DVC500 at last wrote:...
Ash was rather high, I think. 17# with most of that wieght from bone. (is this normal???)
Completely white ash, but lots of bone.
Around April/May '09, I figured out why the ash content was so heavy. Normally, coal gets pushed from the bottom of the bin, to the bottom of the burn pot. Between the back sides of the pot and the front of the firebrick on both sides, are two 3/4" cracks or open spaces. Some(alot) of unburnt coal was falling out of the crack and down into the ash bucket before it ever reached the burnpot!
So I decided to take some accurate measurements of those open cracks, and see if I could cut some firebrick to fill them up. As it turned out, it was easy to cut the firebrick with my wet tile saw, and a 5" grinder. The two pieces of firebrick are held in place by Furnace Cement. Before I installed the pieces, I covered the burn pot with tin foil to prevent the furnace cement from sticking to it. Once the furnace cement was dry, I pulled the brick back out and put them in the oven to cure the cement, and I removed the tin foil at this time.
Note from the pictures below, I had previously 'glued' all three firebricks together, as the two bricks on the outside kept falling off the ledge in the stove. So now, all three firebricks and the two pieces to fill the cracks, are all one piece, glued together with Furnace Cement. FYI... this large solid piece of brick is still completely removeable from the stove, for easy cleaning.
I will re-test the stove for efficientcy, with the same coal I used previously. I'll post the results in this thread.