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sawdust firings - long

updated wed 30 apr 97

 

Sylvia See on fri 11 apr 97

Hi Nancy;
I do alot of sawdust firings, and am not sure what you are looking for in
finished product. I do not get alot of pure black pots so will let someone
else suggest how to get the blacks. I like mine for the variations I get
from the fire. Here's what I do.
I have used the inside drum from and old dyer, placed in a hole in the
ground lined with cement blocks to hold the shape of the hole. It worked
really great and had the advantage of being able to lift it out of the hole
and remove and piece of tin from the bottom hole and setting it on top of a
metal garbage can to clean out the ashes. I made a lid for the top and
cracked it about 1/2 inch. I now use 2 old electric kilns I got for 50
bucks apiece and they are more portable.
I have used many different kinds of clay and each gives it's own effect. I
have burnished some and some not. I really like the burnished pieces the
best. Some I used terra sig, and they were the blackest. I burnish in the
leather hard stage and use my giffin grip to get a really hard shine.
I then bisque to cone 06. Any higher and you get lighter pots. After
bisque I brush on three thin coats of bluestone (get it from United Farmers
Assoc, or farm suppliers, its used for treating fence posts and water in
dugouts). You can also use soluble colorants which are a son-of-a-gun to
get, I got mine from the drugstore, special ordered and they cost a bundle.
Use a foam brush like you get from hardware stores, or makeup brushes from
hairdressers. and apply very thinly. Try not to let it run on the pots as
it almost eats into the clay and can spoil the pot. You can also do designs
with felt markers as wax resist, or sticky stamps, leaves, flowers, or
anything else your imagination wants to try. I wrap the flowers or leaves
with white tissue paper, about 2 sheets and tape together with masking
tape. be careful with the tape, not to tape to pot or it make a mark on the
pot.
Loading: I fill about 6 inches of sawdust on the bottom, set the pots,
which are filled with sawdust, in and sprinkle around the pots, red or blue
salt, vermiculate, and sawdust, then repeat, layer after layer, also adding
layers of pots and layers of sawdust. I do not mix the salt and vermiculate
in the sawdust. I sprinkle the salt, then the vermiculate on and around the
pots, then the sawdust. I find the salt and the vermiculate, do their own
little number on the pots over which I have no control, and I like it that
way.
When filled to the top, I use a couple of self starting charcoal
brickettes, and light them at the top. I usually wait until I get a pretty
good burn going before I start closing it up, I crack the lid about 1/4
inch at the top, and open the bottom peep hole on the bottom of the kiln,
(On the drum, I had air holes around the sides). When it is burning really
well, I close the lid, and just loosen the peeps so that a little air is
still getting in, you have to have some air for it to burn, but I have it
cut pretty small, I find air gets in around the lid and the holes where the
wires used to be. Mine slowly burns for several days, sometimes close to 4
or 5 days. This burns pretty darn hot. I have only ashes and vermiculate
left on the bottom. I've never used my pyrometer, to determine the temp,
and my think to do that one day, but I know I''ve tried to rush some
firings, out of sheer curiousity, and the pots were red hot.
I live in town, and so have neighbors to consider with the smoke, and
found the drum in the ground was the easiest to control the smoke from. I
used old blankets, soaked in water over the top, and you would hardly know
it was burning. The only reason I had to change was in the initial startup.
That's where it get the really bad smoke for about and hour, and our
neighbor built a pool right next to where I had my pit, so I filled it in.
The kilns are more flexible and also portable so you can go to raku and
sawdust parties. Little note: for $100 dollars a year, I buy a town license
to operate my studio, and since I pitfire in the kilns, they don't complain
at all as I'm doing my pottery that I have a license for. When it was in
the ground, I had many raised eyebrows.
Now comes the work: I finish my pieces with natural beeswax. You have to
be careful melting it, as you don't want a fire, you can't put it out. I
melt in a gravy boat, sitting in water, burner only on high enough to melt
the wax. I pour the melted wax in small tinfoil tart cups, and turnout when
it is hard. I wash the pots, and dry them. Then I heat them in my oven,
about 300 degrees, and wearing cloth oven mitts, I wax the inside by
dropping in small pieces of wax while hot, swirling around to coat the
inside evenly, pouring out excess, and then take a piece of wax made from
cups, and using the mitts, quickly rub the entire surface of the pot. I
stop as soon as it starts to cool or stops being shiny. The mitts get
really heavy full of wax, and get pretty darn hot on the hands. Wear a
headband, as I work up a pretty sweat waxing. I then let them sit to dry
and polish. Tons of work by hand, if you have a giffin grip, use it. When
cool and dry, I rewax with a good clear floor wax and repolish. This is
really alot of work, but I feel well worth it. I love my primitive pots and
have had real flowers growing in some of them for three years with no
problems of water marking furniture, although I tell customers I will not
quarantee them waterproof. Covering the ass so as to speak.
The pots wrapped in tissue are usually the blackest; cone 6 porcelain
gives a beautiful burnish, low fire clays are the dullest, Laguana B-Mix
burnishes well and gives a grey finish, nice and unusual, and I have had
some red clay pieces that looked like they were made from wood when
finished. Terra sigs that I used went black but had wonderful leaf
impressions like fossils on them.
You will probably get as many variations on this as the posts recieved,
but this is what I do.
Sylvia See Claresholm, Alberta sylviac@telusplanet.net

The golden years have come at last, I cannot see, I cannot pee,
I cannot chew, I cannot screw. My memory shrinks, my hearing stinks.
No sense of smell, I look like hell. My body drooping, got trouble pooping.
The golden years have come at last, The golden years can kiss my Ass.