Size of kiln

[Chris Lowry]

I'm trying to pick a new kiln but don't know anything. When slumping/fusing how much room should you leave between work and edge of kiln? When kiln casting how much room between mold and kiln?

Thanks

[Marty]

First- Don't give up on Pete VDL (craftweb), he gets cranky sometimes (like the rest of us). The problem is that you're asking too big a question. What do you want the kiln for? In the perfect studio you'd have all the kilns you could ever dream of needing- have you got the space and the budget?

[Chris Lowry]

Ok I think I have to narrow it down. I really want to take blown parts, fuse them together and slump them into a shape. I know there is a ton to learn but first get a kiln. No I don't have much room but that will have to work itself out. I don't want to invest all my money but I don't want money to be the deciding factor.

What I don't understand is if I want to make a 23" platter can I put it in a 24" kiln. Is it ok to have your work right up to the edges of the kiln or do you need some space?

The even heat studio pro 24"x24" looks good to me. Big enough to do a lot of stuff but not too big when doing smaller things.

[Marty]

In my top fired rectangular kilns there are triangular-shaped cold spots in the corners. I can go right up to the front and back sides though unless the schedule is finicky. For a full fuse held long enough or for a long slow slump I can cram stuff in and expect uniformity of results.
In side fired kilns the edges will get hotter than the center faster so you'd have to compensate with your schedule and possibly by baffling the edges.

I'm not fond of EH for various reasons but others love their kilns.

[Chris Lowry]

Thanks, that makes sense. It's more about even heating than size.

Just curious, what are you found of in the 24" range?

[Marty]

I like Paragon's GL series. More $ though.

[Chris Lowry]

Ok I've got to ask, why do you like those? Is it just size or material?

[Marty]

Construction, mostly. I think EH skimps on insulation and I'm not fond of their hardware, or their element grooves either.
Their customer service too.
I've built my big kilns but bought a couple of GL24s for my new studio (after using them extensively at Corning).

[Chris Lowry]

Ok now I'm totally lost, that kiln is a front loading kiln with no elements on the top. I thought that for fusing you really wanted elements on the top. Plus it seems like the front loading would be harder to use. When you said you had trouble in the corners of the oven was it in these Gl24s? For that reason is a round kiln better?

I do understand what you mean about having better material, always best to do it right the first time.

Sorry I have so many questions, I'm just going for it.

[Marty]

The pair I got have elements everywhere but the floor. If you're casting, you'll want them there as well. Ideally you control the elements individually depending on what you're doing in the kiln.
Front vs top vs bell (or clam): each has plusses and minuses.

Re the ones I built- it's a lot easier to build a rectangular kiln and just stay out of the corners (if they turn out cold) than to build a round or oval one. Mine measure 31"x81"x14"d and 28"x 58"x11"d. Brick sides and floor, fiberboard top.

I recommend buying Henry Halem's Glass Notes- he's got a lot of good info on equipment, including building your own. My biggest kiln cost me about $1500 in materials, another $500 for the controller.

[Bert Weiss]

Brick kiln walls suck heat on the heatup and release heat during the cool down. Consequently, this creates uneven heat inside the kiln. I work in large kilns, and I leave 3" between where I put glass and the kiln walls. I know there are people who get away with placing glass very close to kiln walls. I am not comfortable with this. In a small kiln, I would never go closer than an inch, and I would prefer 2".

[Terry Crider]

Marty,
Has your fiber board top got a name I can google ?
Thanks

[Marty]

Unifrax? I don't remember what density, Bert will know.

[Bert Weiss]

The board you want by any manufacturer is designated HD for High Density. LD, low density will dent or fall apart too easily. Some companies make MD medium density.

Chinese boards I just used cost about half as much as Unifrax. When I bought Chinese LD boards that cost about ⅓ as much as Unifrax they were totally bad quality and not worth a nickel. Those were from McGills. I won't be shopping there any time soon.

[Buttercup]

This is the product I've used for shelves and also for the lid of a brick kiln.

http://www.morganthermalceramics.com/pr ... d-products

Jen

[Marty]

The problem is the max. available size: "Ceraboard 100 and Ceraboard 115 are available in 1200 x 1000mm panels".
I'm looking for a replacement for the Dyson shelves that showed so much promise (at great cost) and then broke apart.
24"x48", 30"x60 and larger.

[Bert Weiss]

http://www.ceramaterials.com/ceramicfiberboards.html This company sells only by the case. The second set down are the HD boards. These are Chinese boards and cost about half as much as Unifrax Duraboard HD. You might find a local refractory supplier who will sell you a single board. These are dotted all over. I know the ones in New England.

[Bert Weiss]

The problem is the max. available size: "Ceraboard 100 and Ceraboard 115 are available in 1200 x 1000mm panels".
I'm looking for a replacement for the Dyson shelves that showed so much promise (at great cost) and then broke apart.
24"x48", 30"x60 and larger.

Marty

call ceramaterials http://www.ceramaterials.com/ceramicfiberboards.html They have a source that can fabricate custom sizes. I'm not sure, but 30" x 60" might be a possibility, They have a grade called SHD super high density. I just did a 3" thick floor with 3 panels shiplapped. We also got glue and caulk. The first firing will be with the glue. Then I'll caulk the seam and sand it smooth. I am clueless as to how long this will last. I have 2 sources for a one piece thin smooth flat veneer that can be set in place and never moved. They are expensive. One is Zircar, the other Smart Ceramics in Woburn MA.