I was going to make an annealing machine on my CNC mill, but then I thought: why not just make the mill into an annealing machine with a simple fixture. It makes it so much easier to adjust timing and such, all you need to do is change a value in the G-Code, and it's precise to the millisecond. So, now I have the CNC annealer up and running... its rough, there is some chatter in the forward direction. It's because the guide pins are both close to the front. Easy to fix. I'm going to add a case feeder at some point.
Video here:
A dedicated CNC machine would actually be pretty cheap to set-up. The stepper motor can be bought for under $50, as can the motor driver board. The control software is free (Mach 2). All you need to run it is an old PC that has a parallel port (plenty on e-bay) and a power supply. The mechanical parts can easily be made with hand tools.
Tempilaq works well for setting things up. However, as a means of process control, I have come to the following conclusions:
1) Painting the outside of the case gives a false indication, it isn't the temperature of the metal, but of the flame. This stuff should be used on the inside of the neck.
2) I don't see the need for painting 450F or 650F on the body with these machines. The danger of overheating the body is very low since the exposure time is short and controlled. Killing the brass in the neck is where the concern lies.
3) If you want to bracket a temperature, you need two points: "hot enough" and "too hot". The proper way to set up the process is to use one paint that melts at the lowest you want (750F), and one paint that melts just above the highest temperature you want (850F). I'm thinking 875F or 900F. Things should be adjusted so that the low one melts and the high one doesn't at all. I got it so that the 750F melts completely, and the 850F either doesn't melt at all or just a tiny bit at the case mouth does.
The cheapo torches are garbage. These things only have a valve (no regulator) and the pencil flame is not ideal. The Benz-O-Matic JT539 has an actual regulator (keeps the flame consistent as the tank gets lower) and the swirl flame gives better heat distribution.
I have the predecessor to the JT539, the JHT-7. It was the same torch and regulator, but with a hose in between them. It is discontinued, but a lot of places still have stock. The 4' hose is nice. Also, Home Depot has the hoses to convert these torches to BBQ tank for only $16.xx. I need to find a splitter though to connect them both to the same tank.
<span style="font-weight: bold">Update:</span>
Completed a simple case feeder tonight:
Got the JT539 torches on order along with a Y fitting to feed them off of a bar-b-q tank.
Video here:
A dedicated CNC machine would actually be pretty cheap to set-up. The stepper motor can be bought for under $50, as can the motor driver board. The control software is free (Mach 2). All you need to run it is an old PC that has a parallel port (plenty on e-bay) and a power supply. The mechanical parts can easily be made with hand tools.
Tempilaq works well for setting things up. However, as a means of process control, I have come to the following conclusions:
1) Painting the outside of the case gives a false indication, it isn't the temperature of the metal, but of the flame. This stuff should be used on the inside of the neck.
2) I don't see the need for painting 450F or 650F on the body with these machines. The danger of overheating the body is very low since the exposure time is short and controlled. Killing the brass in the neck is where the concern lies.
3) If you want to bracket a temperature, you need two points: "hot enough" and "too hot". The proper way to set up the process is to use one paint that melts at the lowest you want (750F), and one paint that melts just above the highest temperature you want (850F). I'm thinking 875F or 900F. Things should be adjusted so that the low one melts and the high one doesn't at all. I got it so that the 750F melts completely, and the 850F either doesn't melt at all or just a tiny bit at the case mouth does.
The cheapo torches are garbage. These things only have a valve (no regulator) and the pencil flame is not ideal. The Benz-O-Matic JT539 has an actual regulator (keeps the flame consistent as the tank gets lower) and the swirl flame gives better heat distribution.
I have the predecessor to the JT539, the JHT-7. It was the same torch and regulator, but with a hose in between them. It is discontinued, but a lot of places still have stock. The 4' hose is nice. Also, Home Depot has the hoses to convert these torches to BBQ tank for only $16.xx. I need to find a splitter though to connect them both to the same tank.
<span style="font-weight: bold">Update:</span>
Completed a simple case feeder tonight:
Got the JT539 torches on order along with a Y fitting to feed them off of a bar-b-q tank.
