Fire coming out of feed tube on rocket stove

I have made the mock up of my rocket stove that I wish to install in my house. I fired it up and all the fire is just coming up the feed tube and not into the burn tunnel and heat riser.

The whole thing I made from new fire brick which I was able to purchase from a local supplier for $1.53 per full fire brick which I thought was a pretty good deal.

Anyhow the feed tube inside dimension would up being 7 1/2" x 7 1/2" The burn tunnel is slightly narrower at 7"x 7 1/2" and the heat riser is 7 1/2" x 7 1/2" inside dimension.

Any help would be greatly appreciated

Chris Layton wrote:I have made the mock up of my rocket stove that I wish to install in my house. I fired it up and all the fire is just coming up the feed tube and not into the burn tunnel and heat riser.

The whole thing will be leaking like mad. Rebuild it, seal all the seams with clay/sand and start the fire inside the tunnel. Maybe blowing gently will be necessary, this will work!

Chris Layton : For what you are trying to do, a five gal bucket with a clay slip that is thick enough to allow you to dunk your bricks and come up coated will allow you to do a test fire of your system.
This is cheap and easy,down and dirty the only limiting factor is how dirty you want to get ! If you tell people where you are, you will hear from a lot of like minded people who want to know the name of your dealer
damn you are close to your 1st Rocket ! PYRO-magicly yours , - Allen L.

I built a much leakier mock up than that and it still worked great in the driveway. You need to get the system warm to induce a draft in the proper direction. I sped up the process by using my propane torch and just left it in there for half a minute charring my kindling. Once there is warm air flowing in the right direction you should be off and running. This was cinder block which wouldnt hold up very long, already cracked a few of those square tubular blocks just messing around.

Lehi Block (in Utah)
2303 North 1200 West Lehi, UT 84043
(801) 768-8401

That's where I get the fire brick for $1.53 each for full bricks and they always have plenty. Everywhere else it's like $3 per brick.

Now are you saying that if the bricks are covered with clay slip (is that clay and sand in a thin slurry?) and stuck together to eliminate the leaks that the air will flow better?

I haven't put any bricks inside on the bottom where it is concrete. If I did that the burn tunnel would only be 4 1/2 inches high by 7 1/2 inches wide. Would that still work with that more restricted burn tunnel?

I know when I put it in the house it will have to have fire brick lining the bottom of the burn tunnel but I just want to make sure that it's not going to be too narrow.

Thanks,
Chris

Chris , You are just trying to fill in gaps, make your bricks just a little more uniform and tight fitting, you want to be able to take this apart when you are done!

Just clay and water to make a thick slurry , like a thin pancake batter this should give you a coating that sticks uniformly, small air bubbles are fine at this stage.
While you are not doing any thing to ruin a bucket save this bucket for this job, and you can wait for the clay to settle-out, pour off the water, and seal the bucket
or float some plastic wrap or Aluminum foil on top to save this for later.

I want you to fill in the bottom with bricks, your 4.5 X7.5 is a good number. I like the larger size of your feed tube you can always restrict the flow by covering part way with a brick.
you should have some perlite or other insulation under your Burn Tunnel to help every thing come up to temperature fastest - unless you really want some of your heat to go into your
underlying concrete pad ! This is a personal choice and if you are trying to limit your thermal mass bench for any reason you may want to let some heat go into your concrete slab!

Hope fully you managed to get a 55 gal drum with one end open, a plain/blank top, and clamping band! ( a second blank top would be nice) It should be burned out - the gunk/liner
from the inside and the paint off of the outside, its kind of the next step !

You do have a copy of Ianto Evans' great book, 'Rocket Mass Heaters' , don't you ! it really helps at this next step. Again you are SOooo close - PYRO_magicly yours Allen L.

I see a single notched brick ,you will probably need to do that later to build the base for your barrel to set on !