Found a weird way to keep my coal fire hot longer without using more fuel

I was working on a big scroll for a gate in my shop and the fire kept dropping temp halfway through each heat. Instead of just cranking the blower, I tried packing a ring of damp clay around the edge of the firepot, about an inch thick. It held the heat in so well I got three more good heats from the same coal charge. Has anyone else used something like firebrick mortar for this, or is clay okay long-term?

2 comments

2 Comments

caleb_coleman881mo ago

Packing a ring of damp clay" is such a smart fix. I would have just stood there staring at the fire getting cold, like an idiot. Do you think regular dirt would work, or does it have to be clay?

baker.willow1mo agoMost Upvoted

My buddy tried regular dirt last summer and it just crumbled away after an hour. Clay holds together because the fine particles stick when wet. Plain dirt has too much sand or organic stuff, so it won't seal the heat in the same way. You really need that sticky, moldable quality.