Tims oven - early days! Brick Oven Photos Discuss Tims oven - early days! in the Good Background Information forums; Hi Salv, The vent opening was designed so that I had at least twice the area of the actual flue ...

[Tim F]

Hi Salv,

The vent opening was designed so that I had at least twice the area of the actual flue pipe. I just made the entry 300mm deep, and after a few courses of this arch I stopped and continued on as 2 separate arches, 60 and 75mm wide at the back and front respectively. That gave me an opening 165mm deep, so then I checked how wide it would need it to be to give me the area I wanted and started the 2 arches at that point. I will do a sketch if I haven't explained that well, but I think you can see it in an earlier photo.

I made the vent to sit about 10mm outside of the opening. It was cut out of 0.9mm stainless, and I used a thin cutting disk on an angle grinder. Neil folded and mig welded the pieces together for me (and suggested a much better way I could have designed it, out of 1 piece rather than separate side pieces). To attach the pipe, we used a short length of pipe, cut flaps in the bottom and bent them out, then pushed that through the hole in the top of the vent and welded it on. The dimensions ended up being 190mm deep, 450mm tall, 190mm wide at the top of the front and back faces, and 420 wide at the bottom of the front and back faces. After cutting the base to fit snugly around my entry arch, I used 4 small dynabolts to attach it and then ran some mortar around the inside where it met the brick to ensure a good seal.

I think if I did it again I would probably go the 8" flue but I did find that if I held a piece of ply against the top part of the front of the entry arch, all of the smoke that was escaping was blocked and sucked back up the chimney. So actually this could have been solved by a slightly better arch design.

[Tim F]

Actually could a mod please change my thread title suffix to something more appropriate like "making pizza"? Didn't realise you couldn't change titles when I started it.

Todays project is to figure out at least a makeshift door so I can do some bread.

[Tim F]

After the third firing there doesn't seem to be any increase in in the cracks around the insulation. Holding my hand over the cracks, they don't seem to let out any more heat than the uncracked parts either, which is a relief. Now that it's all dry properly the insulation seems a lot more effective too - last night I lit the oven at 6.30, and at 10 I could hold my hand against the dome comfortably. I will post some graphs as soon as I get a decent thermometer to measure the inside and outside properly.

[Salv B]

Hi Tim,

Thanks for the info on vent opening dimesions etc.. It was very clearly explained and helped considerably with my thinking on a solution for my oven. I should get my act together and post pics soon - have finally got the stand built and hope to have the hearth done in the next week ot two.

cheers

Salv

[Tim F]

I've made a little more progress on the finishing touches. I made a door out of some sheet metal, by cutting 2 arch shapes to fit the door and attaching them together with a 50mm strip between them. Then I filled the middle with vermiculite and screwed on a handle. Seems to work ok so far but I am already planning another upgrade - but at least I don't have to worry about it catching fire

I also dug out what seemed like 72 tons of dirt and clay, and did a bit of a rough paving job in front of the oven. I have also installed a thermocouple under the dome insulation so the next step is to render the dome - then I can think about the work surface and finish for the base.

[carloswlkr]

beautiful build! congrats! I like the pavers in the floor. must be nice to be firing the oven and eating the fruits of your labour!

[Lavinia]

Hi Tim
I posted you a message this morning but as it was the firt time I have ever psoted here I simply don't know if you received it? that it ever actually went? and where it is now?
Lavinia in Tasmania
writng to you about Convict Ovens.