Greenhouse rocket...

[matt walker]

I've had good luck with those medium sized barrels, so probably no need to change it out unless you do a rebuild. If you can do a little build up where the riser sits and get some more riser height overall, from burn floor to riser top, you'll help the stove out a lot. You'll have to bring up the barrel as well, but I've had good luck just adding a cob ring to build height for the barrel base. If you can get 6"+ more riser height it will help a ton.

Your a bit thin on riser insulation as well, but it most likely wont affect performance unless you are doing real long burn sessions. Keep your eyes open for a small barrel, sometimes called a "grease drum" and pretty easy to find at big truck oil service shops. They make perfect insulation canisters for the riser. I've used them in the medium barrel like you have there and although its kinda tight it works well.

Awesome hoop house man. I've been an Eliot Coleman fan for a while now, but haven't implemented anything as in my climate I've got greens all year even outdoors with total neglect. Someday though. You're kinda giving me the bug right now.

[Mikimble]

Hey Matt,

In the rocket mass heater book, they say if using a round pipe for riser and sitting it on a sqaure set of bricks; to mud the corners (page 39). Should that be cob, clay/perlite, furnace cement or all/none of the above? Any ideas??

Mike

[pa_friendly_guy]

Your place looks pretty level for Fairmont, you must have lived there awhile. It seemed to me that all of the good flat land was bought up years ago and pasted down from generation to generation. Thanks for sharing your design and the link that explains the process. I was surprised that the 2" pipe would bend that much with out breaking. A lot of torque on those pipes. Are you happy with the head room inside? It looked pretty adequate to me, I am 6' tall and the link said the center would be about 6' 6" or so. That makes it OK to walk around inside and bend over as you work the beds.

[matt walker]

Well, I just love messing around with the darn things, so I'm inclined to just get after it with mud and see how long it lasts. My outdoor systems are, like, really low grade mud that I dig when I work on drainage. I don't worry about the make up too much. If you have some insulative material to mix in with it, that's always good next to the fire anywhere in the front end of the system.

So yeah, I guess my advice there is just mud it up and let 'er rip. Use mud to seal the outer barrel as well so it's a few second thing to pop it off and see what's going on inside. Once you've settled on a solid design you can work out longevity issues with materials, but for now, play with it with free materials. Or, that's what I would do anyway.

Wait, did I answer the question? Yes, mud and perlite if possible. Lol.

[Mikimble]

Hey Matt,
Thanks for the advice. Temps are going down here this weekend, so I need to get this going again. I went out at lunch and picked up some firplace mortar. The clay slip I had around the bricks/heat riser looks like if failed; so I may try the mortar. I am also going to try raising the barrel; my gap is probably only 2 inches or a little more at the top.

Mike

[Mikimble]

Hey,

With a setup like this, who needs paper to start it up??



Mike

[matt walker]

Wow, awesome. That looks like one of Lasse Holmes' designs. Is that in AK?

Adding that fireplace mortar to your existing clay will make a real durable mix. I'm sure that will do it.

[Mikimble]

Matt,

Here's the URL

Mike

[matt walker]

Thanks Mike. I thought it looked familiar. What an awesome stove.

[Mikimble]

Hey Matt,

You're welcome. I furnace cemented up the connection at the heat rise/burn tunnel, and that fixed the problem. No smoke, burning for about 8 hours now.

Mike