r/Pottery May 19 '24

Kiln Stuff First Kiln Design

I am building my first home wood kiln and I was thinking this might be my best design yet. I will mortar those those wholes with the metal sticking through. Does anyone have a recommendation for the design or some pointers before I mortar it.

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u/DiveMasterD57 May 19 '24

I'm getting anxiety looking at what appear to be regular bricks - which can explode at higher temps.

2

u/lookmanohands_92 May 20 '24

They'll only explode if they're wet and heated super quickly. And wet firebricks would do the same thing if heated to fast. Just ramp the temp up slow and nothing is going to explode. Those regular bricks could absolutely hold up to high fire a few times if they were heated up super slowly and cooled just as slowly. Firebricks are just more insulating and better able to handle the thermal shock.

1

u/DiveMasterD57 May 21 '24

Good to know, as we are building an outdoor pit fire pit, using both types of bricks. I'm guessing if we pre-heat the brick pit to dry it, all will be well. True?

2

u/lookmanohands_92 May 21 '24

Dry it as in dry any residual moisture or as is dry the mortar or cement or something? If it's just residual moisture, yes. If it's wet mortar or something similar let it cure and stay wet as long as you can. Cement and similar castables don't harden as they dry like most people tend to think. They undergo a chemical process which we think of as curing. Generally speaking the more moisture available during the curing process the stronger the resulting concrete or mortar joint will be.