Stove repair

[hpmer]

My stove is beginning to show cracks, all the way from hairline to some much more substantial.

How can I repair it? I'm wondering if simply pouring clay slip onto and into the crack would work, or should I use the same clay/ash mix I built it from. And should the repair be done when the stove is cold, warm or hot?

Any advice?

[Donkey]

I'll need more info.. Where are the cracks appearing?

Could be that adding a nice, earthen plaster (straw clay and friends) would do it.. Depends on location of cracks and temps involved.
Chances are good that if one particular mix (proportion) cracks, you may need to modify it to continue, more ash, some grog or other fillers.

[hpmer]

The cracks are mostly around the feed tube. It was made with a 50/50 mix of clay soil and ash. The rest of the stove was made was made from furnace cement/perlite. I probably should have made it with brick.

[Donkey]

Ermm.. yeah, I usually make the feed out of brick.. It's one of those high impact areas of the stove.

The danger of just pouring in slip or more of the same mix is that it's likely to just push the cracks open wider.
I've had good luck FIRST using long straw dipped in slip to wrap the feed box with. I'll make a straw/clay wrap about a inch or two thick, with all of the straws aligned horizontally and slicked tight around the feed. Into the straw "strapping" I'll shmeer a wet cob mix (heavy on the sand), worked in well and covering everything. The area around the feed always wants to work itself open, expanding and cracking, the "strapping" helps to keep bricks, cob and whatever else the feed is made out of together.

Once you've got it locked down and not going anywhere further, you can probably just plaster over the cracks and whatnot with a clay/ash/chopped straw mix or something like it.. It'll need to be (either) 50/50 plus straw, or less than 50% clay slip.. Cracking is in indication that there may have been too much clay in the mix.

[hpmer]

Good ideas. Thanks.