Homemade Induction Annealer

Bradv86

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I buzzed right by that the board is 36v max. My bad.

The supply is going to output whatever the draw of the system is. It won't autmatically just output 27A and fry the board. You will have some amount of idle current (no brass in the coil) and the load will increase based on the size, material, and location of whatever is put inside of the coil. If you have an ammeter inline in your setup you can probably mitigate issues by inserting brass less and creeping up to more depth and stopping shy of 20A. I don't know how much heat this will generate when approaching the limits of the board, but it should be possible.

My setup is done how hdmunger described, with a 100A relay between my supply and ZVS board. It is controlled by a timed relay on a completely separate 12v supply. It doesn't have to be done this way as you have seen several versions working with other control types.
 

Ryridesmotox

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Its hard to tell from the pics you show, but something else that jumped out at me as a possibility is the timer unit you are using...it looks like it is switching the full output of the power supply into the ZVS board. I don't know what the specs are on the timer, but it may be limiting the throughput to the ZVS is some way and if you upgrade to a larger supply the problem may increase. Using the timer to trigger a beefier relay with a 12 volt circuit may help if that is the case (I assume some of your circuits, fan pump etc., are 12 volt...)

A basic circuit diagram (hand drawn or in Paint) would help diagnosing problem (include specs for each component you used). (here is an example from my build - https://drive.google.com/open?id=16gGj4jPtPGdh--QO44VOZwWJYbIx4TM6)
Fair point... its only rated at 15a 400w

 

hdmunger

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My board is only rated to 36v. I didn't notice that when I ordered or I would have gone with a 48v board.

So I'm thinking about staying with a 24v supply since the 36v supplies seem to be limited to either a 360w, 500w, or a 1kw unit. The 1kw is 27a so I think thats going to be a problem? I honestly don't know what I need to watch for. I have a .6 inch ID coil of 1/8, 9 wraps.

So with a 36v 20a 1kw board, I'm thinking I'll go with a 36v 13.8a 500w supply. Its 140w more than my current supply at +3.8a. Or a 24v supply 20a at 500w. Not sure though. Anyone have any insight?
If you are limited to 36v and 1000w, get a power supply that maxes out all of the metrics that you can - ie 36V 20A which would be in the 720 watt range. (double check the specs on the ZVS board, I would think that they would all be in the normal relation to each other - 36V x 20A = 720W...)
 
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Ryridesmotox

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I buzzed right by that the board is 36v max. My bad.

The supply is going to output whatever the draw of the system is. It won't autmatically just output 27A and fry the board. You will have some amount of idle current (no brass in the coil) and the load will increase based on the size, material, and location of whatever is put inside of the coil. If you have an ammeter inline in your setup you can probably mitigate issues by inserting brass less and creeping up to more depth and stopping shy of 20A. I don't know how much heat this will generate when approaching the limits of the board, but it should be possible.

My setup is done how hdmunger described, with a 100A relay between my supply and ZVS board. It is controlled by a timed relay on a completely separate 12v supply. It doesn't have to be done this way as you have seen several versions working with other control types.
I'll check into that. Right now the only thing I'll gain from changing out relays and switches and stuff is a little less time in the coil for my brass... which, isn't that big a deal to me, so I may leave it as is for a while.
 

pkt1199

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Wanted to share an updated parts list for the "GinaErick" build if anyone wants to go that route. This is a copy of my post on that thread but figured it fits here as well.

Total build price around 650, give or take. The parts list totals around 600 but you'll need misc screws and boards (if building a case) from a local shop in addition to the shipping for the items in the list. I believe the only thing not readily available through my parts list is the shelf and trap door; which were 3D printed with PETG based on the previously shared shelf/door files. For anyone going this route - I've not had any problems with heat from the brass on the printed parts.

I'm thrilled with the results and am now working to find the ideal settings for my various brass. I've attached a couple images and here is a short video link for anyone curious.

GinaErick Annealer.jpg
GinaErick Annealer_2.jpg
 

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Bradv86

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If I was to wire in a relay to get more Watts and Amps to the board... would this be an appropriate unit?

It has the voltage and current rating needed so it should work. I purchased one that was rated for 100A with a 12v solenoid and it works well and has a nice audible click during cycle on/off.

Somewhere someone mentioned that a 2 pole relay would be a better option as it can cut both + and - to the board. I haven't had any problems this far with a single pole breaking the +. YMMV.
 

Ryridesmotox

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It has the voltage and current rating needed so it should work. I purchased one that was rated for 100A with a 12v solenoid and it works well and has a nice audible click during cycle on/off.

Somewhere someone mentioned that a 2 pole relay would be a better option as it can cut both + and - to the board. I haven't had any problems this far with a single pole breaking the +. YMMV.
I'm thinking... if I get a 2 pack, I was thinking i could wire one into each pole.

I'm kinda stuck on the actual electrical side of this too though. Like, if I have a 36v 20a 1000w board, if I use a 36v 22a 800w power supply, is that going to kill the ZVS board? I always hate electrical. I always had someone do wiring in my cars. I can build a beastly stroker motor, but I never got into electrical
 

Bradv86

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It won't outright kill it. If you put something too large in the coil then the supply has enough current to overload and fry the ZVS board. That is why I mentioned an ammeter previously if you wanted to oversize the power supply. Just remember, the more metal you stick in the coil, the higher the current is going to climb, up until the point of board failure since the power supply has more possible output than the board can handle.

hdmunger mentioned earlier, 36v 20a is not 1000w, but only 720w. I think the board has a misprint in the specs somewhere.
 

Ryridesmotox

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It won't outright kill it. If you put something too large in the coil then the supply has enough current to overload and fry the ZVS board. That is why I mentioned an ammeter previously if you wanted to oversize the power supply. Just remember, the more metal you stick in the coil, the higher the current is going to climb, up until the point of board failure since the power supply has more possible output than the board can handle.

hdmunger mentioned earlier, 36v 20a is not 1000w, but only 720w. I think the board has a misprint in the specs somewhere.
Yea, im not sure how much I trust the specs on all this stuff anyway.

I swapped my older 24v 15a 360w power supply to see if there was a difference. So actually, the way I had it wired, the 24v supply melted a case in the same time the 36v 10a 360w supply annealed. It also didn't bog down. According to my buck converter (again not 100% trusting of this stuff) the 24v supply was running cost to 28v just issue and 24v when I hit the button to anneal. So unless, the 36v unit is faulty, the higher amps seems to be putting more energy through the coil and getting it hotter? Not sure if the 36v is faulty or whatever, as that could also be the correct explanation, but I returned it to Amazon.

I'm probably staying with my current setup using the 24v 15a 360w supply. It does what I need it to do for now.

Thanks for the input.
 
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chrispalo

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I will post pictures once I have everything bolted down but I have the 1/8” water cooled version up and running. The pump/reservoir, heat exchanger/80 mm fan, and DC to DC board were all obtained from Amazon. I had to get the 1/8” fittings from McMaster but they arrived in a day.

The small ID of the 1/8” tube does not allow for great flow rate but it is performing very very well even without the heat exchanger fan running.

I ran a 30 second cycle (no fan) and the coil was maybe a few degrees above ambient. Had I done that with the 8 AWG version it would be way too hot to touch. I could feel the return line warming up as it ran. My board is a bit busy now but that’s ok. It’s functioning flawlessly. Once I get everything locked down I’ll change the water to distilled and toss in a dash of water wetter.

Tim
Do you still know what fittings from McMaster?
 

Ryridesmotox

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gcoy19

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I’ll begin by saying my knowledge on this stuff is pretty basic but I had an idea and figured you might be able to tell me if this is possible. I know that in tempering steel some use the loss of magnetic properties as a sign of reaching the right temperature. I also know that as metals reach a certain temp in the coil, the amperage drops (same reason?). So my question is, if this is right, is there a way to quantifiably measure this changeover point accurately enough to find ideal time for annealing cases? I was thinking maybe this is what AMP might be doing with AZTEC? Or am I way off?