Woodshop Barrel Rocket heater

Good day to all. Let me first introduce myselft since I am new to the forum. My name is Elvis Halilovic and I come from Slovenia.

This year I finished a project called the floating city on a lake in my hometown of Velenje, you can see some pictures of that here, Floating city
It's supposed to be a self sufficient floating modular platform, but for now it's in the first stage, from the the supposed finished setup. It has a greenhouse, composting toilet, water purification system and a holey rocket stove. Still missing wind turbines rocket stove heaters and a few other details.

I am allso a woodworker and since winter is closing in I am going to need sufficient heat for my workshop. I have a sawdust rocket type burner, but that isn't enough since most of my wood comes planed,
hence I do not have enough sawdust to keep me trough winter, while scrap wood is abundant.

I've drawn a simple plan just to ask if my proposition would work. The idea is, that the horizontal feed would have an air gap on the bottom that can be regulated in order to provide air to the fire,
instead of the clasical side burn. The reason why I don't want to use the top feed system is because a lot of my scrap is tiny pieces and my idea is they would just clog up the air intake. Just
my thougts, please correct me if I'm wrong.

All the dimensions of the tubing, is more or less guesswork accordng to what is at hand to work with, I can't seem to be able to find any formulas regarding cross section sizing etc.

Any information and suggestions are wellcome.

Thank you!

Elvis

Elvis,

you might want to consider a pocket rockets like the one in the picture below. For the proportion, the Rocket Mass Heater book does not give a definitive measurement. I know that for the big one on the right of the picture, Ernie and Erica Wisner recommend that the feed tube be 3-4 in from the bottom.

Adrien, thank you for your reply.

Today I got my barrels, and the temperature plumeted below 0°C, getting cold, so I'm really keen on making one.

I haven't seen the pocket rocket design before, what are the differences between a regular rocket stove design and this one, except that this one is probably easier to make?

If I understand correctly, you just stack the wood in the feed tube that must be 3 to 4 inches from the bottom, and the chimney is just put on top of the barrel and that takes care of

the draft? Does it need any insulation for the burn or nothing?

I really appreciate your help!

Elvis

Elvis,

the rocket pocket is not as efficient as a RMH, but it is much easier and faster to build. There is no insulation to it. The wood burns at the bottom and the chimney creates the up draft. This picture shows another design.



If you build one in your workshop, be aware that the bottom of the barrel gets really warm (see other picture) and, unless you have a dirt floor, you will want to put something fire resistant under the barrel.

Thank you for the help!

A pocket rocket is a good temporary fix for my needs. I used a 60l barrel, and put some steel legs underneath to raise it about 50cm. The workshop is warm enough to work in
comfortably. In the morning just to get the place up to temperature I ad a small fan to blow the air around, and it helps a great deal.

But when testing a lot of the heat still goes out trough the chimney. Would fins welded to the outside of the barrel help radiate heat, and hopefully reduce some of the heat
goung out?

Even my father, sceptic at first, concluded that this should be in his garage, so that's a major sucess!

Thank you again,

Elvis!

Do you have any pictures?

Heat going out the chimney is definitely an issue with pocket rockets. I am not sure that fins would help that much, in fact I would be concerned that they might reduce the temperature in the chimney and thus the updraft.

One way that I heard could make the pocket rocket better is to add a mass close by. This mass would take in the heat while the fire is on and radiate afterwards.

Well, for more heat heat transfer to the actual room, i think you could do a bell. Tho, i don't know if a pocket rocket could push enough to get the gases through. Something like a big barrel above your 60l one, the exhaust pipe of the pocket rocket you have now entering it at the top, and another pipe exiting at the bottom, going to the actual chimney tube you're using. Does that make sense? Not a pure bell, but along the lines. Normaly for a proper bell, you have something like 3x the diameter of the pipe you're using, and something like inlet 5cm above outlet, the lowest possible.

Winter is here, yesterday we got some snow and temperatures plumeted. I reliased that my 60l pocket rocket is not enough to heat my workshop sufficiently, since it is quite a
big space. 6x8m and about 2m high. I tried everything, with the fan and all but still not enough, and the wood I have for scraps (small chunks) is not particularly suited for this type of stove, since it clogs up everything after a while. Adding mass to the stove...

I'm posting a picture of the stove, the legs allthough look flimsy are in fact strong and safe.

In the next picture I'm adding a stove that my father built from tire rims welded together, it's a regular
type stove but because of the large surface area it generates a greater amount of heat than the pocket rocket. It's situated In the next workshop 6x5m in size, and it heats well enough to work in. The main drawback in this
type of stove is the huge amounts of smoke it generates.

So now I'm thinking of merging a rocket type heater and using wheel rims instead of a barrel? Does anybody have any info how will a stove like that behaves since it does not have any single flat surfaces?


Thank you for the help!

Elvis Halilovic : I really don't know that to think, traditionally we are trying to get the hot gases to form into a toroid, or doughnut shape, as it leaves the heat riser at the top and channels between the exterior of the heat riser and the interior of a drum.

Keeping it simple I would suggest leaving a drum top for the upper 1/2 and then use the wheels. That would increase the surface area for radiation but would also lower the temp at which it (compared to a barrel of the same height) would radiate heat at ! I think you would do just as well with a higher heat riser and matching barrel!

If you want to try this I would make one change at a time and remember to protect your Cross Sectional Area C.S.A. ! g'LUCK ! , - Pyro-maticly yours Allen L.