Rocket surgery during the January thaw

Jan. 26 almost 50 DEGREES and SUNNY !!! What better time to be in the greenhouse / studio, fine tuning my rmh, its 75 out there and other than a short test fire after surgery no fire since yesterday eavning. When I rebuilt my core this spring I went with a very long burn tunnel , 18" roof on an 8" system ... I did get temps steady at 800+ F. on the barrel top, even went over the 1000 F mark a few times... but I wasn't getting the temps that I could get last season with a cast core and... a 9" burn tunnel roof. So.. Today in a mere 4 hour surgery I removed 5" from the roof of the burn tunnel, now I will see if I like a 13" roof better. With the longer tunnel I was getting excessive combustion ash left over, left unchecked it would have stalled the whole system. Test burn was only one charge of wood with sopping wet clay and it went exceedingly well. Waiting for this eavning to give it 4-5 hour burn to really dry out and heat up. I just had to try pushing the envelope a little... cause you know... if you don't try you'll never know if you can...

More; A sawsall was invaluable in cutting thru the cob. a putty knife for fine shaving and a rock chisel for the stubborn parts.

The test fire

How old is the system and how many times have you changed it ?

Two years old , this is the second change.