Solder guard putty

Greetings,

I usually use ocher as a heat shield but the putty in the below video looks easy to use. Anyone know what it’s called?

Thank you.
Kind regards,
Lois

If you mean the white goopy stuff he pours over the prongs, that’s soldering investment. Basically a quick setting, heat resistant plaster of Paris. Very useful for setting up a number of small parts at the same time. The quickest way to set up an assemblage of settings.
Just be careful if you solder platinum in plaster. Platinum solder will become brittle because the high heat reacts some way with the plaster (don’t know what the chemistry is). After soldering platinum parts in plaster you have to remelt the solder, which removes the brittleness. You need to set the assembly into something that will hold the pieces in position for the second or two when the solder flows. We used to use powdered asbestos for this. Not so much nowadays.

That might just be casting investment.

Thank you Elliot. Is the plaster hard to remove once the soldering in done?

Best,
Lois

Thank you Shannon. I will look into it.

Best,
Lois

Not too hard. You quench it while it’s still fairly hot and most comes right away. The rest will be blasted off under the steamer.
What takes more time is cleaning up the little bits of plasticene that stick to the mountings once the plaster is hardened. You really need to get all the little bits off or it will be a solder resist and the settings will not have solid joints.

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The other thing you can do with that stuff is put it in and on the gems of a ring you need to melt a wax against to make a matching band. Wax under stones is impossible to get out. The investment takes up that space then can be washed out easily after the wax is melted

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Great tip. Thank you.