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taylor, burnishing, terra sig and all

updated sat 22 oct 05

 

Allyson May on fri 21 oct 05


I do a lot of burnishing for Naked Raku, horsehair, saggar, and pit =
firing. A grogged clay does not lend itself to the dry burnishing =
method very well. You get grog bumps which sometimes crumble and leave =
little pieces of grit behind which will scratch the burnished surface as =
you continue. These scratches are usually not able to be repaired. The =
grog bumps will be visible after firing. Sanding only increases all of =
these problems. A few coats of terra sig will take care of your grogged =
clay. I have never had any luck with burnishing terra sig so I just =
buff it well with a chamois or nylon pantyhose. This gives a more =
satiny finish than dry burnishing. I have found that Miller 10T EM 103 =
from Laguna is a wonderful clay for all types of alternative firings. =
It is very smooth and polishes like a dream. It is not as plastic as =
some clays in the throwing process but it is still very nice. It fires =
very white and takes smoke well. I also use a Laguna ^6 porcelain for =
much of my work but I like to live on the edge!! As far as the =
burnishing goes, I also dry burnish but with a variation of what is in =
the Watkins's book. At bone dry, I lightly sand my piece with 000 steel =
wool (great care is taken in the throwing to make sure the piece is =
smooth so sanding is at a minimum). Using a soft brush I remove the =
sanding dust. I then use pieces cut from an old t-shirt (no ribs or =
seams) ,wet them, ring them out partially and begin rubbing the piece in =
a circular motion. This gets rid of any scratches left from the =
sanding. I go over the piece 2-3 times rewetting the cloth as =
necessary. (Watkins tells you to use baby oil first. I tried it and I =
still think my way works better.) I then rewet the cloth, fold it over =
to make a smooth pad and work around the pot going from foot to lip in =
straight lines. This is the direction in which I burnish and I have =
found this is helpful in getting a smooth surface. I continue going =
over the pot and rewetting the cloth until the pot does not =
automatically begin to dry out. The clay will remain darker than when =
dry and not show spots of dry. Immediately, I rub copious amounts of =
baby oil into the pots surface. The pot is then set aside to dry a =
little. You will know when to burnish when you see areas of gray appear =
on the surface as the oil dries. If you burnish too early it will be =
streaky and you have to go over it again as it dries more. Burnish the =
most delicate or difficult areas first and then move on to large areas. =
The pot will remain workable a good amount of time if you don't work in =
the sun, next to a heater, or next to your firing kiln. If areas do dry =
out rub a little more oil on a small spot, let dry a little and =
continue. The patchy look will disappear as the pot dries. Don't =
handle burnished areas with your bare hands until after the final =
firing. Fingerprints show and can't be removed. Most metal objects =
will leave gray/black streaks as you burnish. These are permanent and =
ugly. I use polished stone agates of various sizes and shapes. Some =
stones work better than others so you need to experiment. Don't use =
hematite. It polishes like a dream but it is also known as Blood Stone =
and will leave pinkish red streaks on your pots after firing. I have =
the pots to prove this one! The pots need to dry out again before you =
bisque them. I usually bisque to ^ 010 and have gone as high as ^08 =
without a loss of shine. I think ^010 allows for the best absorption of =
smoke and color and gives a little more strength than ^012. This is =
probably way more info than you wanted but, you asked! I hope it helps =
in your quest. BTW, I am a displaced Texan! I grew up in Huffman, =
Texas. Good luck finding that one on your map! We lived on my =
grandfathers cattle ranch which made up most of the town at the time.
Peace,
Allyson May
Stoney Creek Pottery
Bloomington, IN 47408
AMay4@msn.com