what would make handles crack on mugs as they dry

Question:
lately I am having problems with my handles cracking as they dry. it is stoneware clay. My clay was frozen at one time but it has been in a heated area for over a month in bags. Could this be part of the problem? The clay seemed a little dry as I wedged it so I placed a wet rag around in bags and let sit over night and that seemed to help. Really could use your advise.

Answer:
That's a great question and a common one too! I'm guessing it probably isn't because of the clay having frozen, although that can cause problems with your clay, so make sure that you are wedging it really well first. Also, just to test it, you could try what you are doing with some clay that hasn't frozen and see if it works better.

Aside from that, the most common reason that handles crack off is that the clay and the handle are at different stages of drying when the handle is attached. A lot of people forget that clay shrinks as it dries. So if your mug is pretty dry, it has already shrunk quite a bit. If you add a pretty wet handle to that, it is still going to shrink a lot. When it does, it is going to crack away from the mug body.

The way to fix this is to wrap the mug body or the handle in plastic while the other one catches up to similar dryness, then attach the handle.

Another trick is to dry the pot really slowly after attaching the handle. This just helps to equalize any unevenness in moisture between the two. You can even paint wax resist over the attachment points to help with this.

If you're doing it right, you don't need to do the wax, but it can help you until you get the dryness issue worked out.

Finally, when you are adding slip you the pot, add some, let it soak into the clay for 5 minutes, scrape it off and add some more. Then attach your handle. This helps to hydrate the clay on the mug body where you will be attaching the handle.

Hope that helps.

Steve

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