After being without a kiln for the last 11 month, I finally got my kiln! It’s an L&L Davinci x3236-D Automatic. I have been asked many times how I chose my kiln. It is a huge decision to make, so I wanted to share my thought process and maybe it’ll help someone out there make their choice a little easier.

First decision: What kiln manufacturer did I want to go with? This was the easiest part of my decision. I’ve long coveted an L&L. They have a number of design features that strike me as both brilliant and completely logical. The big ones are:

• The element holders are hard brick. Makes sense, right?
• The electric controls are separate from the kiln. Sensitive computer parts are kept far away from the heat. Again, very logical.

The other thoughts I had about what manufacturers to go with.

• I have had a lot of experience with Skutt kilns. Lillstreet had a ton of them. The 2nd floor set of kilns didn’t get particularly high usage, but it seems like there was always one down for one reason or another. More often than it seems like they should have. I’m sure there are lots of people who swear by their Skutts, but based on this experience, I didn’t want to go in that direction if I didn’t have to.
• Any kiln is going to run into a problem at some point. So the question is- how are you going to fix it? If you’re super handy, it might be something that you can tackle yourself. If not, then who? A friend of mine, Donovan Palmquist of Master Kiln Builders is a dealer and repair person for L&L so I knew I had that covered. Plus I was able to order my kiln through him. You can also contact your local ceramics supply place and ask them if they have a repair person for a particular manufacturer. If you don’t have a supplier nearby, ask other potters in your area. Or you can also call a company directly and ask them to give you the name and contact information of a dealer/repair person in your area. Hopefully it’s not something that you’ll need for a while, but it’s good to know ahead of time so when the kiln breaks right before your last firing before a show, you’ll know what you need to do in the midst of your state of panic. Also, L&L has a 3 year warranty.

Second part of the decision: Size and shape.

My long term plan: Sometime next year, I am planning/hoping to build a soda kiln in my back yard. But I want to progress with making work right now, and not just wait until the soda kiln to happen. So I wanted a kiln that I can take up to cone 10. Even after I build the soda kiln, I want to be able to high fire non-soda pieces. A couple of years ago, I started making a lot of c.10 (reduction) dinnerware, or sometimes designed place setting that were a mix of soda and straight reduction (specifically tried to avoid dinner plates in soda). I wanted to build that option into the kiln I got. For the interim, I want to be ready to fire work in friend’s kilns- soda, wood, salt, etc… and not worry about clay bodies, etc… And hopefully there will be some glaze overlap too.

The other part is that I didn’t want to outgrow the kiln in 6 months. I want to make larger work- wide platters and tall bottles. Especially once I have the soda kiln- so I need to be able to bisque larger pieces. At this moment, I plan on having the footprint of the soda kiln be two 14″by 28″ shelves. The interior of my new L&L is 30.5″ square and the height is 36″ which will allow me to make the size pieces that I want to. I ended up getting a larger, more expensive electric kiln than I had originally planned, but it would ultimately be more expensive for me to buy a 2nd kiln in a year or two. So I had to wait a little longer to get the kiln that I knew would fit my needs now, and in the long term.

Shape. The square makes sense to me. Whenever I load octagonal kilns, I often get frustrated. Do I need to say more than that?

Below I’ve included the specs of the kiln (from L&L):

Specifications

• Internal Size: 30 1/2″ square x 36″ high
• Number of Sections: Four
• Brick: 3″ of premium select K23
• Max Temp: 2350F, 1287C, Cone 10
• Control Panel Mount: Floor Standing, Plug-in, separate from kiln
• Control: Handheld DynaTrol with Dynamic Zone Control, 4 preset programs, 6 user defined programs
• Industrial Thermocouples
• Hinge: Spring Loaded Counterbalance
• Stand: Heavy-Duty Welded Angle Iron
• Power Hook Up: Direct Hook-Up
• Heavy Duty Elements
• Three Year Warranty
• Listed to UL499 Standards

And this is the vent system for the L&L kiln:

VENT-SURE KILN VENT SYSTEM

• WALL MOUNTED VENT BLOWER

The vent blower motor is mounted on the wall. This keeps the heat of the kiln away from the motor (for long motor life) and keeps the motor vibration away from the kiln (which can cause ware to move, damage to the kiln, and misfiring of cones on a Kiln Sitter).

• VACUUM IS SAFER THAN PRESSURE

The vent tubing is kept under vacuum instead of pressure (unlike competitive brands). This insures that any leak in the tubing does not blow noxious fumes into your room.

• EXTERNAL VENTING IS BETTER

External venting is safer and surer than venting to the inside of your kiln room with a filter.

• LARGE CAPACITY

The blower vents up to 130 CFM (cubic feet per minute). This will handle up to a 20 cubic foot kiln (and usually larger). More than one vent can be attached to a kiln. Only 1.37 amps.

• SIX FOOT POWER CORD WITH ON/OFF SWITCH

The blower motor features a 6 foot long 120 volt 15 amp power cord. An On/Off switch is located on the cord.

• ADJUSTABLE VENT CONTROL

A vacuum bypass on the kiln bypass/collection box adjusts the amount of venting from the system. Don’t waste heat and energy by venting more than you need. Adjust vent to kiln size.

• 15 FEET OF FLEXIBLE ALUMINUM DUCT

15 feet of flexible expandable aluminum 3″ diameter duct is included along with necessary hose clamps. Longer lengths or lengths of 3″ stove pipe can be used as well. Length can be as great as 60 feet horizontal or vertical with up to four 90 degree bends.

So there is still some work to be done. We had our electric service upgraded so it can handle the kiln. Every kiln manufacturer website has these specs listed.

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I have taken a lot of safety precautions since my kiln is in the basement of my home, and I have a couple more that I’m going to add in before I do my initial firing. I know all about being overly cautious of the out-gassing, etc… But if you have any specific safety features that you have taken in your space, I’d love to hear about them. I will do a future post on that part of the kiln installation since I think it deserves it’s own post.

I’m going to spend some serious time reading the manual now. It is a very full 3 ring binder. One caution that’s in the book is not to plug it into an extension cord. That totally cracked me up. Seriously, though, there is a little more electric work that has to be done before I can fire. We just did a major service upgrade to accommodate the power draw of the kiln. Before you actually purchase your kiln, look up the kiln on the manufacturer’s website and look up the electrical specs. Print out the info sheet and have it when you have an electrician come do a bid. And get at least 3 bids. Really.

For privacy reasons only post kilns submitted by the owner’s of those kilns will be added.

If you would like to add your kiln to the database: Please email Simon Levin, simon@woodfire.com with the following information: 

• Type of kiln
• Size in cubic feet
• Street address and zip code
• Any information as to what the kiln building looks like, ex: green roof or to the east of the house
• Contact name and information
• Any website you want linked to the information

This would be a great thing to do for soda kilns too…maybe after I move…

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Another great project that Simon has been working on is The Studio Potter Collector Card Series. Its a fundraiser for my favorite journal: The Studio Potter. This is the first in a series of 3 packs of 11 and includes MVP’s and Rookies :)

As I mentioned in my last post, I fired my first soda kiln of 2009 last Sunday.  I unloaded it on Wednesday between classes and managed to snap a couple of quick pictures in the process.  We’ve been having some crazy weather here in Chicago that has kept me from going back to my studio to spend some time with these pieces and to take more pictures. We’ve had back to back to back snow storms and it got cold enough for the thermometer to hit -15°F. That meant that I didn’t get back to the studio to take some decent pictures before heading out for a road trip, but I thought I’d share a quick sneak peak from the unloading.

I’m hoping that I can figure out a way to capture the surface of this piece.  It is full of little sparkly crystals. I’ve never had crystals develop over such a large area in this kiln before. Of course you can’t see them in this picture, but you can see the kiln wash splattered floor in the background!

This is one of the espresso cups and saucers that I mentioned before.  This sweet little cup is maybe just under 3″ tall.  While I was unloading, I discovered that one of these saucers mysteriously made it into the kiln without any wadding… oops!

I’m regretting that I didn’t take a pictures that had any sense of scale.  This teacup is much larger than the espresso cup above.

This firing was all part of a large dinnerware set from a wedding registry that I have been working on for my friends Beth and Lars.  Hopefully I’ll get some better photos of the set to share here soon.

Online Soda Groups:

Salt/Soda Firing Discussion Group

You might remember this site that is all about Salt and Soda firing that I wrote about a while back. It’s a social networking site for all people interested in these firing processes. There are some fantastic potters and sculptors that are a part of this site as well as students who are just beginning to dabbling in soda. I highly encourage you to dive in- sign up and make a page. The more the merrier (don’t be shy if you’re just beginning in soda!) There are recipes for slips and glazes as well as a forum for putting questions out there. Are you thinking about converting an old electric kiln into a soda kiln? There’s a discussion going on here for you. And this site is always evolving- it’ll be whatever the members make it.

Salt & Soda tags on the ClayArt archives on Potters.org. It’s worth digging into. It’s quite possible that someone else had the same exact question as you 8 months ago.

Blogs that focus on soda firing:
(I had to draw a line somewhere… so I drew it at soda firing bloggers. If I’m missing any, please let me know!)

Of course there is this blog, PotteryBlog.com. About 95% of my pots are soda fired, and I try to share with you interesting soda information. Soon I’ll be posting a whole bunch of information about the use of whiting in my soda mix (the soda geeks will be psyched for this one!)
Here are some posts that you might find extra interesting if you’re a soda firing fool:
What is Soda Firing
A Happy Soda Firing
Hot Pots 

Scott Cooper makes beautiful wood & soda fired pots. He also writes about his work and process in his journal, This Week @ St. Earth. You should also be sure to check out his “process” page where he has tons of information that is interesting and helpful.

I just discovered Joy Tanner’s Blog. I’ve gotten to know Joy’s work through the Salt/Soda group and I’ve excited that there is another soda firer writing a blog!

Websites that have a wealth of soda info on them:
(These are sites that have information on them about soda firing- kiln info, recipes, etc…)

• Julia Galloway’s Alchemy page. Julia generously shares with her information on cone 6 soda firing, including slip and glaze recipes.

• Scott Cooper (as mentioned above) has a great process page with tons of information on kiln building, glaze recipes and even clay recipes. Not to mention some beautiful pots!

• Bill Buckner’s site, sodaglaze.com is full of soda info. There is a great article on soda that you should check out. He also has a bunch of recipes and firing info.

• Robbie Lobell makes beautiful, elegant soda fired ovenware and tableware. He has a page on his site about his kiln and soda firing process. He lives in Coupeville, WA mentions on his site that he will rent out 1/4, 1/2 or the whole kiln to experienced firers.

Books on Soda Firing:

Soda, Clay and Fire by Gail Nichols is a must have for anyone interested in firing with soda. This book is the culmination of Gail’s PhD work in soda firing in Material Science at Monash University in Gippland, Victoria, Austrailia. The research is incredible and it’s an easy read. Two things that don’t always go together so easily. I think if you picked up this book knowing clay, but not knowing soda, you might decide that you need to start soda firing by the end. But I’m a bit biased on these things. You can also learn a bit more about this book here.

Online articles about soda firing:

• Salt and Soda-glazing article on Ceramics Today.
• Soda Firing by Robyn Gough on Avicam.
• A New Soda Kiln: a kiln conversion project by Robyn Gough, Maryke Henderson, Robyn Whitworth on Australian Ceramics.
• Why Soda Glaze? by Maryke Henderson on Avicam.
• Soda with Sparkle: A profile of soda glaze specialist Ruthanne Tudball by Judy Adams in Ceramics Monthly.
• Painting with Fire by Gail Nichols on Ceramic Arts Daily.
• In the Soda Zone by Mark Bollwinkel on Ceramic Arts Daily.

Videos about soda firing:
(if you’re reading this through your email or a blog reader, you’ll won’t see the videos below. Just head over to Pottery Blog to see the videos)

From Pottery Northwest:


And a series of 3 informative videos from Jeffrey Huebner:



I really have enjoyed this. Please send me links to things that you think might be missing from here and I’ll keep updating this post. This was a big project and I had to put some sort of limits on it. I decided not to include links to soda firing potters & sculptors in this post. I know that there a ton out there with great websites, but I thought I’d limit it to sites that had technical information on it. Another post will be soda firing ceramicists. That will be fun ; ) If you want to give me a hand with that, just leave a comment with suggestions for me to include. Just remember: folks who fire with*soda* or *soda/salt,* but not just salt.

I’ve been using a pyrometer for the last 5 years and I have come to I love them! There can be problems with the cones in a soda firing and the pyrometer can be a great backup to the cones. Around c.6, the residual soda in the kiln can start to vaporize. Sometimes this soda can hit the cones and “freeze” them temporarily. Then all of the sudden, it “unfreezes” and the cones fall quickly. Then sometimes the soda can flux out the cones prematurely. Sometimes the cones on the top melt prematurely and the cones on the bottom freeze. And sometimes they are fine and go down when they are supposed to go down. By using both the cones and pyrometer, I feel like I am not firing totally blindly. Neither is perfect, but when used together, I have enough information to comfortably fire with.

There are 2 types of thermocouples that potters use, type J and type K. Type J is rated to about 2000′ F, and type K is rated to almost 2500′ F. The pyrometer is the same for both thermocouples, you just have to push a little button to switch from one type to the other. For the beginning of the firing, if you have it accidently pushed to type J when using type K, it will read normally. Then all of the sudden, your perfect firing seemingly goes crazy. For a couple of minutes, you think something is wrong, even though everything was going along just fine. Don’t make any adjustments, don’t play with the damper, don’t turn up the gas or air. Just check the pyrometer and make sure that the setting for what type of thermocouple you’re using is correct. Nothing has actually happened to your firing, it’s just that the gadget wasn’t working properly (user error). I teach people pretty regularly how to fire kilns and so I get to see that certain “mistakes” are common. This is one of those common mistakes.

I had been told by a couple people last month that they were having a problem at the end of their firings. After all the soda was in and the kiln was continuing to climb, something weird kept happening. The kiln dropped 15 degrees for basically no reason. Adjustments were made and the kiln started to climb back up. It was odd; I had never seen this happen before. Then it happened 2 or 3 times in a month. I chalked it up to firer error (just being honest here). Then I fired. I was having a great firing. I was within 2 degrees top to bottom from c.010 on. The soda went in at c.9 and the kiln continued to climb. Nearing the end, I thought I had about 20 minutes left before the kiln was to be shut off. I checked the kiln for what I thought was the final check, and it had dropped 15 degrees! What happened? This couldn’t possibly be a firing error if it happened to me (hee hee). I managed to finish off the firing and the next day I talked with master kiln builder, Donovan Palmquist. His thoughts on this weird problem was that basically the thermocouples were fried. What was happening is that the pyrometer was acting totally fine up to about 2300′F. Then it was starting to freak out at about 2300′F. If the thermocouple is exposed to soda, then that can really cause trouble. I use a ceramic protection tube to encase the thermocouple so it isn’t exposed to the soda, so I wasn’t quite sure why there was suddenly any trouble. When I unbricked the kiln I discovered the problem. There was a crack in the protection tube, but it was in the first 9″ so it was hidden by the brick. Once I pulled it out I found where the soda was getting in. New thermocouples were wired up. Problem solved! When I fired on Wednesday, it went up without trouble. Luckily I always keep a couple of extra thermocouples and protection tubes on hand for when these problems come up. (That was a lesson that I had learned early on in my pyrometer experience.)

One other way a misreading can happen is that the little prong end of the thermocouple that is plugged into the pyrometer might not be in quite all the way (it doesn’t snap in, so it’s not as easy to tell if it’s in all the way). If it’s not in all the way, it can give you a reading that is close to normal, but not quite right. Always check the wires and attachments when the kiln seems a little bit off. Wiggle them around until they “calm down” and settles on a number.

The moral of this story is to enjoy your thermocouples and pyrometer, but always be skeptical. It’s a sensitive piece of electronics that you’re using in and next to a very hot kiln. Before you freak out and make all sorts of adjustments, calm down and listen to your gut instincts with some logic thrown in.

For another very important studio lesson, check out Keith’s tip from earlier this week.

This is what the back of the kiln looked like before the firing:

And this is what it looked like after:

The back third of the kiln is usually has less soda than the front. I load porcelain or white stoneware clay bodies in the back of the kiln that do nice things with less soda to take advantage of this area. If I try to put my soda body in the back of the kiln it will be rough and dry. Not a nice look. I also load the kiln more loosely to encourage the flame to head back there. 

And this is the front of the kiln before:

And this is it after:

The kiln had mixed results for me. The pieces that I’m excited about I am really excited about. The ones that did not turn out so well are disappointments. But that is why I do soda. I’d much rather have the highs be really high and the lows be really low than to fire a kiln and say “oh, that’s just how I thought they’d turn out.” And when you have a kiln that you’re doing lots of experimenting with, those extremes are even more extreme. There will be lots of pictures to come, but I thought I’d give you a peak and some of the cups.

Please excuse my less than excellent pictures. I snapped them quickly in my studio last night as the sun was going down. Snazzy pictures will come in the not too distant future. I want to get better images of the test pieces so you can really see what’s going on.

You might remember these masked mugs:

And perhaps you remember these too:

peace – hope – change 

And this is a little preview of some new pieces to come:

(I love this new clay body!)

I recently came across this great article on the Australian ceramics website Avicam: Why Soda Glaze? It’s a lengthy excerpt from Maryke Henderson’s Bachelor of Arts research report from Australian National University School of Art in 2005. It covers everything from “What is soda?” and the historical background of soda to technical information on soda introduction and it’s corrosive effects on kilns. There are profiles of contemporary soda artists as well as a statement about Maryke’s own work.
The photos that I have included of Maryke Henderson’s work are from Avicam. They are elegant pieces that both intrigue me and make me very nervous. Enjoy the article and the beautiful images. When you’re done reading Maryke’s article, spend some time wandering around Avicam. It’s filled with interesting things to read and some really great pots to look at.