• Post Reply Bookmark Topic Watch Topic
  • New Topic
permaculture forums growies critters building homesteading energy monies kitchen purity ungarbage community wilderness fiber arts art permaculture artisans regional education experiences global resources the cider press projects digital market permies.com private forums all forums
this forum made possible by our volunteer staff, including ...
master stewards:
  • Nicole Alderman
  • r ranson
  • Anne Miller
  • paul wheaton
stewards:
  • Jocelyn Campbell
  • Mike Jay Haasl
  • Burra Maluca
garden masters:
  • James Freyr
  • Joylynn Hardesty
  • Steve Thorn
  • Greg Martin
gardeners:
  • Carla Burke
  • Dave Burton
  • Pearl Sutton

5 Gallon Pocket Rocket, is 4" chimney and intake too small?

 
Posts: 3
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
My son and I had a great time today building a simple pocket rocket using materials we had on hand, including a 5 gallon bucket, a 4" chimney pipe and a 4" piece of square tube for the intake, but we had overall poor results and I'm not sure if it is due to the pipe sizing or the location of the intake from the bucket bottom (about 1.75").

At start up, she seemed to be doing fine: built up some good heat, was drafting fine the right direction and whatnaught, but did not build the amount of heat I've been seeing on Youtube, if you know what I mean. And she didn't ever get that signature 'rocket' sound. Then she started smoking out of the intake, intermittently, but eventually consistently. Finally I shut her down, disassembled and found that there was enough un-burned material (including plenty of paper from starting the fire!) built up to block the intake's distance to the bucket bottom.

Is 1.75" not enough clearance for a 4" pipe? Or am I missing something?

Pics attached.
IMG_0703.JPG
[Thumbnail for IMG_0703.JPG]
Assembled rocket, smoking on both sides...
IMG_0704.JPG
[Thumbnail for IMG_0704.JPG]
Disassembled lid, and apparently my finger...
 
Perry Pillard
Posts: 3
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
So after my previous post, I became convinced it was the gap between the bottom of the intake and the bucket bottom, ergo, I lopped off another half inch of the intake. Tested again and found almost identical results of the first test run. Very distressing. To increase chimney resistance and force the path of least resistance for oxygen to be the intake, I added another chimney section and more than doubled my chimney length vertically. This had immediate results and served to be the turning point of the stove's performance. Within minutes, we saw red glows emanating from the base of the bucket, and you could hear the telltale rocket rumble. It was pretty cool, err... hot.

Stage one complete: baseline testing is a success. Stage two: integrate this little heater into my shop.
 
Perry Pillard
Posts: 3
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Here's another question: Has anyone integrated a waste oil drip to increase wood efficiency?
 
Can't .... do .... plaid .... So I did this tiny ad instead:
Switching from electric heat to a rocket mass heater reduces your carbon footprint as much as parking 7 cars
http://woodheat.net
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
Boost this thread!