Sawdust in my kiln?

[shawnhar]

I just saw an amazing piece done by Michael Winser and he said he got the color by putting sawdust in the kiln so the piece became saturated with carbon from the sawdust smoke.  How do you think this is done, a sagar? The kiln bricks are not black. Said he is using low fire clay, maybe a big metal bucket?

 

 

[Marcia Selsor]

you can do it with a metal tine and 6 layers of toilet paper around the piece. Match the size of the can to fit the piece if possible. Bisque the piece to Cone 08. Don't fire much hotter than 950F.

 

[PeterH]

Found on p5 of https://ceramicartsnetwork.org/wp-content/uploads/2012/08/CA17D_Sample.pdf

Often, however, it is best to isolate the clay from the fuel so the smoke can reach all parts of the pot and there is no danger that unburned fuel will blanket some part of the pot and keep it from becoming black. Michael Wisner has developed two ways to accomplish this. To fire outside, he stacks pots on firing stands over sawdust, then covers the stack with a barrel. He builds a fire around the barrel, to create enough heat to cause the sawdust inside to smoke. Alternatively, he can stack pots the same way inside a gas kiln, using a metal barrel as a saggar.  I wrap pots in newspaper and then in tin foil, and fire in a kiln just until the newspaper smokes, which I refer to as a “modified saggar firing".

Trickiest of all is a silvery black surface. This can be encouraged by firing with damp fuel, so Judd sometimes dampens some of the manure in her saggar. If the silvery surface develops, it’s great; if not, the pots are still a rich, deep black. Wisner’s secret to the coveted silvery color is to burnish with graphite.  

 

 

[oldlady]

shawnhar, he piled the sawdust on a shelf.   look at the video at the bottom of the photo you posted.

[LinR]

Marcia are you saying that one firing will do?  In sawdust firing that I have had a chance to do previously we bisque fired to 018 first and then fired the pots in the sawdust kiln.  If one firing is enough I would be able to do it in my own kiln. Lin

[shawnhar]

Awesome thanks everyone!

I really want to try this, my biggest concern would be the smoke. My wife would kick my butt if I filled the house with smoke, lol.

Also wondering if the process requires low fire and green pieces. I would be interested in trying it with unglazed pots that have already been fired to cone 6.  

[Mark C.]

14 minutes ago, shawnhar said:

Awesome thanks everyone!

I really want to try this, my biggest concern would be the smoke. My wife would kick my butt if I filled the house with smoke, lol.

Also wondering if the process requires low fire and green pieces. I would be interested in trying it with unglazed pots that have already been fired to cone 6.  

better fire when she is away

[LinR]

Shawnhar if you sawdust fire with pots that have been bisqued at the usual temps you loose the burnished surface, that is if you burnished them.  We bisque fired our burnished pieces to 018  and then smoke fired and the low bisque retained the burnish.  Lin

[liambesaw]

Cone 6 would be vitrified, not able to take up carbon permenantly.  The 08 low firing allows carbon to deposit into the clay.

[shawnhar]

Thanks!

[Benzine]

On 3/12/2021 at 7:13 PM, shawnhar said:

Awesome thanks everyone!

I really want to try this, my biggest concern would be the smoke. My wife would kick my butt if I filled the house with smoke, lol.

Also wondering if the process requires low fire and green pieces. I would be interested in trying it with unglazed pots that have already been fired to cone 6.  

I regularly fire student's sculptural projects with crumbled newspaper in them.  We use the paper for support and to help the clay dry.  If we can't get the paper out before loading, it just stays in there.  I've had light, but noticeable smoke coming out of the kiln on several occasions.  There is a smoke detector fairly near the kiln, and it has never set it off.  Now the Chemistry and Food Classrooms on the other hand, they've set the alarms off multiple times!