sluggishness (post holidays) and don't mind in the
least blaming the lack of light.
Autumn Downey
Yellowknife, NWT
>In a message dated 01/17/2001 4:52:05 PM Eastern Standard Time,
>Autumn,
>Are you making handles that "hang over" the edge of the platter? If so
>perhaps gravity is putting too much strain on the handle while it's drying. I
>put a lot of handles on bowls and platters and use chunks of foam rubber
>under the handle while it's drying. The foam gives with the shrinkage and
>gives it just enough support.
>
>Bobbi in PA
Martin Howard on sat 20 jan 01
Autumn, we had a long thread on rims on plates and why have them a little
while ago.
Ever since then I have thought that plates with rims are best done upside
down on a mould. Then gravity works against the mould.
The problem, described is several books, but I cannot think quite where at
the moment, is that we so often BEND and therefore stress the clay as we
fold up the side and then fold down the rim. I remember a diagram of just
how the clay platelets inside get in a right state and give up.
The solution given was the raising the side and throwing the rim should be
done as a natural movement, up and out all the time. So leave enough clay at
the top, leave the plate on the wheel to harden up a bit, then throw the
rim, rather than just bend it.
I know your problem is a little different, but the principle in the clay may
be similar.
Just turning it upside down to fix the handles, using the support of the
table top might be all you need.
Martin Howard
Webb's Cottage Pottery
Woolpits Road, Great Saling
BRAINTREE, Essex CM7 5DZ
England
martin@webbscottage.co.uk
Liz Willoughby on sun 21 jan 01
Autumn Downey said,
>On platters and wide bowls, I like the type of solid handle (not a loopy
>strap) that is attached to the rim and functions as an extension of it.
>But these seem to be very prone to cracking.
Hello Autumn,
A solution for you might be to throw bowls with a large rolled over
edge. I make a lot of bowls this way, and it gives you a nice
natural fat edge with lots of strength, and and no sharp edges that
can get knocked off or chipped. After the clay sets up, pin prick
the hole to let the air out to prevent a crack. Then leave it. Care
not to let glaze get in that hole when glazing or it will crack. A
tiny hole is all that is necessary, it will usually close up enough
in the bisque.
Liz
Liz Willoughby
RR 1
2903 Shelter Valley Rd.
Grafton, On.
Canada
K0K 2G0
e-mail lizwill@phc.igs.net
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