Rocket J tube layout

I am finally going to build a simple firebrick J-tube to heat something outside.  I'm a bit surprised that I can't find simple dimensions or firebrick layouts for a 6" or so sized system.

I can get full or split bricks but I'd love to buy about the correct number.  Is there a "no cut" layout for a J tube that I could just work from?  Thanks!

This is the only video I could find.  Seems like he could flop the top of the burn tube bricks on their side to save 2 bricks and go from 2 to 1 at the far side of the base of the riser.  So maybe 58 bricks...  

It also seems this layout gives a 6.5x6.5 wood feed and riser and a 7 x 6.5 burn tunnel which seems good enough for me...

Hi Mike,

Several sources to find basic J tube layouts:

The Annex plans by the Wisner.- Often see it as a freebie offered on permies

The Rocket Mass Heater Builders Guide.

Ianto Evans & Leslie Jacksons book
https://www.rocketstoves.com/case-studies/kirk-mobert/

Lots of sketchup files posted on permies and proboards
One I found:
https://permies.com/t/91714/Sketchup-Rocket-Core-Designs

Good luck Mike and have fun!

Thanks Gerry, I'm surprised there aren't some that are a bit easier to see.  Youtube, website, permies, etc

Mike, you have to bare in mind that rocket stoves are not exactly an everyday occurrence in most peoples lives!
The metal, camp site rocket stoves are quite well covered but a heavy brick rocket stove are simply  not a common place fixture in peoples homes.
To the best of my knowledge I am the only person in my catchment area of 65k people who actually uses one, I doubt if there are more than a handful across the whole of the UK and northern France!
Obviously in ‘off grid’ places they are more popular and some of the more compact designs are uses in a few European homes but you also have to bare in mind that in many places in the world there are strict building codes that only allow  tried and tested wood burning stoves.
That leads us on to  the new  generation wood burners that you can just walk into a shop and buy.
They are insulated, use secondary air, dont smoke  and look really neat and smart.

So that is probably why there are not many video on youtube.
I think will the development of ‘the bell system’ rocket stoves like Peters latest designs, at least have a chance of becoming more popular in the future but I also believe that heavy brick rocket stove will only ever be of a tiny minority interest.

Found this one Mike. First 3 minutes shows a possible brick layout for a standard J tube

J tube layout

Thanks Gerry!

Re "flopping the bricks on their side" to save two firebricks: First, the dimensions would alter slightly as firebricks are not exactly modular in thickness compared to height and width. (2 1/4" thick would make them fit perfectly in any orientation.) Second, having the bricks on edge in the burn tunnel roof makes them stronger in that high-heat, high thermal shock location. The leading brick in the ceiling of the burn tunnel is known as the first one to crack.

Thanks Glenn, that makes a lot of sense!