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I have been accused of being wordy so lets get right to it. My latest hobby is clay and pottery, Im learning alot from the following folks and want to thank them for that.

Youtube channel PrimitiveTechnology I don't know this guys name but his video on Termite clay kiln & pottery is what started me down this trail and I am having a blast.

Youtuber Paul Iascau's Studio his video building a small wood fired kiln was the basis for my design.

Crane Yard Clay these guys have been instrumental at helping me as I begin to learn a little about clay, pottery, ceramics, kilns, Thanks guys!

I decided to try building my own wood fired pottery kiln and thought somebody might like to see it. So here are some pictures and maybe some videos will be added later.

Blocks were stacked to raise the kiln and make it easier to stoke over long firings. Then an old washer tub was used to help keep the shape round as I layed the brick. Red bricks were used instead of firebrick because it's what I was able to get inexpensively. The kiln body and fire box base were laid and then the rebar was added. The firebox is designed so that air can get under the fire and will be drawn up through the coals. The idea was to built a sort of dakota firepit effect. I built in the possibility of forced air so the back of the firebox at the bottom is blocked forcing any air forced in up through the fire. The fire will be built on top the rebar. One thing I did not consider is whether the cinder block will take the heat. If I have to put a layer of brick over them my opening to the kiln for fire will be smaller than I had planned. So we are going to try it like this. after laying out the rebar about a half brick apart the remaining brick was laid for the kiln and firebox. Just before starting the dome the washer tub was removed. and the firebrick shelf was cut. This turned out to be bad since on the last trim of the shelf I broke it right in them middle. So we simply decided to make due with the broken pieces for now. The entire dome minus the viewport (not pictured) and the opening for adding and removing stuff was covered with 200 lbs of "frosting" made from self dug clay mixed about 2 parts clay to 1 part play sand and pressed into all the cracks and crevices and smoothed. After a day of drying time relief lines were cut to allow help reduce random cracking. This was somewhat successful but we still had a lot of cracking.. Im am contemplating what if anything to fill the relief lines with after we are bone dry. I am also considering something that most will find hysterical. I am wondering if I burnish the whole kiln then wrap it in a couple layers of fiberglass insulation if I can achieve atleast some level of firing on the outer kiln walls. Then remove the fiberglass and hopefully have something that repels water a little better than the clay would have without burnishing and heating to whatever level I might achieve...lol

Before the second firing I plan to replace the broken kiln shelf and maybe add some stand offs and a second shelf and depending on what temperatures I am able to achieve and maintain maybe make and fire some saggars for use in glazing. But we shall see I am so new to all of this I have no idea what to expect from my creation.

UPDATE: We had the first firing of the kiln on Sept 2. 2017 - 9 pieces went in - 7 pieces came out successfully fired - 2 failed during the firing.

Here are some pics and videos from the firing.

These are the parts going into the first kiln run - from left to right

Top Left -a bowl carefully smoothed, carved, dried and painted with some Amaco Velvet Underglaze in light pink and jet black.note the jetblack looks more like medium gray. Below that a 3/8" thick round disc on which I carved a nordic triskelion. Next is a thrown jar and lid made customer order for a friend. This little bowl and lid was hard to let go. It would later become an interesting combination of firsts and onlys. It was the first piece I successfully threw on a wheel that made it to firing. It wound up being the only successfull piece from a small hobby pottery wheel given me by a neighbor before the wheel died. It was the first successful piece to go into and successfully come out of the wood fired kiln I built. It was the first piece I ever made and successfully fired. And the first finished and fired piece of my work I gave away and the first ceramics order I completed. From start to finish - I dug the clay, processed it, aged it, wedged it, put it on a wheel and shaped it, trimmed it to the ordered specifications, trimmed it from the wheel, threw the matching lid and tripped and shaped, dried them for over a month, then oven dried them, then built the wood fired kiln and fired them in it. Next in the back with pink ribbon is a heavy planter. This started out to be a jewlry box for my wife but she advised me that "I don't wear jewlry and therefore have no need for a jewlry box can you make it something else. I cut off the side instead of the top and called it a planter..LOL. In front of it are two 15 cm discs approx 1 cm thick with several 10 cm lines cut on them when there were wet to guage the shrinkage of the clay. Shrinkage would later turn out to be 8% and two 10 cm long by roughly 5/16 diameter logs also for measuring shrinkage. The large disk on the right and planter would not survive the firing in tact everything else comes through unscathed and complete.

The pieces aranged in the kiln ready to fire. Note the brick sticking in from the back. That is the brick filling the view port hole.

The kiln loaded up and ready to light the lighting took place Sept 2nd, 2017 at 7:51AM Central

Kiln lighting Video

A peak through the view port just after lighting. We slowly raised the temp for the first hour then about 9AM started pouring on the heat.

we used all manner of wood fuel for the kiln from left over construction lumber, to storm downed green limbs and cabinet shop cut offs. Then I added a 6 in 200 CFM blower to warm things up even more.

at 11:00 the flames were rolling but the parts werent glowing. Did some adjusting narrowing the flu port, and adjusting how much and how often and I was adding fuel and how much I was adding at a time. Some trial and error but by 11:30 thinks we starting to perk up

and by 12:43AM we had her up to what I believe was a good temp.

and the parts inside were glowing red hot this frees the 2 water molecules bonded to the clay molecule and forever changes the molecular structure of the clay. The clay is now pottery, Some Pottery is now fired beyond this phase up to 2400 degrees farenheight or so to make it harder and less absorbant. The next firing of the kiln will be even longer and we will shoot for even a richer brighter glow.

for this firing we locked her down about 1:30 pm shuting down all air movement in or out the best we could. 7 hours later the outside top of the kiln would still boil water instantly.

A peak through the view port 6 hours after we locked it down.

and again at 7 hours after lock down

First Kiln Opening Video 9-3-2017

At about 23 hours after lighting it it was cool enough to take the finished products out.

The end result

My first happy customer!

Alot of learning happened during this firing. I think the firing should have been longer, ramping up to speed slower, and I now know how to control the fuel and airflow better to get to and maintain the temperature. A full diatribe of what I learned from the first firings and what plans I have to update the kiln before the next firing. follows:

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so, take aways (lessons learned) from my first ever firing in a wood kiln. And my first use of a kiln I built.
1. Im too old to be getting down on my knees and up again. If I ever build another I will build it higher so I don't have to kneel to feed it and don't have to kneel to look through the view port.
2. The flu outlet should be no more than have the size of the air input in order to hold more heat in the kiln. The kiln did not get hot enough to fire properly until I reduced the flu opening to about 2.5 inches by 5 inchs. up till then I think most of the heat was going right out the top. 
3. The forced air was a requirement with the small firebox I would not have been able to hit the temps needed without it. Most importantly the 240 cfm duct fan was the perfect level of air flow.
A better ash drag tool is needed to keep the air flow open.
4. Very important - If its smokin out the top you have to much fuel for the amount of air. The best heat was achieved when the the level of fuel and air was balanced so that the output from the flue was clear and hot with no smoke.
5. a couple of extra feet of duct between the fan and firebox would keep the air guided to the coals and keep the fan back from the firebox reducing heat on the fan motor.
6. POSSIBLE TAKE AWAY - I think a solid shelf that does not require support under it might have saved the planter. by allowing flame and heat to be more even in the kiln. The explosion of the planter happened less than 30 min after the end of the preheat phase. so I think it may have been due to heating to much on one side and not enough on the other. A clear area under the shelf would allow heat to flow fully to the back of the kiln and up promoting more even heat. additionally raising the shelf above the top of the firebox would stop the heat from blowing directly on one side of the articles while leaving the other sides colder. Lastly raising the temperature from preheat to max more slowly might also have saved the planter, 
7. Raising the shelf and making it solid without a brace in the middle provides the added advantage of protecting the work pieces from the possibility of pushing fuel back into the work during stoking.
8. Good quality welding gloves THAT FIT are a requirement for efficient stoking.

Changes based on take aways -
1. I cant raise this kiln without tearing it down and rebuilding it. So I will have to make due for now.

2. I will block the flu down near the end of the preheat cycle next firing which should up the temp near the end of the preheat and coupled with slow build up of stoking should create a more gradual increase in temperature.

3. Get or build a more efficient tool for dragging out ashes.

4. Balance stoking to keep smokeyness to a minimum. and increase heat. Then maintain a more even heat through smaller more continuous smoking.

5. add 2 to 5 feet of duct between fan and firebox

6 and 7 replace broken shelf with solid shelf and raise it above the top of the firebox. with no middle support.

8. Get gloves that fit.

Lastly adding pyro cones and a hi-temp thermometer would help guide good stoking to attain the correct temperatures and verify I have maintained them long enough to meet firing requirements with less guess work. Lastly while it seemed the kiln held temp well. More insulation on the outside should help to hold the heat even better and reduce the amount of fuel needed and stoking required. So it just makes good sense to cover the think with a good bit more insulation. I'm considering a 6 inch think pile of dirt.

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Update 9-13-2017 We have begun the kiln upgrades in preparation for the second firing.

Came up with a different idea to better insulate the kiln - I used the leftover bricks to build another full layer and 2/3rds around the whole kiln.

 

Im gonna have to change the view port to make up for the added thickness and probably cast my own viewport plug from refractory cement. I raised the view port already. Removed the broken kiln shelf and now am looking for a replacement. and looking for refractory cement to make the view port plug out of. And looking at wood options for firing #2 I will keep posting here as we continue the updates and get ready for the next firing.

Hey Hey Hey - Its Saturday Sept 16th, and Thanks to a happy aquaintance made on Facebook Marketplace the latest addition to the Burris pottery experience is a 1992 Brent Model B pottery wheel

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Looking forward to seeing how big a mess we can make with this!