It's VERY easy to put together a salt bath annealing station. Here's my setup:
Lab stand, about $25, including burrette clamp. You can probably figure out an equally effective setup without spending that much.
I use an electronic thermocouple thermometer, about $20, plus a stainless steel thermocouple, about $12. You can get bimetallic cooking grill thermometers for around $8-10, and I think they would work as well.
The Lee melting pot can be had for about $40. There are Chinese sources for smaller solder pots that cost less than this. The Lee pot's thermostat is not located within the pot, and that makes it a bit dodgy. I just watch the temperature, and adjust accordingly. Somewhere between about 785 and 825 F works very well. Brass is annealed in 3 seconds flat, and the case head is left hard.
You'll need potassium and sodium nitrate. The smallest quantity I could conveniently get was 1 pound each, total $20.
They make thermocouple temperature controllers for K thermocouples, so you could go that route and not bother with the meter. The ones I've seen do not have enough current switching capacity to run a melting pot, and so would require an external relay.
The molten salt forms a protective coating on the surface of the melting pot, and keeps it looking nice.
It's best to decap before annealing. If you don't you get salt remaining in the case, and get the ugly crust shown in the video.
Brass and the nitrate mixture are compatible. Dunking your brass will not harm it.
