How to deal with a crack

[manumit]

Any suggestions on how to deal with a good sized crack? It showed up as soon as I started curing fires. I didn't, "go big or go home", but it cracked pretty quickly. It is right at the front of the oven running back through the arch and chimney mount. When the oven is warm at all it is probably a full millimeter wide. It's wide enough smoke can come out of it. The brick at the front doesn't really even feel warm to me when it is going so I was wondering if it could have anything to do with the oven warming and expanding and the front not expanding at all.

I've had no other cracks that I can see.

Do I take a grinder and cut the joint out and redo it? Would that make a difference? Any suggestions would be welcome.

[david s]

It probably won't get any worse, but will open every time the oven heats up. My guess is that it's caused by the inner parts of the oven heating, expanding and putting pressure against the cooler outer parts. An expansion joint between the inner and outer oven parts usually prevents cracks in the front arch, but too late to add one now. Repairs of these cracks are invariably unsuccessful in my experience, but if you want to give it a shot, wet the crack well, wait 10 mins for the water to soak in, then paint a thin slurry of cement and water into the crack, wait another 10 mins and fill the crack with 4:1 fine sand and cement mortar. Then try to keep the area damp for a few days and wait at least a week before retiring. The problem is that the oven will still want to expand in the same place. If it were mine I'd leave it. Remember there are ovens with cracks and ovens with owners who lie about their ovens having cracks. Don't over worry it the oven won't fall down.