Dale Schlehuber

Will I have to worry about "klinkers" with a rocket stove?

Thank you for the information about the riser. If the metal is not long term, why do all the videos show a 6" pipe insulated with clay and vermiculite and a 10" pipe? Could have saved some money not buying an insulated stove pipe and just built up the fire bricks!

If the feed, burn and riser are all made of fire brick, do I have to worry about the extra heat of coal, and just have to worry about getting adequate oxygen for the burn?

Thanks Ernie (not Eric, sorry about that!)

Do I understand correctly, a grate? As in the bottom portion of the feed chamber, to hold it off the bottom? Will the increased heat also effect the riser metal?

I have seen the drawing, but unfortuneately I am unable to enlarge it to see what dimensions and writings there are. Thanks for the idea. We have got the stove part working great once I found erica and eric's formula under the engineering section.

Jay,

thank you so much for your input. It is especially nice to know about the recycling baling twine.

I understand the part about different gumbos. That in Texas is way different than ours in Montana. My next step before adding the mass to the stove is to do the quart jar test, allowing the sand to settle first, then the silt, and last the clay and find out what percentages I have in our test sample.

BTW, CSA = Cross Sectional Area, which should be about equal from intake, to burn chamber, to riser. The riser being 6", pi x r (2) = 28.4, so we had to make the intake and burn chamber about 4.5 x 6 inches. When we did, boy did it "rocket"! Also, discovered the length of the intake and length of burn chamber has to be less than the length of the riser. We are now going to have to experiment a bit to find out what it will take to burn coal, as my friend has a seam that the original homesteaders used to keep warm in winter. The increased heat may mean that the riser will have to be built out of fire brick to keep the riser from melting!

Not planning on making any earthenware, was just curious if anyone had, especially from our area. Never hear of anyone doing it, so volcanic ash content may be too high/low.

Thanks again for your response. Would love to meet you if you make it out to Montana. Unfortuneately we have few trees for an arborist to look at! But there are lots of prairie dogs to act as targets. Figure an ex-Marine might enjoy that.

Why would the dimensions be different? Longer burn chamber? Would the intake require more oxygen because of the increased heat? If so, any idea what the variants are?

We are building a RMH on my friends ranch in SE Montana. Lots of cactus and some sagebrush, just a little wood in the creek bottom. However, he has a 3 foot seam of coal on the ranch that the original homesteaders used to heat their houses. Question is, will the coal burn (much hotter I assume) be a way for him to warm his buns? Any forseeable problems in so doing?

Anyone every been stuck in mud? Not like the "gumbo" mud of South Eastern Montana I will bet. Anyway, my question is this:

1. can I use the gumbo (bentonite?) to use as the clay part of cob? True bentonite is volcanic ash of 100 million years ago that has gone through some chemical processes of pressure and time to become the material of drilling mud. True clay is a sedimentary material laid down in ancient oceans.

2. Has anyone made cob from gumbo? In constructing our rocket mass stove heater for my friends 100+ year old homestead last weekend we mixed some gumbo and sand 1:1 ratio. It seemed grainy, not smooth like pottery clay, but held together. We didn't add straw as we only wanted to plug up leaks to test our stove (several times as we didn't have the correct CSA, which we found here later in the forums).

3. Anyone ever try firing the gumbo clay for pottery type purposes?

4. A little off topic, but has anyone tried using old bailing twine instead of straw in the cob? We didn't want to use this next to the rocket stove where it might melt, but were considering "recycling" the piles of used twine on his ranch for the mass in the heater portion of the stove.

We are attempting our first rocket stove (and mass heater) this weekend and have tried many variations but still have trouble with smoke (and flame) coming from the feed. Initial paper start fire is really rocket sounding, but as the sticks are added, the sound isn't there, and eventually flames and smoke start coming up the feed side.

Here is what we have:
6" x 33" double insulated pipe that has been filled with vermiculite and clay
firebricks, clay, sand, regular bricks found in alley.
pre-burned 20 gallon barrel

Questions: 1) is there an ideal burn chamber length? too short, long, or tall? (ratio to the size of the pipe?)
2) is there a limit as to how high the feed chamber can be?
3) is there an ideal ratio of the size of the feed chamber to the upright pipe (6")