A happy...accident.

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A happy...accident.

Postby smallhagrid » Tue Mar 25, 2014 7:02 pm

Hi Folks.
I am still using the RH that I built & posted the details of here - and it's working very well for me.

As you may recall from what I posted, it sits up off the floor and because of how it is built there is zero heat getting through it's base so I literally store kindling under it.
It also has lots of zigs & zags in it's exhaust which really help in keeping the outlet temp low and the heat indoors.

It's burn tube is only 6" and the firewood I've used ranges from stuff I picked off the ground in the woods - to old, dry kindling - to seriously nasty hardwood that was supposed to be dry - but was not.
And it burns it all just fine with the exception of wood that is so wet as to be almost fireproof (that just takes longer to start...!).

The rocket tube WAS connected by an elbow that I used as a mold for masonry - which has all been burned away now,
In addition - I'm pretty sure that all the perlite insulation has fallen out & been removed with the ashes.

Sillier still, here's the happy accident IMO=>
I'm about 99% certain that the rocket tube itself has seriously melted to where it is no longer really any sort of tube anymore.
This has changed how the RH burns, but not in any bad sort of ways.

As a result - what I'm thinking about the RH subject now is mostly about bends & vortices.

I think the straight rocket tube is a fine place to start - but not even close to being the whole answer for good burning & low outlet temp. when using wood as the fuel.

Seems like the fire in mine has opened lots of holes in the rocket tube and what goes out now must be doing a lot of swirling.

The barrel has lots of isolated/new hot areas that it did not have before - and the outlet temp is still nice & low.

If I ever make another one (or fix this one) I'm thinking the upright tube will be shorter and have obstructions placed into it on purpose, maybe several openings, a 90 degree final opening at it's top, and be 100% made of bricks & mortar.

For my liking the burn tube needs to be bigger too - LOTS bigger than the 6" one I've got - and in mine I'm quite certain that the outlet need not be any bigger - so it'd be more like a masonry box stove that feeds into a short rocket tube (of sorts) into a barrel, etc...with a forced draft outlet that is made for that purpose.

All that, with all the bends I put into the long outlet tubing really seems like it would work well to me.

One last thing:
The forced draft I made for it;
This is definitely one of the better things I've ever come up with totally by accident & it's staying in any RH that I will make as it works incredibly well since I improved it's design.

I cannot take the RH apart to study it's innards just yet - so that's all for now.
(Sorry I cannot have any photos to better show what I've been observing of this in daily usage...)

Best Wishes to All !!!
Posts: 72
Joined: Fri Oct 18, 2013 2:08 am
Location: Vermont

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