Induction heating for case annealing?

[6bg6ga]

I don't know if this belongs in here or not but since this is a case forming/reforming section I thought it would fit right in.

anyway.....

Looking at making an induction heater to aid in annealing case necks of rifle cases. Anyone else used this process? Any thoughts? I've watched the videos of those automatic annealing machines and I'm not really impressed with them. One thing I don't like a torch or a dual torch setup because of the possibility of a torch falling over and starting a fire.

My idea is to construct a simple induction heater with a timed cycle that one can set. Annealing as I understand it is a simple yet understood process. Too much heat and you turn the neck cherry red and possibly case damage to the metal and too little heat and the time you have spent doing the process is wasted. If I understand the process you want to heat the neck to 700-750 degrees. There is a compound out there that can be put on the cases and it burned at this heat point showing that the case is heated correctly. Anyway I'm thinking of a simple unit that would allow one to position the heater above a single stage reloading press and put a case in the case holder and simply run the case up into the heater coil to expose the neck to the heater and cycle the heater and adjust the run to in order to get the correct temp reading. Once that happens you simply lower the case and remove it. The second idea is to construct a simple machine that you load with cases and it anneals them and spits them out.

[ubetcha]

I like that idea. Sounds like it could be done fairly easy. The down side is, of all the induction units I have seen from the automotive tool dealers ( Snap-on, Matco, Cornwell, etc), they are expensive. At least for me anyway. $300 to $400 dollars. But if one could put it on a timed circuit like you stated, the consistence of applying the heat would probably work out great . Some one with electrical circuit knowledge can come up the a timer design I'm sure. I will watch this post with interest.

[btroj]

Even a coil you could just insert the neck into by hand. I prefer to do it that way. Lights off, watch for a hint of glow and pull the case. Once I know the time for that I simply count. By holding the case with my fingers I also ensure the head never gets beyond warm.

How much would a coil run? Is this a battery thing or plug in?

Interesting idea.

[ubetcha]

The ones I saw were plug in a/c voltage.

[6bg6ga]

Even a coil you could just insert the neck into by hand. I prefer to do it that way. Lights off, watch for a hint of glow and pull the case. Once I know the time for that I simply count. By holding the case with my fingers I also ensure the head never gets beyond warm.

How much would a coil run? Is this a battery thing or plug in?

Interesting idea.

This will be a plug in 120vac power supply. It will be a 120 primary transformer with a secondary of 12-24volts with will be rectified to provide DC voltage to run the heater.

[ubetcha]

I was watching some videos that showed induction heat treating and it take just seconds to heat an object in the coils magnetic field

[TheDoctor]

http://youtu.be/a_ohUknmaq4

Just found this. Would be way cool if it could be set up on a presa with a automatic case feeder.

[ubetcha]

There we go! Some one beat us to it. I think it worth a try. But need to get the timer schematics.

[Love Life]

I looked into doing this a year or two back, even started a thread on it in the projects sub forum, but didn't follow through. The price of an induction heater paid for a whole lot of MAPP or Propane and I have been happily and safely annealing ever since.

Here you go: http://castboolits.gunloads.com/show...on-heater-tool

[texassako]

It looks pretty cheap to make one if you know your way around a soldering iron. Here is a pretty simple one: https://www.youtube.com/watch?v=pVYMLnXW9uo and the write up: http://www.rmcybernetics.com/project...ion-heater.htm I might have to add this to my list of future projects.

[dragon813gt]

Neat idea but that's a lot of upfront cost. I wonder what the duty cycle is on the heater? Can't be more than 50%. Most likely a lot lower.

I like the idea and w/ the right jig setup you will have consistency. Basically create a floor that slides out. Drop the brass in from the top. Slide the floor out at the end of the timed cycle. You'd basically just be moving the coil up and down for different case heights. I don't want to stick my hands anywhere near the coil.

I've been eyeing up one of those BenchSource annealers. They're proven, this is not

[Love Life]

Yeah, I just bought some MAPP, 900 degree Tempilaq, 400 degree tempilaq, and went to town. Dumping into a bucket/coffee can of water/citric acid mix removes any scaling and tempilaq and after tumbling you can barely tell the brass has been annealed.

[Doc Highwall]

Here you go with the latest and greatest.

http://www.ampannealing.com/

[GRUMPA]

I think for there $1K asking price.....I'll stay with my Ken Light annealer.....

[dragon813gt]

That's directed at the Benchrest shooter since it only goes up to .338. Price tag will keep most from buying one. It's twice the price of flame annealers. And unless you're shooting for thousandths of an inch I don't see how any added consistency would benefit you.

On the other hand if you don't want to deal w/ open flames and don't mind the cost. Then it seems like a good option.

[s mac]

A diesel eng glow plug would be another possiblity, 12V, relatively inexpensive. Figure out how to duty cycle it, shim the end to fit snugly in the case neck.

[country gent]

We had them available in the tool rooms I worked in to heat bearing to swell them and intall on shafts. Worked good for that and was quicker more consistant than a tourch or oven but they were very expensive units. I think the one was around 600.00 or so. Also keep in mind they dont discriminate between bearings cases rings watches metal chips. Its an interesting Idea and I thought about it once and never went any farther.

[6bg6ga]

Guys it doesn't cost $995 or 600 or even $300 to make this. I've already thought on the timer circuit and have the problem solved. Worried about duty cycle? Don't be because the coil can be cooled via a set of cooling lines a pump and a radiator.

[6bg6ga]

A diesel eng glow plug would be another possiblity, 12V, relatively inexpensive. Figure out how to duty cycle it, shim the end to fit snugly in the case neck.

A diesel glow plug isn't going to work.

[6bg6ga]

It looks pretty cheap to make one if you know your way around a soldering iron. Here is a pretty simple one: https://www.youtube.com/watch?v=pVYMLnXW9uo and the write up: http://www.rmcybernetics.com/project...ion-heater.htm I might have to add this to my list of future projects.

Your part way there. This unit is crude but will work when coupled with a correctly designed cooled coil with a timer and a decent power supply rated at 6A or more.