Mongolian hot pot table

[graham]

I'm interested in building a table for a Mongolian hot pot.  I think you can substitute any nationality that does a hot pot which is basically a cooking container in the centre of the table under constant heat.  These days it's either powered by gas, or electricity.  If each person has their own pot, then usually it's electric and sometimes charcoal.

I'd want the wood feed to be accessible.  I don't think anyone wants to crawl under the table to feed wood.  A chimney to take the smoke away would be nice but really if the rocket stove is working well, there should be no smoke.

Dragonfire.us have a table they sell with a TLUD stove for this purpose www.youtube.com/watch?v=pII6wdKyuV0

But I'm wondering what's the best configuration to use if you were to use a rocket stove.  I'd not want the feed to be at ground level, and I'd want the riser to come up in the centre of the table, preferably one that seats at least 6 people.

Perhaps a J tube with a broken riser angling up at 45 degrees to the centre of the table, but the feed outside the table?

[graham]

So, assuming a table of diameter 60 inches at 30 inches off the ground, and if I use a 8" diameter J tube, and if I want the feed tube outside the area of the table, and with a burn chamber of 24 inches, then I need a riser of 32.31 inches long at an angle of 21.8 deg off from the vertical. So, unless I bury the burn tunnel in the ground, my riser is going to end up 4 inches short.

[satamax]

permies.com/t/86886/Rocket-stove-hot-plate

[graham]

Looks like Fox excavated to get the right length for the riser. That's not an option on my deck. If I can increase the length of the riser I'll need to increase the angle from the vertical if I keep the table height at 30 inches. So if the hypotenuse or riser becomes 36 inches, then the angle off from vertical for the riser becomes 33.5 deg. I gather riser efficiency is not that much affected by being off the vertical.

[graham]

I thought I'd try and save myself some work. So I built the table and tried using a gasifying camping stove to heat up the hotpot.
And that didn't work. It wasn't able to keep the boiled water hot when we added vegetables etc. So, in the end I had to fire up the DSR2 and use the 5 mm metal plate on top of the top box.

So, it's back to building a batch box or J tube.

[graham]

I got another camping stove in the mail yesterday. It's a Nomado fire jet, a multi-fuel TLUD stove with a USB fan driven by a power bank. Cost USD80 including shipping from China. Claimed to be able to boil 3L of water in 3.5 mins! Well, it didn't do that but I was able to boil a 2 litre kettle in 11 mins, and I was able to keep boiling 4 litres of water in my hotpot. Does need regular feeding with pellets, and bits of wood.

Also claimed to reach 1000C but I only got 700C around the rim.

So, it's a gasifying camp stove with an electric fan boost.

I think it'll suit my purpose if I can find a way to keep feeding it while we're cooking without having to take the hotpot off all the time.
The website has disappeared so maybe the manufacturer is no longer extant.
Disclosures: none


youtu.be/Nt3zUlMK8ao

[DCish]

5 min riser (6" stove pipe lined with 1" ceramic fiber insulation) with a couple of cans lined with ceramic fiber tacked on the bottom to make a j tube to feed it with? Screen mesh "feed tube" to drop small fuel chunks down and guide them to fall into the burn pot so that you don't have to crawl down low to feed it? Might take a little crouching to get it started, but should run for a good while like this. I have a grill I run on top of a J (donkey32.proboards.com/thread/2301/gas-grill-rocket-conversion), but I never put any thought into a crouch-less feed before now.