36" Pompeii Dome - Thailand

[danhem]

I don't have the paper that came with the anchor plate which had the exact dimensions, but you can also see them here:

https://www.northlineexpress.com/6-s...t-ap-5340.html

Anyway, if someone's welding an anchor plate, then I guess it doesn't have to exactly follow these dimensions - whatever way you or the welder can design a link between the anchor plate and the pipe.

You have been a great help with the links and suggestions. I've explored a couple of options - 1) Custom fit with a local metal works company 2) Contacted the Pizza Oven company website.

Both options are positive and I've have quotes from both sources. Total cost for doubled walled SS 1.5 meter insulated chimney with plate and hat is around $300. The local metals works would weld the bits together, which would be the better option, however I'll probably go with the Pizza Oven company as they are more likely to understand my exact requirements.

Hope to take delivery of the chimney some time next week.

[Yokosuka dweller]

I don't have the paper that came with the anchor plate which had the exact dimensions, but you can also see them here:

https://www.northlineexpress.com/6-s...t-ap-5340.html

Anyway, if someone's welding an anchor plate, then I guess it doesn't have to exactly follow these dimensions - whatever way you or the welder can design a link between the anchor plate and the pipe.

[danhem]

...but much less trouble than having to make a chimney from the ground on up. Although that option could be interesting/fun to try to do.

I think I’ll probably attempt this with a local supplier. My wife seems to think the guy who did our guttering will be able to help with this.

ill work to the dimensions you sent and I think it should be achievable.

out of interest do you know the dimensions of your anchor plate?

thanks again.

[Yokosuka dweller]

Ok, I am attaching a couple of photos here with some dimensions.

Sure the easiest way will be to get a selkirk or duravent sent over, even if you know someone in the states or the UK that can send it. Not cheap but much less trouble than having to make a chimney from the ground on up. Although that option could be interesting/fun to try to do.

If I were to do that, I'd probably do the anchor plate with the chimney in one piece. So then you'd have a square stainless plate in the right dimensions with four screw/bolt holes, and one 6 inch dia hole in dead center for the smoke to pass through, that would be plasma cut probably. Then the inner flue liner/pipe would be tig welded to the edge of that hole. Should be no more than 0.5mm sheet metal pipe, definitely should be 304SS, I think even 430SS would degrade too fast. Then outer shell pipe also 304, when you look at the photos, would be about 2,5 cm wider on each side, i.e. around 8"/20cm dia...then weld that to the anchor plate as well. Make sure it's dead straight, and then fill perlite or other high temp insulation in the hollow between the pipes. Then weld it shut up top. And, adding to that make a simple 'Chinamans' hat top welded to it. Probably more trouble than it's worth, but an option if it is impossible to get a chimney pipe sent to Thailand.

Yes, Japan is not easy country for retiring, even we pay into the retirement/social insurance for years, the prospects of getting much out of that are not good because there is a huge elderly population here now that of course is entitled to pension payments. It's almost like a pyramid scheme, and I have not found a good solution to when I retire although I am hoping some long-term investments will help. I'm originally from Denmark and am playing with the idea to return to that part of the world some day, not easy though these days. But Japan is beautiful and most things work well here. I find Thailand more laid back, gregarious people, great food and you get much farther with your budget there than in Japan, especially if you can stay away from the rat race and pollution of the big city.

[danhem]

.......including welding your own, casting one (which would be easier and which DavidS has advised on also in several threads), or even doing a brick flue. But that would be very heavy and require additional buttressing.

Thanks for the options, it seemed that purchasing the plate and chimney were probably my easiest option but will now explore the others.

Otherwise, since labour is not expensive, I can imagine it would be possible to get one welded from the ground on up, if you got the right measurements, and you have someone who does good TIG welding. Let me know if you decide on that and I can share some dimensions.

The dimensions would be great if you have them handy. I'll take the advice of UtahBeehiver and go with a 6". I had mapped out 50sq inches to accommodate an 8" chimney - from my reading I think the larger vent opening will be fine, so I should be good to go with the 50sq inches as planned.

The dimensions will help with my decision process for sure. Labour is indeed cheap here however the language barrier is always a problem and as you know the Thai way of doing things is the ONLY way of doing things. So even if my wife explains with the aid of diagrams and dimensions, the welder will always know best But definitely an avenue to explore.

Thanks again for your input and suggestions, I made progress with the ceramic rope yesterday and the service a TrueSeal seems quite approachable for standards over here.

As an aside - my neighbour who has helped with parts of this build worked for Nissan in Japan. He tried his hardest to retire out there as he loved the place so much but had a many number of hoops to jump through proving almost impossible. Your a lucky guy to be living out there, just something about Japan that is highly appealing.

[Yokosuka dweller]

Hi Danhem,

Man you're progressing fast. I guess that's one of the good things about the covid situation, that we can spend a lot of time on different 'home improvements' such as especially a WFO!
I'm not sure March 2021 will be back to normal, but when...that's anyone's guess.

On chimney, I looked around a LOT here in Japan. And they do have local manufacturers of single and double walled chimneys, but none have the traditional anchor plate probaby beacuse masonry work is uncommon due to the earthquake prone region this is. There are work arounds for that, including welding your own, casting one (which would be easier and which DavidS has advised on also in several threads), or even doing a brick flue. But that would be very heavy and require additional buttressing. I didn't have that space, so eventually bought one over amazon from the US. I chose a Selkirk because they had 6" size, and the anchor plate was relative easy to get but not cheap. I got a 24" flue and it draws well enough even though it is far from the recommended height of 4 feet. So now, because I am planing to build a shed style play room around the oven, I bought another flue piece also on amazon to enable a higher roof structure. That might take a long time to arrive, but eventually it will I hope.

For Thailand, I imagine it will be difficult to source and customs there sometimes take international packets hostage for large payouts. But i found this website: https://pizzaoventhailand.com/ In English. try to give them a call and see if they can source a chimney or even if they have some handy. Otherwise, since labour is not expensive, I can imagine it would be possible to get one welded from the ground on up, if you got the right measurements, and you have someone who does good TIG welding. Let me know if you decide on that and I can share some dimensions. You also have to decide on single or double walled. Latter is more expensive but is said to draw better, doesn't heat up the surrounding bricks at the foot of the chimney and therefore doesn't risk cracking that part of the oven. Single wall is a lot cheaper and could be any kind if stainless pipe of the right dia.

[UtahBeehiver]

6" is adequate for a 36" oven and with 8" you will have to flare out the opening to get the adapter plate to fit. Even the 6" the vent opening will require a little adjustment.

[danhem]

Ive been saying it for a week or so now but I am finally ready to move on with the vent and chimney. I think Im clear on what to do and see the process to be much simpler than the inner arch. Since my inner arch bricks extend fairly deeply away from the oven i will use the outside of the inner arch as part of the vent opening and build the outer arch accordingly.

I have around 1/2 brick from the back of the inner arch brick and will lay another full brick to make a vent depth of 13.5" from the oven opening point (center line of oven to 18" radius point). The outer arch will follow the inner arch design - 3 bricks up flush to the inner arch back side bricks before the arc begins. To accommodate the vent opening i have mapped out an area of 50 sq inches. At this point in the arc I will use 1/2 bricks for the outer arch to leave a gap between the back of the inner arch bricks and the outer arch bricks (taken this idea from Utahbeehiver's design). Once in place the transition for the flue will hopefully sit firmly on top of the arches.

Looking at anchor plates and pipe options. I guess the FB store is as good a place as any to start. With that in mind - for a 36" oven, is an 8" pipe the best option for better flow over a 6" pipe?

Thank,

Danny.

[danhem]

So finally closed the dome in today. My 7 year old boy was on hand to smash the key stone home. The stone itself was one of the easier cuts Ive had to make over the past couple of days. Courses 9,10 and 11 put my new found (still finding) masonry skills to the test, mindful that the tighter things fit together the better, I made a special effort on cutting the last brick on each course with as tight a fit a possible, even to the point where I had to hammer the brick home for a tight fit. Seemed to work out fine if not entirely by the textbook.

The keystone is a single 4.5" brick, cut into a skewed six-sided shape. It would be unfair to call it hexagon in its truest form but it basically has 6 sides and, most importantly fits in its hole very snug.

All in all thus far Im happy with the build. My DIY skills are next to none and with the Covid store closures and simple lack of adequate brick cutting machinery here in Thailand, Ive managed to overcome the inner arch conundrum and have a dome that is a near perfect 18" radius.

[danhem]

Many thanks Yokosuka, I will get on to True Seal Corp today. Seems like the expansion benefits of the heat break could help to save my oven from failing mortar..

I’m nervous as hell about the mortar failing during the curing process. So much so that I’ve already prepared myself to break the oven down brick by brick and to source the ingredients for the home brew. Seems that SvH has been through 2 builds in Thailand already and is preparing a third with locally sourced home brew materials.

Should I have to break it down, at least I could correct a few mistakes and the rebuild should be fairly easy assuming I can recover all/most of the cut bricks (cutting has been unbelievably time consuming).

I see you build is coming along nicely, great picture of the oven with fire and all it’s glory. I’m longing for the same same day.

Out of interest, where did you order the chimney from, I’m guessing it came from overseas, even from FB itself?

PS. - you may remember that I had a trip planned to Japan in March this year. Cancelled unfortunately due to Covid. I managed to recover our flights and accommodation in the form of credit so watching the situation over there carefully ready to book the trip again for March 2021....hopefully. I see Hokkaido is facing some sort of second wave crisis.

[Yokosuka dweller]

Rockwool wouldn't work I think - not rated for high enough temps I'd say. I didn't use ceramic board so not sure about its consistency, but i guess it would work for a floor heat break if you cover it with something that is abrasion resistant. Anyways for my floor heat break I merely used a square stainless tube and filled the area below it with perlite/cement mix and left air inside the tube. For the arch heat break I used ceramic fiberglass rope. It's stuff you don't want in your food which is why the L-shape cut allows you to place it on the top of the inner arch. I googled a bit and found two websites in thai that describe heat resistant gasket rope. One has asbestos, which I didn't think people used anymore. But given 'this is Thailand', some differences still exist. If no other option, then that would be an option.

https://www.ntiheatprotection.com/ro...-for-750c.html

https://www.nanasupplier.com/kimtech/p-187102

Edit: here is another supplier that has higher temp rates ropes: https://truesealcorp.com/products/insulating-textile/

But for these you might have to call and talk to them, I could imagine that with the current lack of global imports situation they may not have it.

[danhem]

I copied Utah's floor heatbreak and JR's (and others') L-shape brick heatbreak around the dome opening arch. I can say that when firing, there is a 20-30% temp difference between the heat breaks. Of course the distance from the fire itself must make a difference too, but I think heatbreaks have some significance. But as DavidS has said many times, it is more an expansion break than purely a heat break so that's also an advantage to reduce risk of cracking arch through these heatbreaks (although my arch developed hairline cracks eventually anyway). All this being said a well insulated door will break more heat than either of those heat breaks.

Okay thanks. Still trying to weigh up whether to add the heat break or not.

Main factor being what material to use. I see most have used some kind of ceramic rope. The supplier here in Bangkok doesn’t stock such a thing. They do supply RockWool - not sure what it is or whether it will serve the purpose of a heat break?

I did wonder whether the left over ceramic fiber board would be ok to use also.

[Yokosuka dweller]

I copied Utah's floor heatbreak and JR's (and others') L-shape brick heatbreak around the dome opening arch. I can say that when firing, there is a 20-30% temp difference between the heat breaks. Of course the distance from the fire itself must make a difference too, but I think heatbreaks have some significance. But as DavidS has said many times, it is more an expansion break than purely a heat break so that's also an advantage to reduce risk of cracking arch through these heatbreaks (although my arch developed hairline cracks eventually anyway). All this being said a well insulated door will break more heat than either of those heat breaks.

[UtahBeehiver]

I did them, both floor and dome to arch. Are they worth the effort as far a effectiveness, can't say for sure since I do not have a baseline to work from. That said, floor and dome and a good insulated door are based on members experiences to be the most effective heat retention measures. Gulf did a nice "L" shaped vent design for his insulated archway. So kinda up to you, necessary, no but nice non the less.

[danhem]

The opening in the top of the vent chamber should have at least the same area as the ID of the chimney, 8" ID chimney equals 3..14 x 4 x 4 or 50.14 sq inches so the opening in the vent arch should be at least this amount with a smooth transition from rectangular shape to square or round..

OK thanks, I think I've managed to work it out from your explanation and from looking at the pics in your build. Many thanks.

Also I see many builds use a heat break. Is this an essential part of the build?