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Need help building a rocket stove  RSS feed

 
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I have a welder, an angle grinder, cutoff tool, etc and a bunch of non-galvanized water tanks.
I want to purchase a 4"x4" length of Square Tube steel (see the video here from a guy on ebay selling them https://www.youtube.com/watch?v=9ks8HQothtk#t=76)

Here is what I want to do:

I want to take one of the water tanks and cut it in half and weld it after I am done constructing it. I want to cut a hole for inserting wood and perhaps do a J-Tube.

My questions are in the lengths I should cut and the size of the tubing.

My place is 200 sqft tiny house stick frame.

I want to do a J-tube, but it doesn't matter.
In general, is using steall square tubing that is 4"x4" to big or to small? There is 5", 6", and 3". Does the size matter? Does the inserting-wood-side need to be bigger or smaller then the exhaust or insidie tube?

What should be the size of the inside tube pipe?
What length should be the tube inside the steel water tank?
What clearance should it have from the top of the water tank?
What clearance should it have, if at all, at the bottom of the tank?

What should be the length of the side insert where I place wood?
How far out should it come from the water tank?

What should be the size of the hole for the exhaust?
Should the exhaust be above or below the firewood insert area?

What should be the thickness of the insulation around the inside tube? I want to use Perlite.
Should it be 1", 2", 5"?
What should be the cubic area inside of the water tank in general for a good burn?
Can I put mass inside the water tank to hold heat?
Can I pipe the exhaust sideways outside of my building without going through my roof?

Please help me figure this out.
Thanks

 
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It would be best if you just completely forget the idea of using the metal tube for construction of the feed/burn tunnel/heat riser. Metal is doomed to fail in a properly functioning rocket. If the metal does not fail in very short order, you didn't build a rocket stove.

A 4" J-tube is quite small and difficult even for experts to build a rocket that functions well. This is due to the ratio of surface area to volume... Too much surface, not enough volume.

Buy "the book" rocket mass heaters ver. 3 by Ianto and Leslie. Youtube is full of crap, anything you see there needs to be further researched to find out the legitimacy of the info. For example, the flower pot tea light candle heater fad. As if four tiny candles are able to heat a room because they are warming a flower pot. Garbage is presented as gold and is spreading uncontrollably.
 
david james
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Can anybody else help me do this with metal? I need encouragement. This is what I want to do. please help.
 
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Location: Southern alps, on the French side of the french /italian border 5000ft high Southern alpine climate.
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david james wrote:Can anybody else help me do this with metal? I need encouragement. This is what I want to do. please help.



David, nope, anybody sensible enough wouldn't help you to risk killing yourself. Which in the end could be the result.

Metal is doomed for rockets burning core!

Watch this video.



See the state of the 310 stainless steel after a season?

Tho, there's another idea in there, in the way he makes the heat riser. You could buy splits and even make the whole burn unit this way, with firebrick splits and angle iron.

Look at this



Fourteen burns got it in this state. The metal spalling, and the elbow where the wood was burning, which is 4" 1/4 thick hydraulic pipe, was like puff pastry inside! I thought i knew better than others.



Hth.

Max.
 
Those who dance are thought mad by those who hear not the music. This tiny ad plays the bagpipes:
What makes you excited about rocket ovens?
https://permies.com/t/90100/excited-rocket-ovens
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