LR Adkins
Well-Known Member
I apologize for not getting this up sooner. It seems several people are building HT ovens right now and could benefit from any info they can get. I said I would show how I did this awhile back but it has been slow going. The wife has kept me busy landscaping our new house. Planting the garden has taken forever. Yada, Yada , yada, anyway I haven't had much time to devote to the shop.
Ok, I started with and old kiln I had laying around for years. I played around with it for awhile trying to figure out a way to use it without tearing it apart. I turned it on it's side and it collapsed dumping the firebrick on the floor breaking several bricks and both heating coils. Project over!! Not really, I had another larger kiln waiting to come to the rescue.
I carefully disassembled the kiln, starting with the lid first to get it out of the way so I could get to the heating coils. The heating coils had been used one time since being replaced in this kiln so I wanted to use them instead of spending money on new ones.
Heating coils are a pain to remove without breaking them. You have to heat them and remove them while they are hot because they get very brittle after they have been red hot, just like a knife blade after heat treating.
I removed the control box from the kiln so I could get to the wires to disconnect them. Where the heating coils come through the wall of the kiln they are twisted around the bolts they are connected to. They have to be straightened before you can pull them through the kiln wall. I used a small propane torch to heat the bent end of the heating coils and while they were red hot I straightened them. Next I went to the inside of the kiln and heated about the first foot long section of the coil and while it was hot I gently pulled it through the hole and gently removed the 1 foot section I heated from the groove in the firebrick. Again I heated about a foot of coil and gently removed the coil from the groove in the firebrick. I continued to do this until the heating coil was removed from the grooves in the firebrick.I didn't get many pictures of this because I was too busy playing with hot stuff.
First pics is showing where I started on the outside with the end of the heating coil. Second pics shows what happens if you don't heat the coils. I broke one.
Ok, I started with and old kiln I had laying around for years. I played around with it for awhile trying to figure out a way to use it without tearing it apart. I turned it on it's side and it collapsed dumping the firebrick on the floor breaking several bricks and both heating coils. Project over!! Not really, I had another larger kiln waiting to come to the rescue.
I carefully disassembled the kiln, starting with the lid first to get it out of the way so I could get to the heating coils. The heating coils had been used one time since being replaced in this kiln so I wanted to use them instead of spending money on new ones.
Heating coils are a pain to remove without breaking them. You have to heat them and remove them while they are hot because they get very brittle after they have been red hot, just like a knife blade after heat treating.
I removed the control box from the kiln so I could get to the wires to disconnect them. Where the heating coils come through the wall of the kiln they are twisted around the bolts they are connected to. They have to be straightened before you can pull them through the kiln wall. I used a small propane torch to heat the bent end of the heating coils and while they were red hot I straightened them. Next I went to the inside of the kiln and heated about the first foot long section of the coil and while it was hot I gently pulled it through the hole and gently removed the 1 foot section I heated from the groove in the firebrick. Again I heated about a foot of coil and gently removed the coil from the groove in the firebrick. I continued to do this until the heating coil was removed from the grooves in the firebrick.I didn't get many pictures of this because I was too busy playing with hot stuff.
First pics is showing where I started on the outside with the end of the heating coil. Second pics shows what happens if you don't heat the coils. I broke one.