Sunday, October 14, 2012

Raku Workshop, October 2012

So this summer I finally got around to scheduling a raku workshop. It's been two years since the last one. I had an opening in my schedule back in July so I set a week aside for a raku workshop. The plan was to make pots at the beginning of the week and fire them over the weekend. Attendance for the workshop was great, and we made a lot of pots.

Because my studio is in a business complex, there is nowhere to do raku firings here. So my raku kiln lives in Bristol, WI at Bristol Pottery, the studio of my friend Fred Gregory. Fred's got several acres of land, and open burning is not usually a problem. However, due to the severe drought that plagued the midwest this summer, the village of Bristol issued a burn ban two days before we were set to start firing. So the second half of the raku workshop was put on hold until the ban was lifted and my schedule opened up again.

So this weekend I finally had time to finish up the workshop. The kiln worked great and we got some wonderful pots finished. I'll post photos of finished pots as soon as I shoot slides of them.

For those of you not familiar with rak firing, here's how it works: We make and bisque fire the pots like always, but the glaze firing is totally different. After applying the raku glazes, we fire them up to 1850F degrees in 20-30 minutes. Then they are pulled from the kiln with long tongs and placed in a bed of combustible material (sawdust, newspaper, whatever) and covered with a can. We call this the post-firing reduction. 'Reduction' in this case means reducing the amount of oxygen- the burning material eats up all the oxygen in the can. This reduction causes the copper in the raku glazes to flash lots of bright colors, and causes any exposed unglazed clay to turn black from absorbing the carbon from the smoldering material. About 30 minutes later the pots are cool enough to be removed from the cans. Done!

My raku kiln

Moving a pot into the post-firing reduction.

My raku kiln is built of soft brick, with a hinged front door. In my opinion, this is the safest way to raku fire. From a safety standpoint, I have a real problem with the fiber-lined expanded steel mesh type raku kilns that require you to lift the entire body of the kiln off in order to access the pots. I think that opening one of those kilns and releasing all that heat is one of the most dangerous things potters do, not to mention the health risk of breathing the fibers that are released every time the kiln is moved. I honestly can't believe they are allowed in schools. My kiln allows someone to open the door just enough to get to the pots, and then close it again. Only the person pulling the pots is exposed to the heat of the kiln, and he/she wears protective clothing. The risk of getting burned is very minimal, and there are no fibers to breath. The other benefit of my kiln is that we can fill the kiln with up to a dozen pots, and the last one comes out nearly as hot as the first. The hotter it goes in to the post-firing reduction, the better is will look. My kiln has one power burner underneath, and the whole thing is on wheels so it can be rolled outside when we need to fire.

Tuesday, June 26, 2012

Northbrook Art in the Park

My next show. Just threw a bunch of new canisters today that I'll be unveiling there. Come see me!



Tuesday, May 29, 2012

St. Charles Fine Art Show 2012

My usual routine for setting up at an art fair is to set up my booth and shelving the night before the show, and leave my bins full of pots in the booth overnight. Then when I arrive the next morning I just have to unload the bins onto the shelves, which only takes about 45 minutes. This weekend that routine paid off big time.

I set up like normal on Friday night, then attended the Preview Party, where I got to schmooze with the purchase award patrons. Purchase award patrons are local people and businesses who have pledged to buy a certain dollar amount of work at the show, to help support the show and the arts. I met many very nice people at the party, and even sold a couple of pieces to them during the show.

Saturday morning I was headed back to the show and my car broke down in Barrington, about halfway there. The 'Check Engine' light came on and it just died and wouldn't restart. So after several phone calls to people in the area, Aunt Carlene form Elgin volunteered to come pick me up and drive me to the show.  She also gave me the name of the towing company that her family auto repair business in Elgin (Kellenberger Auto) uses, and they came right away and towed my car to the shop. Unfortunately, the shop was closed for the holiday weekend, so they are just now taking a look at it this morning. Hopefully it's nothing fatal.

Thanks to Carlene I got to the show with just enough time to get everything out of the boxes before the show started. Sales were good Saturday, although the show was never very busy and didn't have much energy. Sunday was hot, like 95 degrees, but the humidity was very low so I didn't suffer too much. The heat definitely kept people away, though, so sales were not as good that day. Overall it was a decent show from a sales standpoint, but the lack of crowds makes me question whether or not to do it again.

Added later:
Good news! My car is still alive. Just a worn out spark system. New distributor, plugs and wires and I'm good to go. My next show is the Cambridge Pottery Festival is Cambridge, WI on June 9 & 10. Hope to see you there!

Thursday, May 24, 2012

Marion, IA Art Festival 2012

Holy cow! What an amazing show! I broke my 2 days sales record by 3pm of the one-day Marion show. I can see now why this show is ranked #17 in the nation- great sales, great organizers, easy setup and teardown, and of course the wonderful people of Iowa. Here's a great time lapse video of the day: Marion Art Festival Video

Tuesday, May 8, 2012

Fishing is Awesome!

Big 'ol honkin bass caught on one of my 1/8 ounce plugs with an orange and white bucktail and a white curl tail grub. You don't need big lures to catch big fish.

New Pots

Some new pots:

I wasn't sure about this one before the glaze firing, but I'm very happy with how it came out.

Big and glossy.

15" tall.

Vessel Sink, 16" diameter.

Thursday, May 3, 2012

More Lid Success!

I've done three more firings in the big DaVinci with the new lid, one bisque and two cone 6. All were very successful. The lid only sagged an inch during the cone 6 firings, and came back up to about 3/8 inch when cool. Some of the bricks are starting to loosen up just a bit, so I'm going to have to tighten everything up before tonight's cone 6 glaze fire. I also put new elements in this week, so the kiln is like new!

Friday, April 20, 2012

Lid Prototype First Firing

Last night was the first firing with the new compression fit lid for my L&L DaVinci. Success! Before starting the kiln, the lid was sagging less than 1/8 inch in the middle. When I checked it at 1500 degrees, it was only down to 1/4 inch! This is much less sag than the original mortared lid had, so I'm very pleased so far. This morning I checked it again when it was down to 800 degrees, and it had only come back up a hair, so it may just stay there. So now I'm wondering if it will just stay put in future, or get lower with each firing. I do expect more sag in a glaze firing because of the higher temperature. Even if it starts sagging more than I'd like, I can always loosen up the clamps and adjust it back up. The bricks all look good, with no signs of crumbling. I'll be firing another bisque in two days, then a glaze firing the day after that. Fingers crossed!

Tuesday, April 17, 2012

New Kiln Lid

My largest kiln is an L&L Davinci T3427-D. It is a 20 cubic foot top loading kiln, 46 inches wide, 32 inches across and 27 inches tall (interior dimensions). It holds three 14 x 28 inch shelves per row. Due to its large size, the flat lid tends to flex a lot, and the total lifespan is not as long as on the smaller kilns. It's just a really big span for a lid held together with mortar. Seeing the lid flex and move got me thinking about other designs that might work.

Knowing that it had to be a flat lid, I immediately thought of the Minnesota Flat Top, a type of gas kiln which has a flat slab top held together by compression, instead of an arch. Last year I started talking with Stephen Lewicki, the owner of L&L, about the possibility of using the MFT design on the DaVinci. After tossing some ideas back and forth for several months, Stephen had his guys build a prototype, which I installed on my kiln today.



The new design uses compression, rather than mortar, to hold it together. The hope is that without any mortar joints to fail, it will last a really long time. The compression is provided by threaded rods with a bracket at each corner. When tightened, compression is applied in all directions, resulting in a very sturdy slab. There is almost no flex whatsoever when raising and lowering the lid.


We were able to use the existing hinge system, so no modifications had to be made to the original kiln.


The weight of the new lid seems to be about the same as the old one, possibly even a bit lighter, so the existing springs in the hinge did not have to be replaced.

I'll be doing the first firing with the new lid later this week, a bisque. I'll be putting a set of shelves up at the top of the kiln to support the lid should anything go terribly wrong, but I really don't expect any problems. Here's what I'll be watching for during the next few months of firing:

1. How much does the lid move during firings? I'm expecting it to flex downward as the hot face expands. Will it return to its original position as it cools, or will the bricks shift? If it becomes a problem, I can loosen the brackets and raise up the bricks in the middle of the lid, therefore having a slight hump in the middle to compensate for the sagging. It's a very adaptable system!

2. Will the bricks crumble as they expand, or will the metal frame flex enough to allow them to move? If they cannot move, Stephen said there is a type of high pressure bushing we can use on each corner to allow for the expansion.

3. How much will the bricks flake onto the pots as they move, if at all? Mortared lids don't generally flake, but if it's a problem, I can put a layer of old shelves at the top of the kiln to protect the pots.

Because the system is not mortared together, I feel good about being able to deal with any issues that might arise with this new lid system. It's totally adjustable. And if it just doesn't work out, then I'll put the old lid back on!

Saturday, April 7, 2012

NSUC Art Fair

First show of the season!

North Shore Unitarian Church
2100 Half Day Road
Deerfield, IL 60015
Saturday April 28, 10am-6pm
Sunday April 29, 11am-5pm


Saturday, March 10, 2012

Dinnerware Shelving

Last summer I combined a couple of shelving units to create the ultimate rack for drying plates. I can fit 30 dinner plates at a time, assuming I don't have a bunch of other crap cluttering it up. Currently my art fair booth shelving lives on the very top, and girls scout cookies take up some space near the bottom. Priorities....


I didn't have any floor space for the rack, so I put it up on the end of my work table and screwed it to the wall. I have to climb up on the table to get to the upper shelves, but that's simple enough.

Today was a productive day, and I managed to get 19 dinner plates made. To prevent the lips from drying out too fast and warping upward, I cover them with a strip of 'Caution' tape (available at your local hardware store). The middle of the plate is left uncovered for 2 or 3 days, at which time the whole piece will be leather hard with no warping at all.

Teapots

A couple of new etched teapots, starting to dry out. The green wax will burn out in the bisque firing.


One of these is for a customer, the other will be shipped to the NCECA conference in Seattle, where I have been asked to sell my work at the Lill Street gallery space.

Thursday, March 8, 2012

Throwing, throwing, throwing....

When it rains it pours. Just as I was getting started on building up inventory for the fast approaching Art Fair season, a bunch of orders came it. I can't complain, but man oh man do I have a lot of throwing to do for the next couple of months: 75 pots in the next two weeks (mostly dinner plates) plus enough pots for 3 art fairs- 1 in April, 2 in May- plus start on inventory for the other 7-10 fairs I'll have during the summer. My goal is to not be depleted of inventory after every fair, like last year. I'll do my best to post photos as I work. Time to buy some clay!

Tuesday, February 14, 2012

Best Pot Ever!

One of my students has made my favorite pot ever to come out of my studio. I present to you the M&M holder, by Avery:

Thursday, February 9, 2012

2012 Summer Art Fair Pregame Show

The summer art fair season is fast approaching. I've already applied to thirteen shows and been rejected from two. I was pretty disappointed about both of the rejections, because they were big shows- Des Moines and Milwaukee Lake Front. However today was a great day, as I was accepted to the Broad Ripple fair in Indianapolis, which is highly ranked, and the St. Charles, IL fair. Last year the St. Charles fair was my first fair ever, and the weather was horribly bad. Even so, I m ade more money than at a couple of the other small fairs I did that had good weather. So if the weather holds, this year should be great. I have never done the Broad Ripple fair, and I am holding off on accepting their invitation until I hear from the Belleville, IL show which is on the same day. Belleville is the top ranked show in the country, so I would choose it over Broad Ripple.



So, combined with the Spring Green fair, which I get automatic entry into since I won first place in ceramics last year, I've got 3 confirmed shows so far. There are a couple of others that I'm fairly positive I will get into, so this year's show season is shaping up nicely already. Time to start making pots!

Waubonsee Workshop

I'll be part of a workshop at Waubonsee Community College in Sugar Grove, IL this coming Monday. In addition to the usual throwing demos, we'll also be talking about how we each approach the business side of ceramics. The workshop is free, so be there!

Thursday, February 2, 2012

Judgemental Potter

Last Friday I was honored to be one of 5 judges at the Matthews Middle School art show. Students from 5 area middle schools exhibited their work, and we had to pick 3 winners from 4 different categories. It was very difficult to do, since there was so much good work. After marking down my favorites, I met with the other judges and we narrowed it down to the best of the best. Way to go middle schoolers!

Hard at work judging the show

Saturday, January 21, 2012

Peninsula School of Art

This summer I will be teaching a 3 day wheel throwing course at the Peninsula School of Art in Fish Creek, Wisconsin. I'm really looking forward to it, especially since I have never been up to Door County in the 12 years I've lived out here. It should be a lot of fun to work in another studio, and meet some new potters. Come take my class if you'd like, or one of the other great courses they offer.

Peninsula School of Art Home Page          PSA 3-D Courses          PSA 2012 Summer Catalog

Thursday, January 12, 2012

Kiln Controller Safety

Today I replaced a controller on a customer's Skutt kiln. It was the wall mounted type, but it uses the same parts as the kiln mounted systems. The controller had fried out, and there's no good way to fix them. By the time you send it off to have it repaired and pay for shipping and labor and everything else, it's faster and just as cost effective to buy a new one. Currently, a new Skutt KM circuit board with touch pad is $260. Replacing it is fairly simple, but you have to make sure to get the wires hooked up in the right order.

When controllers fail, they do all sorts of goofy things. The most common symptom that I have seen is when some of the buttons stop working, like on the controller I replaced today. The Cone Fire section of the board wouldn't work, and some of the number bottons were dead, but the Ramp/Hold section worked fine. Another common symptom is when the bottons still work, but the controller simply won't go when Start is pushed. The most difficult diagnosis I've had was on a very old controller that seemed to be working fine, but every few minutes the temperature readout would jump several hundred degrees for a few seconds, which would confuse the system and shut it down. Replacing the controller fixed the problem.

I worked on a kiln this last summer that was only two years old and was having trouble getting to temperature. It would just stall out at 2000 degrees, then shut down. Due to its age I didn't think that it was a controller problem, and the elements weren't necessarily worn enough to blame them. After changing the thermocouples and thermocouple wires the problem persisted. So I changed all the elements, still with no success. So I switched out the controller with a controller from one of my kilns and we still had the same problem. After talking with the tech at L&L Kilns, and the tech at Bartlett Instruments (they build the controllers for L&L and Skutt), we decided it was in electrical interference problem. We have no idea why this suddenly started happening to a two year old kiln, but it was fixed by adding a grounding wire to the center tap of the control board. It took a couple of weeks to get through all of it, but it's now working fine.

What makes a controller go bad? Age, moisture or an electrical surge. How do you keep your controller healthy? Keep it in a dry environment, and shut down the breaker when you're not using it. I've had several schools fry out controllers by leaving them on during the summer months, when we get a lot of electrical storms.

With minimal care and fuss, a kiln controller will last many years. But like any computer, they eventually wear out and need to be replaced.

Tuesday, January 3, 2012

Clay Selection

Today is the first day of a very busy pottery class session. I'll be teaching 8 classes a week during January, with lots of beginning students. I always start my new students with a short explanation of how we choose the clay bodies that we use, so I thought I'd go ahead and post it here as well:

The clays that we use to make pots are not a single clay dug from the ground. Rather, they are are a mixture of clays, binders and texturizers that are mixed to a specific formula or recipe. We call these mixtures 'clay bodies'. Every company that mixes clay bodies has their own proprietary formulas. For better or for worse, a cone 6 Buff body from one company will not be the same as a cone 6 Buff body from another company.

Clay bodies are formulated and purchased according to 3 main criteria: color, texture and firing temperature. Color is determined by the amount of iron oxide present in the clay body. Porcelain has no iron, white stonewares may have trace amounts, and stoneware bodies can have a small amount to make the body a light tan color, or a large amount to make it dark brown or brick red. The color of the clay body is important because it will affect the color of your glazes. The darker the clay, the more it will darken the glaze.

The texture of a clay body can range from very smooth to very gritty. Grit is obtained by using fire clays in the formula, or by adding grog (ground fire bricks) or silica sand. Grog and sand are available in a variety of sizes, but usually range from 20 mesh to 100 mesh when added to clay bodies. The smoother the clay body, the less forgiving it will be, meaning it will shrink, warp and crack more, therefore requiring good throwing and assembly skills. Large, thick or uneven pieces like sculptures generally require a much grittier body than wheel thrown pots to keep them from cracking during drying and firing.

Last, and probably most important, a clay body must be formulated to fire at the right temperature. If you are using cone 6 glazes, you must use a cone 6 clay body. If you are using cone 06 glazes, you must use a cone 04 clay body. If your clay and glazes are formulated to mature at a different temperature, they generally won't 'fit' together very well, and a multitude of problems can arise, from crazing to shivering. And if you over-fire a clay body, it can melt into a puddle all over the inside of your kiln. See HERE.

So there you go. If you need help selecting a clay body, the tech at your local ceramic supply store can help you out. They know their clay bodies very well, and can help you pick the right one for your project.