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I am pretty excited.....I have been firing electric cone 6 for 5 years and my clay guy invited me to put some pieces on a shelf for a wood firing in September!   I have some cone 10 clay.  He said I can use his slips and glazes.  What else do I need to know?? 

 

Roberta

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Guest JBaymore

Ask some questions. 

 

What exactly is the TYPE of wood fired kiln and the length of the firing cycle?  What is the target end point cone in the hottest and coldest portions?  That info can dictate the approaches that would be most appropriate.

 

Typical Types

 

Anagama  (slightly sloping single tube chamber)

 

Dragon Kiln  (like anagama but narrower and longer)

 

Noborgama (chambered hill climbing kiln)

 

Train Kiln (variation on the anagama/dragon with elevated downdraft firebox)

 

Catenary arch single chamber crossdraft

 

Sprung Arch two firebox downdraft

 

"Fast Freddie" (Olsen Fast Fire)

 

 

and many other variations.

 

 

best,

 

......................john

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For a first wood fire, I'd suggest doing some wares with glaze on exterior and some with no glaze.  In a wood fire, you can seldom go wrong with a shino.  Kakis are a good liner glaze, as is a temoku.    On a couple of the no glaze, add a few swooshes of a flashing slip (see what the person has available to use or mix your own).  Make one ware to put on the bag wall -- mugs and yunomis are good.  Don't be afraid to experiment -- fire a ware or two on its side using seashells as support.  Have some smooth surface and textured wares.  Let the wood ash do its thing.  If you are firing a set, put them on the same shelf if you want them to be similar. 

 

Check the website of your clay manufacturer to see if they show examples of the clay fired in a wood kiln . . . ask what clay bodies work well in the kiln. 

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Make pots with thicker walls than you would typically make for cone 6. Warping and stress cracks happen a lot more in a wood kiln. So don't try to make delicate pots. Make sturdy pots.

 

Wood ash will land on horizontal surfaces. Try to design forms that have horizontal surfaces on their exteriors, such as shoulders and lids. This is another good reason to try firing a pot on its side, as Bruce suggested.

 

If you plan to glaze the exterior of any of your pots, don't glaze all the way to the bottom. Any glaze can become unexpectedly runny in a wood kiln, because wood ash is a flux. Consider adding a "glazecatcher" near the bottom. A glazecatcher is either a ridge or a groove that circles the pot about an inch or so from the bottom. If your glaze starts running down a pot, the glazecatcher should stop it before it runs onto the shelf.

 

Not sure if you will get to participate in the work of firing the kiln. If you get to help, wear natural fibers on your arms (synthetics can catch fire or melt), and shoes that are comfy but will also protect your toes if you drop something heavy.

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Thanks to all.  yes, I do get to help with the firing.  He said there will be a schedule.  Thank you to all for the advice.  I am certain he will have more info for me later, but I wanted to get an idea in my head of what to make.  This really has been a fun pottery year for me.   I took a throwing class this spring and she fires gas.  I loved the different glaze colors and combos.  Now to have a wood firing appear out of the blue!  Wow, I do feel blessed!

Great experiences!

Roberta

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I've wood fired at a community kiln with shifts.  I prefer the later shifts to finishing because you learn more even though they are more labor intensive (and generally start around midnight).  During the latter stages of the firing you learn more about reading cones, the importance of even stoking, etc.  Because  the community kiln fired wood from old pallets, we also had to introduce ash by adding pine bark nuggets along with the wood at the right time.  We also added a soda/salt solution near the very end to give the wares an extra kick. 

 

You also learn a lot during loading . . . he should be able to tell you hot spots, cold spots, proper spacing, etc.

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Roberta--you will probably fall in love!! Be prepared for periods of longing and envy if you do and then are not able-for whatever reasons-to keep it up LOL. I did not have any stoneware bodies for a last minute invite to a wood fire so I used some very small Cool Ice porcelain boxes. On the horizontal surfaces they got flashes of colors ranging from bright shiny semi-translucent orange to opaque ashy ebony and much in between, just gorgeous against the white. Sorry-no pics & the pieces are gone. It's a whole other world! 

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If you decide to fire one or more pots on their sides make sure that they are ones with flashing slip or no glaze.  You'll get nice 'shadows' where the shells or wadding is.  That's another thing to learn about...wadding.

Lin

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I was on the road for a week, but while I was gone, the wood kiln guy sent an email asking for shift sign ups, and he provided more information.  He said the kiln is similar to a manabigama.  Means nothing to me at this point, but there it is.  I do have some buff cone 10 clay and some white cone 10 clay.  I may make a variety of pieces.  I liked what Lee U. said about her porcelain.  You all have been very helpful.  Thinking about things with shoulders, I should probably make some vases.  And maybe some small lidded boxes.  He also said in his email that this is only the 2nd firing, so he is continuing to work out the "bugs". 

 

Roberta

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Guest JBaymore

A "manabigama" is the name for a specific very small anagama-style kiln designed by a specific person. (look it up.)  It is typically fired (by most people) for a shorter cycle than larger anagama.  Maybe two days.  Many large anagama are fired for 4 to 7 days.  While it can produce some very nice results, it is not known as a "heavy ash deposit" type of design.  The wares generally tend to be more "flashed" than "encrusted".  The pieces right next to the main firebox can get lots of ash... but further away.... much less so.  This has to do with the duration of the typical firing and also the size of the kiln and how that affects the draft flow.

 

For a manabigama style kiln I'd tend to do pieces with flashing slips added to "help" the kiln along.  Also use some American style high fire Shinos on some work.  Shinos are great in all kinds of woodfire kilns because they tolerate a WIDE range of cone endpoints, and simply do NOT run at all.  Most are fine from about cone 7-8 up to cone 14-15.  They take ash deposits nicely.  Many other high fire glazes can tend to run in extended multi-day firings even if the cone end points are the same as the typical 12-14 hour gas kiln firing.

 

A "woodfirer's trick":  On an unglazed form (even with flashing slip on the outside) put a liner glaze inside that is a high soda-ash shino.  The soluble sodium compounds in the glaze's water penetrate into the bisque and migrate to the outside also as the piece dry,.  This enhances flashing on the outside.

 

Watch out for lidded forms as a new woodfirer.  They have to be wadded very skillfully, and also not tend to warp due to design, forming, and clay selecdtion.  In extended firings, clay bodies that are fine at cone 10 in a gas kiln, can sag and move a lot over a multi-day firing.  This can cause the lid to slump down and make it not only not fit well (if you are lucky) but can also cause the lid and the base of the piece to come close enough to to each other in spots where the wadding is not... and fuse together from ash deposits.

 

Make yourself a couple of personal (gonna' keep em' for YOU) mugs.  Glaze the insides with a shino.  Decide on which side is the "face" (the side you want to be the focus).  Stack them face DOWN on their sides on scallop shells packed full of a refractory clay like a kaolin or a fireclay mixed with a lot of silica sand.  Set the shell holders on a little pad of the same kind of clay (like a sort of trivet).  Face the interior mug opening and the lip at a diagonal away from the flame path from the main firebox. 

 

When they come out do NOT try to immediately remove the trivet that likely will be stuck to the piece.  Place it carefully in a container of water.  That will cause the quicklime that the shells turn into (bad stuff....don't get it in your eyes) into soft goo and likely fully release the mug from the trivet.  If not tap judiciously until it does release.  Leave the mug in water after the trivet has released to continue to dissolve the remaining shell residue.  Lightly grind later with a diamond tool in a dremel to make it the w ay you like it..

 

You'll likely be happy.

 

best,

 

........................john

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I need to find a wood firer in Georgia that would let me come and fire some pots and help out. I don't know anything about it, but like you Babs I don't want to go my entire life without ever being a part of this process! I am green with envy as well! Make sure you post the results so we can all ohhh and ahhh. 

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Thanks to everyone for  support and cheers!  Callie sent a couple of recipes yesterday.  I have been taking notes on what you all have said.  I feel like I have a better shot at success because of your advice.   This will be in September, so I have time to get just the right pieces made,.....and to study up! 

 

Roberta

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