My 6" batchbox sits on top of what was my 8" J tube.
I have a brick and cob horizontal transition area with an ash pit and a cleanout port all covered by a large thick rock.
My 8" pipe runs 12' thru the mass, makes a 180 turn and comes back 10' before turning vertical.
As an 8" J tube I had a bit of trouble with the initial draft at the start of the season and in the spring when it was warm outside.
A handheld fan blowing down the feed tube reversed it easily and a few minutes later the draft took over and all was good.
With the 6" batchbox. I have triple the mass that I used to have. All that mass must heat before any heat is left to warm the piped mass and start the draw.
The primary intake on a batchbox is less than half the size of an 8" feed tube. Blowing a fan helps, but it is not working to my satisfaction.
This means I need a bypass. I installed one on my 7" batch in the shop and it works great!
Now we need one in the studio!
After looking over what I had to work with. I decided that drilling straight down into my transition area was the best place to pickup hot air.
Surprisingly... https://dragontechrmh.com/ donated a 4" bypass gate for the project!
A 4" diamond core drill was used to bore a hole thru the clay bricks. A trench was then excavated over to the vertical chimney.
With a few modification's and some Morgan super wool to seal things up, the gate slips nicely into place.
Today I received a 4" black 90 degree turn. Sadly the 4" straight pipe did not arrive today.
After carefully measuring the location. Using my 4" core drill, I went down thru 3" of solid rock.
Then I had to elongate that hole to allow the pipe to start over the gate.
Once in place I drilled a 1/4" hole and bolted it to secure the pipe to the bypass gate.
A few wraps of metal duct tape to help seal things up and finally some twisted steel wire to make sure its sealed.
Some Morgan super wool to seal the pipe as it enters the transition area . (Morgan super wool is the Duct tape of RMH's)
And finally a coating of cob to pretty it all up.
As soon as the straight pipe arrives (it was in Billings this morning) I will drill into the vertical pipe and make the final connection!
I can hardly wait!
Photo's of the finished job will follow at that time.
Its never too late to install a bypass. Such a wonderful tweak to add to any build that not only has startup issues but also to a stove you want to start in the summer (as an indoor cooking unit for example) so that you don't overly heat up the house with stored heat.
Takes the reliability issue up a big notch with making sure everything works as its supposed to.
Thanks for the documentation Thomas.
Bypass install 100% complete!
Small amount of smoke leakage at the gate that quickly went away.
Gas temperature inside the exhaust stack was rising within 5 minutes!
Previously it was at least 30 minutes or more before the dragon breath monitor started showing any heating at all!
This will allow Batch use all year during any outside temp conditions.