Car Kiln Design

[ltaub]

Hi, I see references to car kilns in some discussions here, and am wondering if anyone has a basic car kiln design they can share.

Thank you!

 

[Bill Kielb]

Just asking, do you mean an actual car kiln where the wares are wheeled in and usually fairly large say 9 - 20 cu ft and even larger? Sort of like the picture below:

 

 

[ltaub]

Hi Bill, exactly. But we'd like to build a smaller version of this concept.

 

[neilestrick]

The car design is doable at any size, but it is generally reserved for large kilns that would be difficult to load otherwise. It's a lot of work, so a small kiln may not be worth the effort unless you have a specific need for it. Lots of welding, and lots of metal that will greatly increase the cost of the kiln.

Some specifics:

Easiest to do with two power burners coming in from the back. You can do it with bottom-mounted venturi burners, but it's a lot of stuff under the kiln with the car.

If you look at the platform, there's a wider section at the bottom that goes under the bottom row of bricks in the main body, and a raised portion in the middle that just fits inside the bottom row. This provides a decent seal.

The track is just two pieces of angle iron with the angle pointing upward, and the wheels of the car are grooved to run along the track.

Beyond that you could engineer it yourself pretty easily based on the picture above.

[Mark C.]

I have built two of them. My current one (35 cubic stacking) 3 12x24 shelves on car-about 5 feet high

I have seen a bunch as well. The best and most are made from a basic plan called the Minnisota flat top-which the plans are in an old studio potter and a few kiln books.If I recall Nils Lou designed them

I have a sprung arch not flat top. People alter this plan a bunch but all seem to keep the floor and car design which is tapered plug shop car. I like 4 burners two on a side with bag walls so I have made two that way. I do not like power burners so I use natural draft burners as well.

I have a friend with a 27 cubic Geil and thats about as small as you would want to make one as they are made for easy of loading and smaller is better to have front loader

 

[neilestrick]

4 minutes ago, Mark C. said:

The best and most are made from a basic plan called the Minnisota flat top-which the plans are in an old studio potter and a few kiln books.If I recall Nils Lou designed them

In my opinion, the flat top design is more work than an arch and less durable. I think the flat top was designed for people that are afraid to do an arch, or just don't understand the physics of arches. I've seen them done two ways- one using rod threaded through the bricks, and one that just uses compression at the corners. I don't know what the size limit would be on the compression-only method, if any. The threaded rod method is a ton of work and a big mess what with drilling holes in all the bricks. 

I used a compression-type flat top design on my large top loading electric kiln and it worked very well, but an arch was not possible on that kiln and it only had to span about 30 inches of open space.

[Mark C.]

I do not like the flat tops (the top of kiln is flat) the arch is the way to go for sure. The car design is a solid one on that -I should have spelled that out clearer.

Use thick angle  iron for the uprights and a for arch support . The car  design has worked well for 45 years for me. The side burners and back walls as well.. You just need to tweek the design a bit to improve it. And it does need some improvements as Neil pointed out

[ltaub]

Thanks Mark, Neil, and Bill. The resources and information you share are quite helpful. I appreciate your knowledge sharing.