Dan Stolarczyk

I would love to hear your suggestions on cutting a propane tank as I think others would also
Danford1

Thank you. Just looking at the picture I couldn't picture the exhaust. Now that I know it has two tubes, I don't need any more picts.
Why two tubes for the exhaust?
I'm curious, I'm still learning about rocket heaters...
Danford1

I have a garage that is divided in two with a wall. I want to build a 6" Rocket Heater (no mass, just the heater)
that has the burn chamber on one side of the wall and a 100 lb propane tank radiator on the other side of the wall.
I want to keep open flames out of heated side of garage as some times I spray paint in there...

The J tube burn chamber would need to be pretty long, say 24" between back of fuel area and front edge of riser tube.
That means the total bottom edge of J tube is 36" long from the front of fuel area to the back of riser.
I would of course have fire bricks insulating it where it goes thru the wall.
I plan to make a wood pellet dispenser system to use on it.

How long is too long for a burn chamber?

Dan

Can you post a few more pictures showing your exhaust system?
Thanks
Danford1

Have you thought of adding a secondary air inlet along the top of your firebox? That helps add a vortex and increases heat production (from what I have read, I haven't tried it).

What temps are you getting on top of the tank and on the exhaust?
You can add some fins to the tank to help dissipate heat.

Danford1

Please post a few pictures.
Thanks
Danford1

Exactly. In a mass heater you want the exhaust to have heat for the mass. With just a heater, we want as much heat as possible drawn off and radiated to the room.
I also thought of pipes say 1" in diameter running thru the bell above the riser. The pipes would be hollow and allow air to be drawn in and through them for heating the room. Perhaps even a low speed fan blowing thru the pipes.

Once I find time and scrap, I'll start building and experimenting. I just want more of a plan before I build. My spare time is very limited. Too many other projects going at once...
Danford1

Nice! Thanks. I read where before he added the fins he could get his top tank temp to 700 degrees, after the fins it was only 500 degrees. That is 200 degrees more heat radiated to the room.
That is what I was hoping for, more heat from smaller tanks. Plus the exhaust temp was reduced which verified more heat was going into the room.

I see from his design that he didn't make the burn chamber opening to the riser, smaller. I read where that portion should be a smaller dimension.
Also he didn't have any secondary air in the riser for the vortex.
From further reading, shouldn't his outside air intake be a bigger diameter? I like the way he incorporated that. To me it just seems like it should be At Least 4" not 3"...

I like most of his design and integration. My mind is already spinning thinking how to add a secondary air chamber inside the combustion chamber. That reduces the size of the opening into the riser and feeds heated secondary air in for the vortex. Some easier to use clean outs, pellet feeder system, more fins on tank, top flat plate on tank and on and on ... I'll do a Bunch more reading then combine design ideas and come up with something...

Danford1

Have things like this been tried before?
Adding heat dissipators or heat transfer fins to the side of the barrel.
Stacked doughnut rings or vertical plates etc.

Here are two sketches of what I mean. They could be horizontal or vertical or any combination in between.

Holes could be drilled in the fins to add edge surfaces for heat transfer to room.

I saw MANY pictures of RH but they all had a smooth type drum or barrel. I think it would make sense to add
more metal to dissipate the heat.
What are your thoughts and experiences?

Danford1

I have been reading about rocket stoves, heater and mass heater for days now.
I haven't built anything yet. I have ideas I want to try but
figured other people already tried them so I'll ask here.

Lets say I build a rocket heater and use a 30 gallon drum over the riser tube.
I understand that the drum will get hot and heat the room somewhat.
Has anybody added side fins on the drum to help dissipate heat?
How about putting a big thick plate on top of the drum that is bigger in diameter than the drum?
I remember seeing years ago these fins that wrapped around the flue pipe on an old time wood stove. The fins help add heat to the room.
I can picture a drum full of plates, fins etc to really draw the heat off the drum.

What has been tried?
Are there any pictures of the devices?
How did it work out?

This would be for regular heaters, not mass heaters...

Thanks
Danford1