20# tanks stove

[keithturtle]

I've been working for a while on an airtight woodburning stove made from a pair of 20 lb propane cyclinders. The gist is, recycle expired tanks into a usable woodburner.  The bigger picture is, SHTF, nobody can get fuel anymore, so why not reuse something otherwise considered useless?

Still working on the final iteration, but so far I've come up with a burner plate perched atop the flue stack, which is castable refractory to handle the heat and provide support. Skin temp at top in front of stack approaches 800*F.

If there's any interest, I'll take some pics and post the progress.  I've learned a lot along the way; and while this isn't anything approaching ZPE, it is a pragmatic approach to a practical means of providing heat in troubled times (as long as wood is available). Also planning on a pellet basket, but I'm pretty sure it will require more elaborate air supply to maximize the pellets

More later

Turtle

[zero]

Funny, I would think at least 3 of those tanks would be needed to approach what I'd think is the minimum height for a tall enough riser stack inside.

[keithturtle]

Yeah, think small wood stove, not rocket.  The firebrick cast flue serves as the cooking base; attach metal flue pipe to that for inside use. I came across this vid that looks alot like mine, with several changes

https://www.youtube.com/watch?v=7oIJpD2dPX4&feature=iv&src_vid=qRcGkcGaVlY&annotation_id=annotation_2837974753

Pics soon

Turtle

[keithturtle]

Pics soon

As usual, life gets in the way.  Still working on this as I can.  A plasma torch has really sped up the process

Turtle

[keithturtle]

This thing burns pellets; looks promising

https://www.youtube.com/watch?v=y7xvx8khoiM

Turtle

[zero]

Not sure how you adapt that to a rocket but watching with interest!

[keithturtle]

Not sure how you adapt that to a rocket but watching with interest!

An experienced rocketeer gave me the inspiration for a two-piece cast core that will indeed fit inside a 20# tank

http://donkey32.proboards.com/thread/2180/another-attempt-apply-rocket-technology

I'm still working out the details, but making progress slowly

Turtle

[Ozone]

Think Zero has lost the plot

[zero]

That's very impressive work. Last post to that thread wan May. Wonder what's happened since?

[keithturtle]

Nothing with that design.  He put up a site sharing all his work.  He does not believe "brain drain" is a good thing

http://batchrocket.eu/en/designs#brick2

Turtle

[keithturtle]

I've covered a fair bit of ground since the last post.  I found a way to make a rocket heater from the 20# cylinder.   The radiant heat is great, but directed heat is proving to be a challenge.  More when I find the pics, of get the next version done

Turtle

[zero]

From only one 20# cylinder? Or stacked?

[keithturtle]

(Z, I never even considered a stacking arrangement for the rocket tank.  Now you've got me to thinking...)

I thought being retired from full time work would make for real progress on this project, but it just ain't so.  Still, this rocket burner from a single 20# tank is coming along.   Since there is so much heat generated at the point where sticks burn, I radiused a couple thin firebricks and cemented them into the base of the tank.

I used a "sort of" refractory blend of  1 portland cemment, 1/2 fireclay, 2 fine perlite, 2 mason sand.  This holds up really well in the two-tank vertical woodstove. 

The first rocket tank design had a tremendous burnback, with the sticks burning up the feed chute.  I think I can address this by sleeving it with an air transfer parseage... quite simply, a 3" square pipe inside a 4" square pipe.  Still gotta arseemble and test,  but this oughta work real well feeding pellets, once I get the flame grating figured out.

Dear God, this stuff takes so much time, but I'll get there eventually

Turtle