Ashes for combustion tube insulation.

Hi, first time on this forum. Has anyone used wood ashes as the insulator between the double wall combustion pipe? Ash is a great insulator, and free. The main reason for my interest is my father-in-law and I are setting up a temp. outdoor RMH. An ash filled double wall pipe would be easier to take apart and dump around the compost pile.

Thank you!

I've seen several youtube videos of it being insulated that way. Not quite as efficient but certainly would work. It seems that those that use the rocket stove for temp, outdoor stuff use ashes all the time. The only reason not to use them is the better insulating properties of perlite/vermiculite, etc.

On a Mass stove. Where are the ashes going? There have got to be ashes left over. Is there a clean out somewhere? I seem to be missing that poing in information about building one.
Thanks

Jeremiah wales wrote:On a Mass stove. Where are the ashes going? There have got to be ashes left over. Is there a clean out somewhere? I seem to be missing that poing in information about building one.
Thanks

the ashes are cleaned out just below the wood feed; normally people just scoop the ashes out or use a shopvac type setup. otherwise I'm sure you could build a tray. there is also another cleanout just after the barrel where the exhaust gases exit. that way you can clean out the ashes that may fall down the sides of the riser. Basically build the RMH with the idea of having to clean it regularly because ashes will accumulate.

What the OP was asking is if you can use ashes for insulation around the heat riser; which the answer is yes, you can use them to insulate the heat riser, although it is certainly not preferred for long-term use.