My oven drawings

[MarkJerling]

Mark I have been studying your drawings and they have been most helpful. Thank you.
If you don’t mind I do have a few questions I would like to ask.
1. Advantages of mitreing the bricks in the vault or using square edges and just filling the wide side with refractory mortar so the inside edges are tight?
2: How do you release the arch form?
3. At the thermal breaks you recommend, the grout fills the gap correct?
Well I am sure I will have more questions as I proceed but I must say what an awesome community of builders this site has. A lot of real positive energy in pursuit of a good time. Thank you again for you participation.
All the best, Michelle

You're most welcome.

1. I found mitrerd joints saved me a lot of fire cement. And, in my view, looks better.
2. I made my door arch from heavy cardboard so it could be broken out. Some members make theirs from wood and then the best way is to set it up on wedges so it can be lowered and pulled out.
3. Ideally, nothing should bridge the gap. On mine, the gaps are pretty tight, perhaps too tight, but the floor gap simply fills with a bit of ash.

Happy to help.

[Michele Enrico]

Thanks Mark. I will be starting my own thread soon so you all can follow along and “no no no no not like that” when I get sideways. Haha, great to be a part of the community.
Cent’anni, Michele

[MarkJerling]

I look forward to seeing it Michele!

[Michele Enrico]

Hi Mark. Can you tell me the the preferred radial dimension from center of oven to the outside face of the inner door arch at floor level? I have based my build on your design and do not see that dimension in your plans.
Thanks, Michele

[MarkJerling]

Hi Michelle
For my oven, centre of oven to outside face of inner door arch, on the floor, is 591mm. But, remember,, it can be shorter. Mine's entrance is quite deep.
Kind regards,
Mark

[Michele Enrico]

Thanks that seems short to me with an inside radius of 21” or 534mm. What is the effect if the inner arch is longer? Does it make it hard for the oven to draw?

[MarkJerling]

That set-up gives me a width of 120mm of inner arch, at floor height, and 161mm at the top of the (flat) arch. Some people prefer to have even less. There would be no practical benefit to make it any deeper. I don't believe it should affect the draw, but the shallower it is, the easier it is to work in the oven. Mine's quite deep already, so there would be no benefit in making it deeper.

[Michele Enrico]

Mark, thanks for the feedback. Mine is laying out at 609 mm or 24” to face of inner arch at floor level. That still gives me intersection with the interior dome using a 9” brick at the top of the arch so I think I’m good. Will keep you all posted when I get to that course.

[MarkJerling]

You're most welcome Michele.

[Mr. Slowhand]

Excellent designs, I was more being guided by the force......

[MarkJerling]

Haha. May the force be with you.

[MarkJerling]

I'm amazed how much the oven and it's stand weighs. I've done a few calculations: (All in metric)

The fire bricks are about 1.5 tons and the brick for the base is likewise about 1.5 tons. The suspended slab, in my case a 190mm thick slab to suit the brick module, is likewise about 1.5 tons, without steel. Then there's the fill between the brick layers, so about 1.2 tons. Added to that, the foundation slab itself 4 tons.
9 bags of fire cement at 30kg/bag, so that's another 270kg. And, about 15 bags of regular sand / cement mortar at 25kg/bag, so that's 375kg.

So, all up, including steel and flue it's around 10.5 tons. That means it's about 3 tons per sq/m of footing/base. Or, for the metric challenged amongst us, about 287kg / square foot, or 632.5 lbs / sq.f.