OTE fire box grates

[reck9953]

I’m getting ready to build an OTE & I’m wondering what people use for the grates in the fire box? Thanks

[Johnny Yooper]

I used some 3/4 inch dia. rebar and made some upside down "U" supports the width of the fire box; I scrounged chucks of grates from various stoves that were getting junked and set the grates on top of the U supports. Don't forget to plan for Air Under Fire, best modification I did to my oil tank stove.

[maple flats]

Others have used a whole bunch of grate options. They are often made using 1/4" stock 1.5 or 2" angle iron. If using that idea, have the V look like this VVVVVVVV with about 1/4-3/8" between each piece of angle iron. The V's then fill up with ash and that ash protects the angle iron from the intense heat. Others have used cast iron pieces or angles, others used round pipes, but I see no way to protect the pipe. There may be more ideas too.
Some have blocked up and made holes in a concrete floor so air can blow up thru it. I think that wants a good refractory cement.

[billschi]

So far I welded up some 1/2" rebar. It only lasts one season. I may try stainless steel next season.

[Cjadamec]

The angle iron welded into the VVVV pattern works remarkably well and you don't need heavy steel to do it. I used angle iron from a cut up bed frame, which is about as cheap as angle iron gets, for the grates in my evaporator and it's still as strait as the day I welded it together. Between the ash in the groves and the AUF blowing cool air on the grate everything held up much better than I expected.

[Hunt4sap]

CJ, do you have any pictures of the inside bottom with angles/ AUF in your OTE?
I'm getting ready to to this same grate and looking for some people's different setups...

[raptorfan85]

I used 1 inch solid bar stock, supported with 1/4 angle iron on the ends. If they dont hold up i will probably try the angle iron v pointing up.

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[Cjadamec]

Here is a shot of the grates this was taken late into last season after many long hours of fireing the evaporator. I never thought those cheap little angle iron pieces would hold up but I made it like the people here said to make it. I was very happy with the results.

[maple flats]

I used 1 inch solid bar stock, supported with 1/4 angle iron on the ends. If they dont hold up i will probably try the angle iron v pointing up.

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When you build new, do not have the angles point up, you want the points down, they then fill up with ash which is what protects them from the intense heat. I hope that is what you meant. If you have the points up the ash will try to plug the spaces between them that you need for air flow and they will soon sag. While I did not make them, my grates are factory and they look like angle iron in shape with the points down to fill with ash. They are still perfect and the arch is from 2001. I forget now, the grates are in sections and I think the sections are as if they are 3 V's each, V pointed down and an air space between each, but they are cast.

[littleTapper]

I filled my V angle iron with refractory cement. Still perfectly straight after 4 seasons. I think I have a 1/2" gap between; might be 3/4". It breathes well.

[raptorfan85]

When you build new, do not have the angles point up, you want the points down, they then fill up with ash which is what protects them from the intense heat. I hope that is what you meant. If you have the points up the ash will try to plug the spaces between them that you need for air flow and they will soon sag. While I did not make them, my grates are factory and they look like angle iron in shape with the points down to fill with ash. They are still perfect and the arch is from 2001. I forget now, the grates are in sections and I think the sections are as if they are 3 V's each, V pointed down and an air space between each, but they are cast.

That is what I meant... Worded it wrong. The open side up, point down.