Induction brass annealer redux

[hdmunger]

I think the double layer vs. single layer designs (assuming the same number of turns) is the difference in focus of the inductance field...double is more of a donut focusing on just the neck and shoulder, and single is more of a tube which requires the case be set low in the coil to prevent heating of the body, and therefore wastes some of its effect. Just my opinion.

 

[howe0002]

I think the double layer vs. single layer designs (assuming the same number of turns) is the difference in focus of the inductance field...double is more of a donut focusing on just the neck and shoulder, and single is more of a tube which requires the case be set low in the coil to prevent heating of the body, and therefore wastes some of its effect. Just my opinion.

Makes sense. I'll try the 48v ps first and see how that goes.

 

[itchyTF]

I found 1/8” tubing worked fine. Not a lot of flow but sufficient.

I didn’t see a link to his inductance calculator.

 

[Dave M.]

Makes sense. I'll try the 48v ps first and see how that goes.

48V power source works perfect on my setup. I only run single layer coils using 1/4” or 3/16” copper tubing.

 

[Dave M.]

I found 1/8” tubing worked fine. Not a lot of flow but sufficient.

I didn’t see a link to his inductance calculator.

Be careful because I used 1/8” tubing and if you can focus the mag flux just in the top of the shoulder and neck area it works well, if you get too much flux into the brass it will push heat back into the coil and it will start to overheat because you just can’t push enough fluid through the tiny opening to remove enough heat. After 20 cases the coil was so hot on the outside that you couldn’t touch it without getting a flash burn.

 

[Dave M.]

I found 1/8” tubing worked fine. Not a lot of flow but sufficient.

I didn’t see a link to his inductance calculator.

https://electronbunker.ca/eb/InductanceCalc.html

This is what I use and what the video shows as well I believe.
Just remember that model will get you to about +/-10% of actual values which is more than close enough to anneal cartridge brass.

 

[itchyTF]

It’s been quite a while since I used mine (haven’t been shooting) and can’t remember how many cases I ran through at one time but it was quite a few. The coil barely got warm but my aluminum reservoir is fairly large so that would act as a water cooler.

 

[oliverpsmile]

The coil barely got warm but my aluminum reservoir is fairly large so that would act as a water cooler.

Same. I was using a boll, full with water and ice cubes, when I've annealed using a coil. It was cool enough for about 100+ cases .260 Rem. Now days I use Fluxeon coil - no cooling is needed.

 

[ToddP]

I've seen a few posts with the formula for calculating anneal time for a given temperature. I created a spreadsheet showing the times required for various annealing temperatures that may be of interest.

 

[rox]

I've seen a few posts with the formula for calculating anneal time for a given temperature. I created a spreadsheet showing the times required for various annealing temperatures that may be of interest.

Do these times & temperatures achieve stress-relief/recovery, partial recrystallization or full recrystallization?
And whichever it is, can you explain why that option is optimal for us as reloaders?

 

[Fire Dog]

All very interesting, BUT aside from the cost...
Just save up and buy an AMP machine. $1,600 at Creedmoor

Annealing Made Perfect Mark 2 Machine

Annealing Made Perfect Mark 2 Machine Product Information: Larger inductor to suit 50 BMG. Capable of annealing everything from .17 Hornet to 50 BMG. Significantly more output power. Ceramic heat shield in the inductor to aid in heat management. Superior cooling...

www.creedmoorsports.com

They have worked out all the problems in one compact unit that produces consistent annealing without any guess work...
"Shut up and take my money...!"
You burn off one case {only ever once for a given lot and that is often good for most lots of the same quality/brand of brass in that caliber} get a number to use and away you go.
No needing to calculate annealing temp/time {guess work at best..} Just plug and play!
Annealing 30-06 cases in about 8sec and smaller ones faster than that, the code # is good for any other AMP machine as well.
NO water cooling=+
Compact & self contained, sets on a dining room table=++
Quick and consistently repeatable results without guess work=+++

 

[hdmunger]

If that's the way you feel about all of this, then why are you even here?

 

[oliverpsmile]

Do these times & temperatures achieve stress-relief/recovery, partial recrystallization or full recrystallization?

It all depends on where you stop. In a system with closed loop temperature control, the choices are: setting time, temperature or both. With an open direct control one can only set the time. It is possible that the formula that became controversial in this forum, is not that precise. However, the presented graphical plot mirrors the trend of the annealing process. The annealing stop is determined by testing hardness and preventing the entire case from overheating. Basically, if you desire full re-crystallization, in a closed loop system, set the temperature in the flat portion of the shown curve and give additional time to offset some "doubts" in the formula.

Some scientific material was presented in this forum showing that after full re-crystallization the sample does not change for hours if temperature is maintained constant.

My own settings in the closed loop system are: after the case neck reaches 1000F (about 1.2- 1.5 sec - .284 Win) the system maintains temperature at the same level for some additional time, not to exceed a total of 5 sec.

What is optimal for our fellow re-loaders? It's prudent to determine this by a hardness test (100-120 in my opinion) and some shooting experimentation.

Since the shooting accuracy depends on many factors, we should be fully satisfied by any level of re-crystallization of our cases, provided that they are uniform in the entire batch and that they last.

 

[ToddP]

Do these times & temperatures achieve stress-relief/recovery, partial recrystallization or full recrystallization?
And whichever it is, can you explain why that option is optimal for us as reloaders?

I'm the wrong person to ask.

I simply charted out temperatures in 50 F increments using the formula that has been posted at least three times in this thread's 178 pages that we believe shows the time required to anneal cartridge brass. This is in part to dispel the myth that you just need to reach 750 F to get a decent anneal. The chart/graph shows that while you can anneal at 750 F, the time required to do so would be extreme (around 13 minutes). For the times most people want to anneal with, you're best aiming for 950 F or above (5 seconds or less).

There are various supporting documents (such as from AMP) supporting what the chart shows. Unfortunately, those documents are sprinkled among 178 pages of posts in this thread.

 

[Fire Dog]

If that's the way you feel about all of this, then why are you even here?

Curiosity... Just seems like a lot of work to re-invent the wheel {:~/

 

[hdmunger]

I like re-inventing wheels...it is a challenge to both my design/manufacturing skills and my intelect (what little I have, apparently).

Not everyone has the disposable income and the lack of time that the AMP can solve for them. Me, I'm retired on a fixed income, so the unit I paid about $400 in parts to make saved me about $1600 from what an AMP and an AMP-Mate would cost...and gave me a project to fill my time during a winter when I wasn't able to shoot anyways.

 

[itchyTF]

I like re-inventing wheels...it is a challenge to both my design/manufacturing skills and my intelect (what little I have, apparently).

Not everyone has the disposable income and the lack of time that the AMP can solve for them. Me, I'm retired on a fixed income, so the unit I paid about $400 in parts to make saved me about $1600 from what an AMP and an AMP-Mate would cost...and gave me a project to fill my time during a winter when I wasn't able to shoot anyways.

I second this. I’m pretty much in the same boat.

 

[oliverpsmile]

Curiosity... Just seems like a lot of work to re-invent the wheel {:~/

If you were able to read and understand our discussions, development or the principles of this ancient technology of high frequency heating, then you would realize that AMP did not create the wheel. We are all using the same methods of heating. However, our brass feeding developments (allowing full automation) is quite superior to AMP. We do not need to cook the brass and create settings for different calibers , lots etc - our recently developed closed loop (brass temperature feedback) control system allows us to avoid cumbersome keeping track of the "program numbers".

If the intention of your post was to promote AMP sales, this is the wrong place. Unless you are making fun of us - "re-inventing the wheel"...

 

[Frog]

Curiosity... Just seems like a lot of work to re-invent the wheel {

I like re-inventing wheels...it is a challenge to both my design/manufacturing skills and my intelect (what little I have, apparently).

Not everyone has the disposable income and the lack of time that the AMP can solve for them. Me, I'm retired on a fixed income, so the unit I paid about $400 in parts to make saved me about $1600 from what an AMP and an AMP-Mate would cost...and gave me a project to fill my time during a winter when I wasn't able to shoot anyways.

Same reason I built mine

 

[ToddP]

It's well worth watching Reese's latest video, particularly if you are of the view that 1.9s is "gospel". Personally I wouldn't size after annealing so I think his last test scenario isn't valid/appropriate. But note just how soft the 1.9s brass was versus, for example, where Norma anneals its brass to during production (which would equate to somewhere between 1 and 1.5 seconds in his tests - for which he did specifically says he was unsure of temps but I think we can assume he was at least trying for 1000F given the previous video). It is good that, one way or another, he had access to a Vickers hardness tester (although admits it wasn't his).

This video seems to be behind a paywall for me.
Maybe you could give us a summary of what it says?

Here is a video where a guy found an "inexpensive" way to test brass hardness (near the end of his video). There is a tool on Amazon ( https://www.amazon.com/dp/B07BNCJ7C...KMLMANYK&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it ) that will test metals hardness. The best use is to measure the hardness of unfired brass, then attempt to achieve that same hardness through annealing after having shot the cartridge. He scored the tester for £35, but it normally sells for $300+.

This might create an opportunity for someone's side job: case hardness testing for the rest of us at a reasonable price (as you only have to cover time, shipping, and the $350 of the device).