Annealers

[Bill Wynne]

Reading a thermometer is the check

From the discussion on annealing, it would appear that the only way one
would know if the brass was properly annealed is by testing procedures.

Salt annealing appears to have some merit. However, what test does one use
to determine if the brass has annealed. One cannot use a paint stick in the salt
and see the paint melt at 750F. Therefore, one may have to conduct a vickers hardness
test to determine if the brass annealed properly at some temperature and time frame.

Tunermi, I will first admit I have never annealed anything so I am learning my way through this interesting thread. From what I have learned from reading this is that one needs to raise the temperature of the brass to a desired level. You use a paint stick on the case and then apply a flame and watch the paint strip change at a certain temperature and then you remove the case from the flame. With the salt mix one would watch a thermometer showing the temperature of the melted salt. The brass cases will never get any hotter than the salt so one should give enough time to reach the temperature of the liquid salt (5 to 8 seconds) and then remove them before the heat moves too far down the case towards the base.

 

[Mram10]

I’m not saying you CANNOT put a torch to your brass in a dark room, anymore than I would say you CANNOT ride a bike to work.

Logic dictates, the closer you are to the annealing temperature, the more accurate the annealing will be. If I dip my case necks in a 800f salt bath, the time variable is less important, thus more consistent. If I take a 3000f flame to some case necks, the time variable must be spot on for them to be consistent.

Not sure what testing needs to be done. If I consistently anneal them at the same temp for the same amount of time, the tension should be consistent. It would be interesting to run a test on both ways to see the variance. It is similar to std deviation. Small sd with salt bath. Large with flames.

 

[Mram10]

Tunermi, I will first admit I have never annealed anything so I am learning my way through this interesting thread. From what I have learned from reading this is that one needs to raise the temperature of the brass to a desired level. You use a paint stick on the case and then apply a flame and watch the paint strip change at a certain temperature and then you remove the case from the flame. With the salt mix one would watch a thermometer showing the temperature of the melted salt. The brass cases will never get any hotter than the salt so one should give enough time to reach the temperature of the liquid salt (5 to 8 seconds) and then remove them before the heat moves too far down the case towards the base.

Bill,
It will be easy for you to see the logic. Many have done it one way for so long, they don’t want to change. That’s fine, but to ignore logic makes no sense to me. Good luck and try a few ways so you aren’t ignorant.

 

[brickeyee]

Salt annealing appears to have some merit. However, what test does one use
to determine if the brass has annealed.

tunermi

Time and a known temperature does fine.

It is not all that hard to monitor the temperature of a salt bath rather accurately.

Thermocouples are handy things.

I often use a bare one.

Just a tiny welded dot on the end of the wires.
We used to make them using a Variac and a carbon block.
Twist wires, apply same AC to both wires, other side on the carbon block.
Touch wires to block briefly.

Welded and done.