Steel in oven dome?

[maburton]

Has anyone used any rebar to support the oven dome? I have boo-koos of rebar and angle iron and I was wondering if I put rebar over my dome to support it, would the steel expand with the heat and cause cracks in the oven dome? I thought it may help distribute the heat evenly over the dome? but expansion and contraction could be deadly, or would it?

In addition, I am building a beehive oven. Round brick dome on the outside. would it hurt to support this dome with rebar on top of the insulation but underneath my dome brick veneer?

[gjbingham]

That depends on what "over it" really means when you say "if I put rebar over my dome to support it". Iron will definitely expand differently than firebrick.

[nissanneill]

If you make the curvature correct for the dome height and diameter, you should not need reinforcement.
Somewhere buried in the thousands of posts, I read that if you gold a chain ends the diameter of your oven, and it hangs down the height that you wish your dome to be, then the shape of the chain is the strongest and will be self supporting.
I used a heavy angle iron door frane with lintel bar in my Pompeii, but it is free standing in so far as it can expand at a different rater to the firebricks and move without interference. You can see what I mean at:

http://www.fornobravo.com/forum/f8/n...-1-a-2005.html (Neill's Pompeii #1)

Absolutely no problems but no way would I restrict/reinforce the bricks with steel.
Five minutes after I cemented my keystone bricks into place, I knocked out the sand pattern from the inside if the oven and immediately stood on top of the dome, a cold and wet 90kg. If it was going to collapse then so be it then rather than later.
It goes to show that the information gathered from this forum works and works well.

All the best with your oven.

Neill

[dmun]

Re-bar and refractory are not a good combination. When builders reinforce castable refractory they use special stainless steel needles.

[david s]

I think ordinary steel is prone to corrosion because of the heat, hence the use of ss with refractories.

[TDVT]

This steel isn't embedded in the oven, nor is it a dome, which shouldn't really need buttressing, but the steel frame in the photo is certainly structural in this application.




More pics from the same site

[gjbingham]

Neill,
I like your style. I considered doing that. Get on top of the dome and stress test it right off the bat. Cojones grande!

[david s]

TDVT,
Your setup is typical of that used in brick kilns, but expect corrosion. Could you possibly access these supports for later maintenance ?

[TDVT]

Originally Posted by david s

TDVT,
Your setup is typical of that used in brick kilns, but expect corrosion. Could you possibly access these supports for later maintenance ?

That one's not mine, just something I found online, though the builder, Pat Manley, seems to be well respected.

I wonder about access. In another picture from that set there is a shot of a cross-tie mid point on the channel but I don't think there was any capacity for adjustment there.

I was just throwing that out there in that steel & masonry are not necessarily mutually exclusive.