• 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 skip experiences global resources cider press projects digital market permies.com private forums all forums
this forum made possible by our volunteer staff, including ...
master stewards:
  • Anne Miller
  • Pearl Sutton
  • r ranson
  • Nicole Alderman
  • Mike Haasl
stewards:
  • paul wheaton
  • Joseph Lofthouse
  • James Freyr
master gardeners:
  • Carla Burke
  • John F Dean
  • jordan barton
gardeners:
  • Jay Angler
  • Greg Martin
  • Leigh Tate

Quick Change secondary air stub

 
gardener
Posts: 4054
Location: latitude 47 N.W. montana zone 6A
1248
cat pig rocket stoves
  • Likes 3
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hi All; Been burning my 6" & 7" batches hot, all day everyday. Both are located in large poorly insulated building's.
After 3 months the cobra head on my shop batch spalled enough, to just fall off! Leaving me with an open top 3.5" tall tube.
Needless to say performance suffered.
I removed the door and then the secondary tube. As I have a full working shop, it was little effort to cut off the remains and build and weld on a replacement. Problem fixed! But maybe not so easy for others without metal working tools and a ready source of metal.
I started looking at the stub on our studio batch. I could see that it was spalling badly and was going to fall apart soon as well.

This is an issue eventually with any batchbox. But in normal use, several years is expected. Replacement could be accomplished casually over the summer and not winter while it is snowing and well below freezing.

I decided to design and build a secondary air tube with a quickly replaceable stub... before my studio batch stub rotted off.
I succeeded by about 5 days. The studio stub did the same thing the shop stub did, there one minute and gone the next!. I was glad I had a complete replacement tube with a quick change stub already built. It was about an hours work to completely replace the secondary tube. I switched from the shorter cobra head to the taller Walker pipe. Performance appears identical (I have no Testo meter ). Now when this pipe spalls down to a shorter length, it will take seconds to drop in a 6" piece of schedule 40 2" pipe at a cost of a few dollars.

For those of you with metal fabrication ability's. schedule 40 2.5" @ 1.5" tall with a 6" schedule 40 2" stub slips right in.
For the cobra style 1.5" tubing slips into 1.75" tubing.

I am now making and selling both designs online.
Visit my shop at
https://dragontechrmh.com/
20210107_141247.jpg
Walker style
Walker style
20210108_125826.jpg
Cobra style
Cobra style
20201226_085125.jpg
What was left
What was left
 
"Don't believe every tiny ad you see on the internet. But this one is rock solid." - George Washington
Morgan Superwool Plus non-ceramic fiber blanket for Rocket Mass Heaters
https://permies.com/t/153507/Morgan-Superwool-ceramic-fiber-blanket
reply
    Bookmark Topic Watch Topic
  • New Topic