Nice clean looking burn you had there Matt , 100% wrap insulation on the outer barrel it will increase the conversion time so much and the fuel used down below will be way less as well , , and as always well done mate .
Dave
11 Likes
right. How hot does the outside get? fiberglass might melt, and how do you keep it dry.
4 Likes
I’m not sure how hot Matts build would get , but the Hookway styled one’s i made got real hot , mine were in a made from a 55 gallon drum with a central pipe from bottom to top and sat on the ground with a trench dug underneath where i would use all the leaf litter and bark from my gum tree’s so i was not using any wood really , once insulated it didnt take long before it was self igniting .
For insulation i used just normal batt material eg: Rockwool , or over here its now changed to something called Earthwool , yes it does melt and go hard like glass if left exposed on the outside , but if you cover it in a layer of sheet steel or use another 55 gallon drum with top and bottom cut out and then split in half and wired hard against the rockwool it works real good .
Dave
12 Likes
It can go into melt down if you are not very carefull. The fiber glass will hold up better than the steel. You are not going to melt house insulation at steel melting temps.
3 Likes
Fiberglass melts at 1,300F (704C). Mineral wool melts at 2,150 (1176C) Steel is around 2500F (1371C). If there was a slightly larger gap between the barrels, then you could get away with like cement/perlite recipe used for kilns on the inside which would be perfect because you could just put the lid on it to keep the rain out. BUT it would be hard to pour and fairly thin so I don’t know how well it would hold up.
5 Likes
I dont know; pay attention and dont break it. There is nothing wrong with it so dont fix it. Im sure house insuation will work just fine.
4 Likes
Yes that is all i used was house insulation , i found a few old photo’s of a retort i built for Brian a year after his stroke he loved getting all covered in charcoal 
Dave
12 Likes
OMG!- trailer park boys!
3 Likes
Gonna have ta tell Brian you called him bubbles, he’s gonna love you .
Dave
5 Likes