DIY Attack

The kiln has been put on hold for a few days. We have a visitor coming so I decided to tear out the disgusting carpet in the guest bedroom and put down new flooring. No problem, one day job. This, of course, lead to the discovery that moisture had seeped through the cinder-block and caused damage to the drywall. So...out came the drywall and I am sealing the block and rehanging the dry wall, taping and floating it, painting the room...and then putting down the new flooring. All with a deadline. Where's HGTV?

Porch Thoughts

My eyes scanned the green wall of trees this morning as I sat drinking my coffee this morning. I was looking for hints of the coming fall. They were there; very subtle, but they were there. A few leafs gone to orange, yellow and brown with a worn, tired look to the rest. We had a cold front slide through a few days ago and it signaled to the hummingbirds that it was time to take their long journey south again. A few still hang on, like the last guests at a party unwilling to call it a night. I love the celebration of fall with its bright colors and invigorating weather. The time of year makes mindful the cycles of life that the seasons unfold. The birth of spring, youth of summer, the full bodied maturity of fall and the quiet passing of winter. My mind scans myself, fully seeing the autumn within.

Devil in the Details

What they don't mention is that bricks, Super, High, Medium and Insulated Fire Brick (IFB) are not the exact same size. I am using the 3" x 4 1/2 x9 inch series of brick and have mixed the various grades of bricks in the kiln. I used Super duty around the firebox, High duty for the inner shell and medium duty for the door and upper chimney. The outer shell is made from IFB. As you can see from the photos below, these bricks differ just a bit in height. If you are using a mortar, then the difference is taken care of. I am doing a bit of mortar in critical areas, but for the most part I am dry stacking the bricks with just a skim coat of fire clay and sand to seal and level a bit.








So at the header course, I have to deal with cutting the IFB back level to the hard brick. A pain, but not too bad as the IFB easily cuts with a hand saw. Unfortunately, my brick saw will not handle the brick on edge without making a double cut. The 4 1/2" is just too tall to make the cut in a single pass. Only two more header layers to go, layers 14 and 18. Layer 18 is the base for the arch.

Sunrise over the Highland Rim

Greeting me this morning as I stumbled my way to go for my jog was the sun coming up over the Highland Rim here in Tennessee. It is one of my joys.



The MOMA in NYC put out a facebook post yesterday that I enjoyed. It was a video on MIT TechTV called Metropath. Being an engineer/artist or is that artist/engineer or maybe enginartisteer, I really enjoyed the concept. It is worth a look see.

As to being a very anal retentive engineer, here is a new use for a banding wheel: a transit. I use it to find the high corner.

Change Order

I decided to make a change to the design, I wasn't happy with the way the door was going in. I was fussing a bit of the hard brick sitting on the IFB with it being put up and taken down with each firing. So.. I did the following:





I got layers 7 and 9 in. Now it time for a header layer - and mow the lawn,

Burn, baby burn!

I mentioned the burners yesterday so I thought I would show a picture of one of them. I bought two from Ward Burner Systems. They are a Ransome B4 Venturi burner with a BASO safety system and a Piggyback Venturi pilot. They are ported for natural gas and I intend to operate at up to 6 psi. I had to work with the gas company to make sure they would supply gas at this pressure. They were extremely helpful and actually ran me a dedicated line for the kiln at no cost to me. They hope to make their money back in the usage. I hope they do, too.



Yesterday, as promised I pretty much took the day off. I did unload the cone packs from the test firing of my electric Cress kiln and found as suspected that the controller is firing it too hot. I set it for cone 5 and when I pulled the packs cone 7 was down on all three packs that I put in. Good news is that they were even from the bottom of the kiln to the top. Now, I will have to see if I can get it calibrated.

My friend Ellen accused me of talking engineer speak yesterday. This is more potter speak, but a couple of terms that people might not know. Venturi burners use the release of gas at pressure to cause a vacuum to pull air into the burner to mix with the gas and then burn. The effect is named after Giovanni Battista Venturi (1746-1822)

Cones or more correctly, pyrometric cones are means of judging the temperature of and amount of heat that has been added to the pots. In the new computer controlled kilns, the internal program tries to match the way these physical cones work. Sometimes the computer gets off and you have to wack it a couple of times to get it back on track - just like me.

The Goal

Here are a couple of views from my Rhinoceros 3D model of the kiln. This is what I am trying to take from virtual space into studio space. This is revision B as it originally was about 30% larger, but John Britt convinced me that a smaller kiln and cycling more was a better learning tool. And that is where I am definitely at - just beginning to learn. It has about 22 cf of stacking space which I can fill in a couple days of throwing so turn around time on firings, considering a bisque fire, glazing, firing and clean up could be as short as two weeks.







As you can see it is a downdraft with a below the floor flue exit. I like to make tall pots so I made the kiln taller than usually would be recommended for its width. I am hoping with the floor flue I can get a uniform temperature top to bottom. I know I am going to have to empirically play with the bag wall once the kiln is done. That is unless someone wants to donate a huge amount of money so I can do a thermodynamic finite element analysis of the forced convection system. There are going to be two Ransome B4 venturi burners on the chimney side.

Yesterday I completed layer 7, today - I am taking the day off.

I am picking up the building of the kiln in mid-process. I hope to show the design and construction from the start, but if I try to do that here and now...well, it just won't get done. So we start at layer 5 for now and the rest will come...really.

Layer 5 is a header course where the bricks go cross ways. The purpose of doing this is to add stability to the wall. I struggled to get this level as the hard brick on the inside isn't exactly the same height as the Insulating Fire Brick on the outside. I am also fighting a bit of a sag in the middle of the left side wall. It is not big, but enough to bug me.



The next layer, 6, has the ports for adding the soda/salt. I am planning on using a sprayer and with the soda ash and/or salt dissolved. The ports are 3" x 3". The original design had ports only on one side of the firebox, but I decided to add them to both sides to give me a little more ability to get the glazing uniform.

Here in the country, we do not have the hustle and bustle of the city. I do not miss the traffic jams on I59 or I10 in Houston at all. Or the pace of always having to be on the move and doing something that the urban life seems to foster.

But we do have severe air traffic control problems! The landings and take offs from the "airport" on the porch are frequent and chaotic. We have two feeders and get gatherings of 18 to 20 birds in the dawn and sunset hours - rush hour traffic! The birds are fearless. I can stand out by the feeders and they will come within arms reach, hover and look at me like "and what do you think you are doing here?"

This blog has been sleeping for a long, long time. No excuses. Just haven't been posting. However, I think that it is time to wake up the sleepy head and reconnect with the world. I guess my river buddy and glass artist Ellen has inspired me. I will try to post more often.

A good deal has changed since the last post. I am no longer studying at the Appalachian Center for Craft and have been building my own studio. The studio is located at our home on Puckett Point Road in Smithville, TN. It has taken a while, but the studio is operational and I have been throwing, firing bisque and glazing. For glaze firing I have been working with my friends at Creek Bend Pottery and doing wood-fire, salt glazed ware. If you are interested in the process of wood firing and salt glazing, please see the blog Firing@CreekBend Pottery.

Just recently I did an oxidation firing in my Cress E27. While this firing range isn't my first love, I think I will do some ware this way. Below is a picture of a pitcher from that firing.