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Pumice pebbles

Can anyone tell me if one can use kitty litter ( bentonite clay type) instead of pumice pebbles in an annealing pan turntable?

Pumice reflects heat. That is the characteristic you need in a substitute.

For your safety, find out exactly what is in it. A manufacturer might not be able to tell you specifically what’s in their product, especially if you are using their product in a way it was not designed to be used.

Not only can clay vary in it’s chemical composition, but it also can become powdery when exposed to high heat.

Thank you Betty
That is what I needed to hear - taking short cuts in order to save money is counterproductive !

A bag of pumice won’t break the bank.

Here are some alternatives you might not have thought about:

I don’t use pumice much because it’s lightweight and moves. It doesn’t hold any of the pieces I’m soldering in place.

I might use a pan to hold soldering grain which has weight and can hold pieces in place.

A turntable is useful for soldering when the pieces could be displaced when moved, but displacement is not an issue when moving pieces while annealing.

For annealing, I might use several solderite boards, one on the bottom, and some standing up like walls and one on top to hold the heat …to hold the heat in a “cave”.

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If you’d like to try out some pumice, think if you have friends who have horses or raise succulents or cacti. Pumice is an essential ingredient in those kind of potting soils and we gardeners make up our own. I buy mine by the huge bagful at the local feed store, as “Dry Stall”, a horse product meant to be spread in the stall to absorb moisture. It’s under $20 for way more than you’d use in your jewelry studio. So reach out to friends who might already have it.

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Thank you Jon
That is most helpful - I am in Perth Western Australia and Jewellery supply houses are thin on the ground!
AJS are charging nearly $60
I shall go to a garden supply place.

I like the tip about the “cave”
I plan to put a charcoal or magnesia block on top of the pumice.
It is mainly for annealing.

Tbh this is a new area for me. I will watch closely.

Here’s a thread about making a heat cave: Heat Cave on the bench

You could put the charcoal block on top of any kind of soldering board instead of pumice. If you’re concerned about the charcoal breaking, you could wrap it with wire or use some casting investment to hold the bottom of the charcoal block together in a shallow metal tin.

When a soldering board or charcoal block breaks, keep using the broken pieces on top of other boards and surfaces to manipulate the heat. For example, if you are not using a turntable, you can put the small broken piece on the side of your work opposite from the torch side, to reflect the heat back onto your work. You can use the broken piece vertically, by standing it up on it’s side or leaning it against something that’s fireproof.

Use caution when playing with fire and hot accessories. To be prepared for any accidents, I keep within close range a water sprayer, fireproof mitts, a fire extinguisher and something like this:

Wow Betty what an avalanche of info!
Thank you for introducing me to it - so much to follow up on.

Hi Betty
I just re read your tip about the cave and I was wondering what soldering grain is?

Read this thread: Silicon carbide soldering grains

Here are a couple of sources:

I would never understand why so many people and jewelry students continue to use the pumice pan as a soldering station. As a silversmith, I was trained to anneal all metals in a pumice pan. So to put metal on top of pumice, and then flux and then to solder, which often the solder will roll off and disappear into the pumice. I know the lazy susan pan is handy to spin as you are soldering. Pumice was meant for annealing, since it radiants the heat back into the metal. As for soldering, you are better off using a soldering brick or pad. I know, when I teach jewelrymaking, I remove the pumice pans and have my students do their soldering on soldering bricks.

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