Lancer's Philippine Build, Close to Australia Anyhoo...

[Lancer]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

mrchipster, a very good thought. :b: I can't wait until its time to do the cap!

UtahBeehiver, thanks, and yes Gary will be a winner in all this. If he knew he would be much more excited about the project!

brickie, that's a great idea, and much better than my flue plan. I could, using bricks, build a 'brickie flue' on the actual brick dome which follows its contour until its on top of the dome then build straight up from there and out the top of the onion. Now that's !

The brick of the dome will get heat from both sides as the brick of the oven will face the fire on one side and the brickie flue on the other. I assume that some of the heat from the flue will radiate back into the oven itself.

I have some flues ordered, I'll put plants in them!

Once again brickie, an elegant solution. Thanks!

[brickie in oz]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Do you actually need a flue at all, the smoke leaves the oven via the hole where a conventional flue would go then rises inside the outer enclosure up and out of a cowl on top of the onion.
You could have a small 300mm high x 450mm x 450mm (internal) flue built of brick to exit the oven and leave it at that.

The heat rising would tend to make the smoke want to exit the cowl, I would have thought so anyway

[UtahBeehiver]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Lance,

Very interesting, and yes that is one BIG oven, nice work. Gary is going to enjoy all the scraps from the PIG.

[mrchipster]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Yes that's it mrchipster. With the folding brake and cutter I could build a cap of sorts but the actual design, well I've searched on Amazon and found some I could copy, but I'm not happy with having a big silver thing on top of the dome. Thought about copper. Still thinking that one over...

Might have the potter fire a cap..., not sure. If it was a fired cap I could tile it but its going to turn black anyway, so black tiles? No solution is a good solution.

The top won't actually be 3 sided as I'll work it round as it comes out. (Actually just the way you drew it. )

No worries about the blanket, I'm sure 12" of pumice will get the job done. Living on the Oregon Coast is not much different than living on Bohol, a million miles to anything. If Amazon sells it I can get it through Oregon to here, if they don't, well I'm outa luck. Pumice worked for the Romans, yes?

The cap will tend to stay clean as the smoke in this case would be going out around the sides, there will be some black buildup on the edge but if you provide an ample opening you may not notice much buildup on the dome or the outside of the cap.

Take a look at my flue. The pipe is clean and so is the top of the cap. You cannot see the top of the cap but believe me it is shiny. But I would need to climb on top of the garage to get a photo and that is just not happening this morning.

I might be careful about a pottery cap, if it rains and it is hot it might crack. You might want to. Consider a cap of the style I have and have a pottery cap over it as a facade that way the pottery would stay cool and the metal would deflect the heat and smoke better, the metal cap would fit inside the facade and be almost invisible if positioned carefully.

I am sure the pumice will work great.

[Lancer]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Yes that's it mrchipster. With the folding brake and cutter I could build a cap of sorts but the actual design, well I've searched on Amazon and found some I could copy, but I'm not happy with having a big silver thing on top of the dome. Thought about copper. Still thinking that one over...

Might have the potter fire a cap..., not sure. If it was a fired cap I could tile it but its going to turn black anyway, so black tiles? No solution is a good solution.

The top won't actually be 3 sided as I'll work it round as it comes out. (Actually just the way you drew it. )

No worries about the blanket, I'm sure 12" of pumice will get the job done. Living on the Oregon Coast is not much different than living on Bohol, a million miles to anything. If Amazon sells it I can get it through Oregon to here, if they don't, well I'm outa luck. Pumice worked for the Romans, yes?

[mrchipster]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

It sounds like you will not have a true point at the top but a point as a rain hat over a three sided vent near the top?

Maybe something like this drawing?

But I still think it may be easier to get one 9 or 10 inch flue to do the same thing as your 3 - 6 inch flues.

What about shipping the blanket with your shear and brake from the states.

[Lancer]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

I can put (3) 6" flues side by side in a more narrow area across the top of the door. Also the flues have to run >>inside<< the outer dome within the space occupied by the pumice. Easier to hide than a larger diameter flue, and it takes away less thickness of pumice.

Remember there will be no evidence of the flue from outside the onion dome. Typically a flue will rise above an arch sitting in front of the dome and determining the door of the oven. Not this one. The arch will be inside the 12" of insulation which will be within the onion dome forming 5" outer wall, also at the top of the door arch. Only the 12" thickness of the insulation makes this possible as the flues will be buried within the insulation. The actual door medieval pointed obtuse arches will stick out from the dome in an effort to do what brickie said, keep the water out. However you won't see the flues until they come out of the top, the actual pinnacle of the onion dome. With (3) I can work them around and perhaps cap them as they come out of the top with a large circle of fire brick standing sideways, not flat. Haven't thought much about that.

Anyway here's the thought. As the (3) 6" flue pipes approach the top of the onion dome the depth of the pumice will increase, the brick dome being a half a sphere and the onion dome being higher on top than it is wide. In other words the 12" of wall pumice will increase to somewhere between 18" to 2' close to the top. (Where the heat wants out anyway) So, I could carry the center flue to the far side of the other two, away from the door and bring the outside flues together, making a triangle of the (3) flues that rise towards the top. (within the pumice) On top, well that could be a round stack of fire bricks with an 12" interior dimension. Just an early thought, have to mull it over, see what you guys think.

Looked on Amazon months ago, can't find a blanket. They have rock wool but that's thick and expensive to ship. How thick is an insulating blanket? Which of you guys can go to the store and buy one big enough to cover this oven? Anyone in Australia willing? I send a check off next trip to Tagbilaran... Anyone have an Philippine LBC shipper in their town? Cost is usually less.

A lot to ask, but no worries, can manage with pumice.

[oasiscdm]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Lancer

Wouldn't it be easier if you are getting a potter to fabricate the flue to get one to size made instead of 3 flues side by side one would have to be much simpler than 3 and all the complexity that involves.

just seems to me to be overly complex solution.

Couldn't you import the blanket.

[mrchipster]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Thanks guys! I'll do (3) 6" chimneys, that enough? Three wide should fit no problem, and I ordered extra chimney from the potter.

That should do, I am very interested to see what you have planned for the flue arch with three holes in it. You may want to get some input from Brickie or other people more familiar with setting up something like that.

[Lancer]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Thanks guys! I'll do (3) 6" chimneys, that enough? Three wide should fit no problem, and I ordered extra chimney from the potter.

[mrchipster]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Gudday
2 x 6 in chimneys is that enough? The formula that I have seen recommends 15 per cent of the opening size. You got your width and oven height so door opening should be setted as well which will give you a chance to check chimney size required
Regards dave

2- 6 inch chimneys gives you roughly 56.5 sq inches of flue

2- 8 inch would provide a much better flue at 100.5 sq inches

I have a 42 inch oven with a 10 inch flue this gives me a 78 inch cross section and it breathes well, no smoke out the front. I know I am oversized slightly for my oven but I agree with Dave, you should up the flues to at least 2 - 7 inch at 78 sq inches or 2 - 8's at 100.5

Keeping with your 2 flue design.
Just my two cents

[cobblerdave]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Gudday
2 x 6 in chimneys is that enough? The formula that I have seen recommends 15 per cent of the opening size. You got your width and oven height so door opening should be setted as well which will give you a chance to check chimney size required
Regards dave

[Lancer]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Well we haven't gotten that far yet. I can tell you Dave there's pigs and there's PIGS and we'll be doing a PIG in there. Also, yes 54" is a big oven but not SO big. I took a look and there's a guy building a 48" oven. Likely that guy has access to a good insulating blanket and doesn't have to add 12" of pumice. I'd love to have an insulating blanket and fill in the pumice over it, but hard to find.

To establish the height I have to determine the sides using a piece of plywood with a half circle on it. The plywood will contact the 14" wall at a specific height and be movable as the onion rises. As it rises the wall pumice will be added in between the brick dome and the 5" concrete onion. It will have attached a level for vertical and a mark which must correspond to a mark on the 14" base. So, between the mark and the level the plywood will be established in space in relation to the base of the dome.

Onion domes are squashed spheres, not true spheres. So the half circles will not be half a sphere off the base, though half a smaller onion dome squashed sphere. This will help keep the height of the wfo down. The top will be joined by a sort of incline which culminates in the (2) 6" chimneys. The chimneys will rise from above the door to the top of the onion inside the 12" insulation. The access to the oven will be through a series of medieval pointed obtuse arches increasing in size in steps as an accent. Smaller size close to the oven larger toward the outside. I'll personally do the math on that and cut plywood forms for Sho to follow. There will also be smaller mpoas in a design around the 14" base when the time comes for pretty stuff. That should tie together the opening and the accents, theoretically.

mpoas as an accent...though in a different configuration then I have planned.

[cobblerdave]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Gudday lancer
I have just looked at those photos... More than once I might add . That oven of yours is truly humungus you'll definitly get a full pig or I recon 2 in there.
Question: how tall will the top of the structure be from the deck? Being onion shaped and all.
Regards dave

[Lancer]

Re: Lancer's Philippine Build, Close to Australia Anyhoo...

Haven't received either the bending brake or cutter yet. I order the stuff from Amazon, it gets shipped to my place in Oregon where my father in law puts it in LBC boxes and ships it to us here. So it takes 3 months, often more, to get the stuff.

Search Amazon for these and you can see them...

3mm THROATLESS ROTARY SHEAR PLATE CUTTER Cutting Sheet Metal *FREE SHIPPING* $189

30" Steel Bending Brake Sheet Metal Bender Tool $42.40