Time to update this project again. Got married at the end of June and didn't have much free time. Got a few days away from work this week and was able to head back to my parents' place to work on the fridge.
Thursday morning was mostly planning. We stopped at Norfolk Iron and Metal to pick up a 16 gauge 12' by 4' sheet of metal (120 lbs worth - this fridge will be heavy by the time it is all done). Also stopped by Menard's to pick up 3" gas exhaust pipe that we'll use to control airflow. Thursday afternoon we took the piece of metal over to a friend of my dad that has a plasma cutter. That works really slick to cut all pieces for the fridge. We also cut 6 racks of expanded metal for my grates. Thursday evening I took the cooking chamber into my buddies' auto body shop to have it sandblasted quick to make sure all the paint on the inside was gone. By the time I left there had drank too much to do any more work...so I went to a field test plot party.
Friday was the big day. Started from the bottom of the fridge and worked to the top...so my dad and I fabricated the firebox. First is a series of pics prior to starting. First is a pic from the back of the fridge where I'll put the firebox. Took the torch and cut out off the middle crap at the bottom there. Also removed all insulation that was in prior. Don't know what it was, but we trashed it in the burn hole.
Getting the metal in place took a while. Had to torch holes in the back to make it fix. We put in two sheets all the way across bottom. In between will be insulation (this way if I put it on a deck, hopefully it will have some protection from starting it on fire). The sides are also insulated (easier to see from the picture in the back). Also, between the two sheets are 2 4 inch tall square tubes for support of the firebox. Since this was taller than the front lip, we had to cut a new metal piece to close up the front.
Next my dad welded the firebox together. You can't see it in the pics, but the expanded metal is sitting on 1 inch angle iron so the ashes will fall through. The back of the firebox has the sheet metal also up an inch so if i drag the box out, it won't pull the ashes with it. Plan will be to use to latches, one on each side to bring the bottom door close. Will need to get some fiberglass rope to create an air tight seal. I wanted separate doors for the firebox and cooking chamber. I'll have 3 - 3 inch tubes with dampers going from the firebox to the cooking chamber. This way I can close the cooking chamber up from an ash if I need to fill back up the firebox with charcoal (shouldn't need to since it 24" by 13" and 5"-6" tall...that's alot of charcoal power for an insulated fridge I think.
The last pic is of the back of the fridge where we have closed up the back of the firebox.
This got us to the end of Friday when I needed to pack up and head back to Omaha. Hope to make it back during Labor day weekend to finish it up. We have the angle iron ready to be cut for the support of the expanded metal racks. We have the hole for the chimney cut out on the top of the fridge. Need to cut the hole for the chimney out of the top of the cooking chamber. Also need to cut the holes from the firebox to the cooking chamber. Will need to insulate and the chamber and close it all up. Then it will be ready for a test run.
Found today in my running around Omaha the Rutland high temp food grade silicon at Ace's. Just need to find some fiberglass rope at a decent price.
I'm still considering a housing case for my remote thermometers. I'm debating using the inch hole in the back of the fridge to run the lines and covering them with some type of cork...but I'm thinking it will be easier just to run the cables through the door under the fiberglass rope. Let me know if you have any thoughts.