Explanations please for unique sidewinder rmh

Another glorious winter day in North Georgia: snow with high of 30 and low of 15F, with no mosquitoes or ticks in sight.  
Woodstoves are burning, all 3, in our house today
Which prompts me to understand the creation from the inimitable Peter last year. I just reread his description in "Mass bench fed directly by a modified sidewinder Shorty core" and need help before I start gathering supplies. Well, and to gather my wits for a challenge.

1, are those 8 large pieces  i see custom cast refractory slabs? I saw Thomas and Gerry build their shorty core last year,nand I understood how and why  they cast those specific pieces. When I viewed Peter's work via Sketchbook the detail of size makes me think yes. Were those hand cast first , before assembly began?  

2, this was made in record time , much of that praise is naturally to the craftsmen involved.  Respect!  Was refractory cement used in place of 1:3 clay and sand mortar, and what was the reasoning behind that decision (longevity, strength, personal preference? )

3, was cob used ONLY for the last gasp, i.e., the final exhaust pipe heading skyward?
Thanks for any answers or opinions.  I understand Peter himself is quite busy always,  in winter months especially. I might give this a try, it would be perfect for a project going in the mountains of Portugal 🇵🇹

Rico Loma wrote:1, are those 8 large pieces  i see custom cast refractory slabs? I saw Thomas and Gerry build their shorty core last year,nand I understood how and why  they cast those specific pieces. When I viewed Peter's work via Sketchbook the detail of size makes me think yes. Were those hand cast first , before assembly began?

None of the refractory slabs were cast, those are large firebrick slabs, that's all. Also, this was the material that happened to be available.
If I had the choice, I would use large concrete pavers for the bench, top and seat. The core is another thing, I suspect those refractory slabs aren't available in the US. So, you have to hand cast those.

Rico Loma wrote:2, this was made in record time , much of that praise is naturally to the craftsmen involved.  Respect!  Was refractory cement used in place of 1:3 clay and sand mortar, and what was the reasoning behind that decision (longevity, strength, personal preference? )

The whole of the thing was raised in just three short days, several guys working on the core and the bench simultaneously. The mortar used could have been clay/sand, but we used something else, a very versatile paste, not being refractory as such, very thin seams possible. Again, that happened to be available.

Rico Loma wrote:3, was cob used ONLY for the last gasp, i.e., the final exhaust pipe heading skyward?
Thanks for any answers or opinions.  I understand Peter himself is quite busy always,  in winter months especially. I might give this a try, it would be perfect for a project going in the mountains of Portugal 🇵🇹

No cob was used for the entire thing, just bricks, slabs and the mortar paste. This was specific to France, by the way.
The thing would be a very potent heater as such, able to be refilled almost indefinitely. And yes, winter is a very busy time of year, half of my days are spent in front of my computer screen.

Peter van den Berg wrote:I suspect those refractory slabs aren't available in the US.

I have purchasesd 18x18x2.5" super duty (over 40 Al2O3) slabs for around $30 a piece in Los Angeles. I do not know the manufacturer. It could be HWI. Well stocked refractory material stores should have them.

I am much obliged, and motivated to try this exact heater ,,,,,,first in the states, then assist a build in March , northern  Portugal.  The entire construction industry there is masonry-centric which is fortuitous
If I decide to try this paste in March, could you recommend a specific brand, one you have used ?  I can look at Leroy Merlin, a large network that's only 9 km from the project.  Other small masonry supply stores could have similar pastes. I will look at all possibilities there.
Again, thank you for your kind instruction Peter.