Induction brass annealer redux

[Hollywood]

This is a small sample of the test coils. A slight difference in coil diameter will change the amp draw quite a bit. The 1 1/8 coil diameter and the amount of wraps (8) are what create the best efficiency of the board. It's like a barrel tuner, but in this case it's for all the "boards" that we use.

 

[Skunce]

Gina

Question,
Would the inside diameter of the coil make a difference on what size of cases you are annealing, small case like 22 Hornet -vs- large sizes case like 7 mag etc.

You quoted, "The closer the case is to the coil the higher the current draw. The 1 1/8" diameter was the work of holywood. Took awhile and many tries to get to that right diameter."

Or are you trying to limit/adjust the current draw to a standard set point?

I am attempting to wrap my head around this induction annealing method -vs- the gas annealing method etc.

Tia,
Don

I'm also interested to know how this coil works on small cases. I'm hoping it will work well on my 20 Vartarg cases that were formed from 5.56 LC brass and are difficult to anneal properly with a torch. I'm still waiting on my induction heating board to arrive, so I can't test it myself.
How much odor does this method produce? I've been annealing with propane in the garage mainly because of the odor from the burning propane.

 

[dabeechman]

I'm also interested to know how this coil works on small cases. I'm hoping it will work well on my 20 Vartarg cases that were formed from 5.56 LC brass and are difficult to anneal properly with a torch. I'm still waiting on my induction heating board to arrive, so I can't test it myself.
How much odor does this method produce? I've been annealing with propane in the garage mainly because of the odor from the burning propane.

No discernable odor.

 

[Skunce]

No discernable odor.

I thought possibly some smell from carbon burning out of the neck. More importantly there isn't any CO produced.

 

[Hollywood]

I've done over 600 in one sitting and had no odor noticed. There is only a light puff of smoke for a split second, those were vibratory cleaned. One's the were stainless cleaned I had to look real hard to see any smoke.

 

[Gina1]

Hollywood, could not have explained it any better my self (a picture is worth a 1,000 words. .

Skunce

How it works ? The inductor PCB (printed circuit board) generates a low frequency (100KHZ) RF energy, this a applied to the annealing coil, this energy is induced into the brass case from the coil, and produces what is called "eddy currents" This causes the brass to get hot. Think about bending a wire back and forth and feeling and it get hot. Although we are not bending the brass the rapidly changing alternating current Eddy current) produces the heat in the brass.
I don't think you will have any problem with a smaller case. It's a matter of trial and error. Where you put your case in the coil, if the trap door is movable, start be putting the neck and shoulder in the coil (mid coil)l, watch the current, try to keep it about 12 amps, then work on the amount of time your annealing. Use tempilaq (750 degrees) to see when your brass hits annealing temp.

Hope thi helps

Gina

 

[Terry Altom]

Just saw that Jameco electronics has a shipping program to help defray the cost of the build if needed/wanted. Order more than $25 worth of items, pay their usual shipping ($10 in my case) and receive a coupon code for free shipping on your next order of more than $25 within 90 days. Let's me break the $160 worth of parts from them over a billing cycle or two for no additional shipping charges, which is nice.

 

[Terry Altom]

Gina,

Am I reading that correct as only a 1/2" stroke on the solenoid?

 

[Gina1]

taltom....

Yes, that is correct, as published. It will work extended 2/10's more. Consider this, if your doing 308, 30-06 and in my case 6 Dasher cases, your talking a case head of .47" well within the 1/2" stroke. Larger cases such as the 300 rem ultra mag at .550 are not a problem. For Rev2 in my build I drilled the drop hole 9/16". Trap door worked fine with that. Just remember to put a stop screw( nylon) on the other side of the drop hole to keep the trap door in place. Just position the "L" bracket for the solenoid so that when the solenoid is energized, the trap door clears the trap door hole.
See the picture of this at the beginning of this post.

Good luck

Gina

 

[dabeechman]

taltom....

Yes, that is correct, as published. It will work extended 2/10's more. Consider this, if your doing 308, 30-06 and in my case 6 Dasher cases, your talking a case head of .47" well within the 1/2" stroke. Larger cases such as the 300 rem ultra mag at .550 are not a problem. For Rev2 in my build I drilled the drop hole 9/16". Trap door worked fine with that. Just remember to put a stop screw( nylon) on the other side of the drop hole to keep the trap door in place. Just position the "L" bracket for the solenoid so that when the solenoid is energized, the trap door clears the trap door hole.
See the picture of this at the beginning of this post.

Good luck

Gina

Since I do BMG casings which have a head diameter of .800", I used a bell crank for my trap door. With my design, the arm moves 1"

 

[Gina1]

Since I do BMG casings which have a head diameter of .800", I used a bell crank for my trap door. With my design, the arm moves 1"

Great idea !!!

All of us home workshop "inventors" can add to the GinaErick annearler to make it better.

BTW I was wondering what kind of current you are drawing with that 50 BMG, since the coil diameter was designed for smaller cases, such as the 308 ?? How much of the case neck/shoulder are you putting into the coil ? The neck being .55" diameter, .615" long and about ,012" thicker than the average everyday case.

Much thanks
Gina

 

[Terry Altom]

Gina,

With yourself and Holywood doing all the prototyping I don't think I'll run through so much getting the coil done. Is there any reason this wouldn't work? Also, how prone is this small of tubing to collapsing while turning? Do you see a benifit to filling with fine sand as one other guy mentioned?

https://www.amazon.com/dp/B00UZ9HC2U/?tag=accuratescom-20

Maybe something myself and others need to know is what is the approximate length of tubing required to make the coil? If 72" only makes one, then I'd definitely buy a longer amount.


Thanks,
Terry

 

[Gina1]

Hi Terry

To tell you the truth, in looking at that copper kit, from your link, I don't know having not used it. Would it work ???? Your guess is as good as mine.

All I can refer you to, it what worked for Hollywood and myself. In my parts list, I bought 50' of that 1/8" tubing from Amazon. Way more than needed. Although after a few badly turned coils, I was glad I had the extra.

Using a schedule 40, 3/4" PVC pipe, about 18 inches in length as your mandrel, the copper tubing winds fairly easy, and no sand is needed. The trick is getting it started and keeping the coils even against each other (you can come back after the coil is turned and slightly separate the turns). Also you have to leave enough length to tie into the 1/4" copper tubing that connects to the inductor PCB. A 5 foot length of tubing will do the trick.

Hope this helps

Gina

 

[dabeechman]

Hi Terry

To tell you the truth, in looking at that copper kit, from your link, I don't know having not used it. Would it work ???? Your guess is as good as mine.

All I can refer you to, it what worked for Hollywood and myself. In my parts list, I bought 50' of that 1/8" tubing from Amazon. Way more than needed. Although after a few badly turned coils, I was glad I had the extra.

Using a schedule 40, 3/4" PVC pipe, about 18 inches in length as your mandrel, the copper tubing winds fairly easy, and no sand is needed. The trick is getting it started and keeping the coils even against each other (you can come back after the coil is turned and slightly separate the turns). Also you have to leave enough length to tie into the 1/4" copper tubing that connects to the inductor PCB. A 5 foot length of tubing will do the trick.

Hope this helps

Gina

You are going to be using soft copper tubing. You do not want hard copper tubing (i.e. copper pipe for pneumatics). As such, you do not need to fill it with sand since the soft nature of the copper will bend, not kink. Hard copper tubing would need sand, and even then it can still kink.

Gina,

I use a larger coil now for the bigger case.

 

[Gina1]

debeechman..

I figured you would with the larger case (50 BMG). Just for the folks that might go that route, what is the ID of your larger coil?

Gina

 

[dabeechman]

I haven't quite found one that I am happy with. When I do, I'll post it.

 

[topcat]

if you have the hard copper tube you can just anneal it to make it soft, just stating the obvious

 

[Bucktim]

I've started working on my brass autofeeder for the annealer. I will do a full write up once it is complete. It will have interchangeable plates for case size and the goal is to have it feed a case, via gravity down into the coil. I will probably add a second solenoid that will release the case the same time as the annealer is dropping the annealed one. It will also have a switch/sensor to stop the feeder from turning until the case holder is empty. Current case plate works well for 308 and seems to also work fine with 223. 300Blk did not work, I will have to make a second plate and adjust the drop hole size. Plenty of these diy feeders can be found on youtube, I just took a bunch of their ideas and worked with what I could find.

Check it out and provide suggestions. Thanks

 

[Gina1]

Very nice add-on !!!!!
Your idea for the feed drop solenoid is right on (I think) always takes some fine tuning. You mentioned a feed tube to the coil, I was thinking the same thing a while back. Not for an auto-feed, but just to make it easier to get smaller cases in to the coil. I was thinking a fused glass quartz tube. Strong, heat resistant, and can be bought in various diameters and wall thickness. This link will take you to a company that sells it.
Again great job.

http://www.technicalglass.com/product_pages/fused_quartz_tubing/fused_quartz_tubing.html

Gina

 

[Frog]

Bucktim
That is awesome