Why Are My Plates Exploding???

I bisqued a load of pots a couple of days ago. When I opened the kiln this afternoon I noticed several of the plates had literally exploded. These plates were ones to which I applied slip. I threw the plates using Highwater Raku clay and then put Highwater Helios porcelain slip on the inside of the plates. I'm 99.99% sure the plates were completely dry at the time of firing. They had been sitting on a shelf in the studio for over a week (in Florida with no central AC).

Has anyone experienced such a problem? Could it be a difference in shrinkage rate? Could it be that some moisture was still present?

Any help is greatly appreciated!

New Stuff

I finally got the studio organized the way I want it. To be more specific, after lots of trial and error, I have discovered how much stuff I can get in there and still have space to work. I now have most of my tools located within 'reaching distance' of my wheel. No more walking across the studio with clay-covered hands to get something


I recently bought a large metal shelf with wheels. Very useful:


I liked the large cart so much i bought another, smaller metal cart to hold slip, terra sig, and miscellaneous other items:


Here's a closeup shot of the small cart. It holds slip I made for each type of clay I use: Zella Stone, Loafers Glory, Raku, and Helios (all Highwater Clays). Additionally, I created a mixture of Helios porcelain with red iron oxide (8% RIO). On the bottom shelf is terra sigillata as well as some Magic Water I use to connect clay (mainly for handles).


I recently ordered some new tools from Kentucky Mudworks. They carry a line of tools made by 'Dirty Girls Pottery Tools'. I have found them to be very well made. I bought two sling shot tools, one is a straight wire and the other a wiggle wire:


The other tools I ordered were the 'Great Big Facet Tools'. Again, one straight wire and one wiggle wire:


I love the roller on these facet tools. I can't wait to use them.

I have some more things to post, but it will have to wait until tomorrow. It's getting late and I can barely keep my eyes open. Goodnight!

Terra Sigillata

Today I made a batch of Terra Sigillata. To be accurate, I made it yesterday and harvested it today.


I've been wanting to test some slip on raku ware. I made some small test plates with slip in the middle. My plan is to cover the slip with a copper black glaze and put a copper/green glaze on the remainder of the plate. I hope to fire this in the next couple of weeks. I will post my results.


I threw a stoneware plate and once again put some slip in the middle. This time I put a layer of helios (porcelain) slip with red iron oxide around the remainder of the plate. Not sure which glazes I will use on this one.


I've discovered when applying slip a little thick (as in the photos above), you must do the following:

1. The slip must not be too watery, and
2. You must dry them very slowly

Otherwise the slip will crack.

I recently purchased a couple of paint sprayers and I am about to get into spraying glaze. Until now I have only dipped and brushed. My friend John Tilton is going to give me a few tips this week at his studio. I'm looking forward to it!

That's it for now but there are currently a lot of things taking place in the stuido. There should be more postings very soon. Thanks for reading!

Upgrading the Command Center

I decided it was time to alter the setup around the wheel. I need tools to be closer while I'm throwing. Until today, if I needed a tool while throwing, I would have to get up and walk over to the shelves on the north wall of the studio. Well, no longer! I added space for tools:


I have various tools on the left


...and wooden, metal, and plastic ribs, as well as sponges on the right


For the past eight weeks I have been taking an Advanced Throwing course at Atlantic Pottery in Jacksonville. It's been a great experience. This Wednesday is the 'Pickup Party'. The last regular class was two weeks ago and we glazed all the pieces we made in class. They have been fired and we get to take them home this week.

I have one more load to bisque in the electric kiln before the inaugural firing of the new gas kiln. I plan to bisque fire mid-next week and then fire the gas kiln a week from this Sunday.

It's been a while since I've posted and I apologize. Things have been busy lately but I promise to do a better job in the future.

Thanks for visiting!

Tile Results

I fired the tiles to 1580 degrees F. It was a good opportunity for me to test out my new Oxyprobe. At the end of the firing I decided to do some reduction. The reading on the Oxyprobe was between 0.01 and 0.1 indicating an oxidizing atmosphere in the kiln. I reduced this to 0.65. I didn't do enough to drastically affect the tiles. It was more to see how the Oxyprobe worked before firing my new gas kiln. Here are all the tiles:

Here's a closeup of a few...

That's all for now.

Tile Testing

For some time now I have wanted to experiment with various chemicals applied to tiles and wrapping them in aluminum foil (fuming). Today I made the time and prepared the tiles for firing. In addition to ferric chloride, I applied the following substances to the tiles:

Cobalt Oxide
Copper Sulfate
Copper Oxide
Copper Sulfate Solution
Chrome Oxide Green
Red Copper Oxide Solution
Cobalt Oxide Solution
Copper Carbonate Solution
Cobalt Sulfate Solution

In total I prepared twelve tiles. I grouped the tiles into sets of three. Set one contained one coating of ferric chloride, set two was given two coats, and so on. Each tile was divided into nine sections (like a tick-tack-toe pattern). I put a substance in eight of the sections and left one with only ferric chloride. Here's a picture of the entire group of tiles:

I had two tiles left over so I coated them completely with some solution. Here's a closeup of one tile...

Each tile also has a few sprinkles of sugar and rock salt.

I will be firing it to approximately 1500 degrees Fahrenheit later today. I will post my results whether they are great or horrible!

Talk with you soon.

Studio Day

I spent most of today in the studio. It's been a busy weekend. Friday I took the day off and spent a good part of the day in the studio. Saturday it was the Cedar Key Arts Festival and then dinner with friends, and today it was an 'all day studio day'!

Lately I've been going through a sponge phase. I've been trying to find sponges that I like to use while throwing. I've tried several types and still not totally satisfied with any particular type. While in Cedar Key yesterday I noticed a guy selling bags of sponges on Dock Street. They were sea sponges that were harvested right off the coast of Cedar Key. I bought two bags and tried them out today. I have found my sponges!!! I love the way they feel while throwing. Furthermore, they seem to hold just the right amount of water! Here's a picture of two of them:


My cat, Moose, has been hanging around the studio a lot lately. I'm not sure if he wants to spend time with me or he's bored and has nothing else to do (probably the later). He was hanging around today so I put one of his beds in the studio. He immediately got in it and stayed there for hours...

When I was done working I started to close up the studio. He wouldn't get off the bed. I picked him up and set him down outside. As I closed the door he shot back in the studio and got in the bed. So I left the door open and I'll go out later tonight and lock up. I just looked out the window and he's still lying on his bed.

Today I put handles on some cups I made Friday. Even though I had them covered a few got a little dry. Hopefully the handles will stay on. I have them heavily covered now.


I threw a bowl and wrapped the edges back underneath and attached it to the walls. This is an experiment. Not sure if I like it but it's something different...


I finished the day by making a vase. It stands about 12 or 13 inches tall.

I hope to have enough pots to do a bisque firing next weekend. I would like to fire the new (gas) kiln within the next couple of weeks. I should have enough to fill it soon. I have a bunch of test tiles ready to go for the firing. Now I need to select some test glazes and make small batches of glaze. I've been procrastinating because I hate mixing glaze. But, it's something that has to be done. Perhaps I'll get to it this week.