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Chris Throws Pots

Member Since 27 Jun 2012
Offline Last Active Nov 05 2014 01:25 PM
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Posts I've Made

In Topic: Wood-Fired Turbo Kiln

28 August 2014 - 07:07 AM

Seasoned Warrior,

I have the good fortune to be able to fire a wood burning kiln a few times a year. We make cone 10-12 in the span of a day. Like has been wisely mentioned previously in the thread, just because it's not anagama, it doesn't mean it's not legitimate woodfiring. The design of this kiln is called the Phoenix Kiln, named for the Phoenix Workshops of Dunbarton, NH in the late 70s. There's an old issue of the Studio Potter (Vol 7 No 2) that describes it, and it's also discussed in the book Wood-fired Ceramics: Contemporary Practices. It's a small spring arch cross draft that climbs quickly. The placement of the firebox beneath the ware chamber is key. As the flame travels beneath the ware chamber it heats the floor of this section, gaining ambient heat before the flame comes into direct contact with the ware. Also, unlike in an anagama or norigama, there is no struggling with the cool ground. The pots are up off the ground so the pots and chamber heat very evenly.

We use rough ends from the lumber mill that we purchase by the bundle and cut down to the right lengths. We use about a three quarters of a cord to a cord and a quarter per firing depending on how long the wood's been drying, how tight the load is, etc. Admittedly there is not the level of ash buildup you'd see in a more traditional 2 or 3 or 4 day firing, so we also salt at cone 10 to supplement. We get great results.

The kiln was built in southern Vermont about 10 or 12 years ago, and after being relocated a number of times via crane and flatbed truck, the kiln's owner had the genius/insane idea to put the kiln on a trailer. So for the last few years it has been on a 20' heavy duty trailer. The kiln and trailer weigh about 10 tons total. With about a week's notice (and a large enough truck to haul it) we can take down the flue, support the arch with a form and drive to somewhere new to set it back up to demo or workshop. It's an ordeal to move, but pretty straightforward. The last time we moved the kiln was to it's current home in Burlington, Vermont's south end where the kiln's owner and I run a weekend workshop a couple times a year.

As you look to faster woodfiring methods, check out the Phoenix Kiln. It might be a good fit for what you're looking for.

C

In Topic: Is Kiln Wash Necessary?

04 August 2014 - 08:59 AM

Nicolesy,

 

I run a community clay studio, and in this arena kiln wash is a must. The problem is that given the frequency of our firings, our shelves warp quickly. I'd like to flip our shelves every 2 months to combat the warping, but grinding off the kiln wash leaves them with less-than-flat surfaces. So essentially I'd be trading warping issues for surface craters. And if the shelves aren't ground down pre-flip, the kiln wash flakes, glaze drips, etc will fall into the pots below. I'm between a rock and a hard place, and end up dealing with warped shelves until it's bad enough I just need to buy new ones for the studio.

 

I have a few shelves for my own personal use which I've skipped the kiln wash and have marked the sides A and B with iron oxide wash. I keep a log and alternate which side is fired facing up. When I get my own kiln, this is how I will fire. No kiln wash on the majority of shelves, alternating the sides to prevent wapring. I will keep a couple with wash for glaze tests, etc.

 

If you know your glazes, keep a log of firing times to predict element health, and are mindful of your relays, my opinion is that it's worth the risks of firing sans wash. And I'd encourage flipping them regularly. Certainly all mishaps can't be avoided, but the more exact your practices can be (and it sounds like you have pretty exact practices) the better risk management you'll have.

 

Good luck and congrats on the new kiln!

 

C


In Topic: Galley On Pot Or Flange On Lid..

22 July 2014 - 01:06 PM

Like others have wisely mentioned already in the thread, function should dictate the form of the lid.

 

The Val Cushing Handbook has a great section on lids. There are drawings of all sorts of different shapes, do's and don'ts, critical mistakes, tips, etc. When teaching lids to my students I'll share these pages and frame the discussion around function, then over the course of a couple weeks cover (no pun intended) 5 lids:

- Basic Flange "The Hat" thrown upside down

- Basic Gallery "The Bowl" thrown upside down

- Flange + Gallery w/Inset Knob thrown rightside up

- Flange + Gallery w/Attached Knob thrown upside down

- The Russian Doll thrown as a closed form then trimmed gallery and flange

So many lids, so little time.

 

Someone also brought up firing lids atop their corresponding jar/teapot versus firing them separately. I'm all for firing lids along with their corresonding piece. Where the clay is going to experience change and movement as it shrinks, I want the set to experience all this change together as one piece.

 

My two cents.

 

C


In Topic: How This Surface Was Created

08 July 2014 - 01:31 PM

I'm in camp fluting. I have a mirror in my house (thrown with the intent to be a platter, but it cracked as it dried) that has a very similar look. I produced the marks with the rounded end of a Kemper trimming tool.


In Topic: Requirements For Good, Basic Studio

07 July 2014 - 11:34 AM

TA,

 

Congrats on your studio! In my opinion, the most important requirement for any studio is something that can't be bought. It's also something that can be very challenging to keep up with. It's a diligent committment to cleanliness and heath/safety practices. Especially in a private studio, where your decisions and actions only really impact yourself, it can be easy to get lazy about this stuff.

 

Scrub and sand outside.

Lift with your legs.

Good posture at the wheel

Replace your respirator cartridges when they're due.

Vacuum often.

No brooms.

 

It's easy to say you'll follow the rules. It's harder to follow through and hold yourself accountable. It's something I struggle with and I can't imagine I'm alone. You're investing in your studio, take care of that investment by taking care of yourself.

 

C