Induction brass annealer redux

[bertn]

Downloaded tinycad and tried to draw the circuit, see below.
I left out the 12vdc loop with timer, shunt etc. since this is working fine.

I also replaced the induction board load by the heaviest load I could find, a 120v paint stripper to see if that would run.
Was running fine (although 1/3 of the power it normally runs of course) with the following va meter readings;
standby 40.3v 0.37a
paint stripper running 38v 3.44a

Anywone know what else I could attach to simulate a load comparable to the induction board to test the power supply?
Is there a way to test my induction board?

here is a pic of the transformers and line filter.As you can see it was not all wired up back then but now there is so much in the way (build the box too small...) that it's hard to capture it now.

 

[FishinDog]

Downloaded tinycad and tried to draw the circuit, see below.
I left out the 12vdc loop with timer, shunt etc. since this is working fine.

I also replaced the induction board load by the heaviest load I could find, a 120v paint stripper to see if that would run.
Was running fine (although 1/3 of the power it normally runs of course) with the following va meter readings;
standby 40.3v 0.37a
paint stripper running 38v 3.44a

Anywone know what else I could attach to simulate a load comparable to the induction board to test the power supply?
Is there a way to test my induction board?

here is a pic of the transformers and line filter.As you can see it was not all wired up back then but now there is so much in the way (build the box too small...) that it's hard to capture it now.

View attachment 1001025

View attachment 1001029

At first glance it's always good practice to connect the "-" lead to a relay to reduce chance of welding the contacts. For an increased load test; maybe a toaster oven? Uses induction for the heat strips. Never took one apart but maybe they use DC volts after a rectifier and you could connect direct to the heat strips.

 

[bertn]

At first glance it's always good practice to connect the "-" lead to a relay to reduce chance of welding the contacts. For an increased load test; maybe a toaster oven? Uses induction for the heat strips. Never took one apart but maybe they use DC volts after a rectifier and you could connect direct to the heat strips.

I will swap the relay wires to the negative then.

Also have a toaster oven I bought for powder coating bullets in the future so I will give that a try and post the results.
It's ac i'm 100% sure.

Thanks.

 

[Gina1]

Downloaded tinycad and tried to draw the circuit, see below.
I left out the 12vdc loop with timer, shunt etc. since this is working fine.

I also replaced the induction board load by the heaviest load I could find, a 120v paint stripper to see if that would run.
Was running fine (although 1/3 of the power it normally runs of course) with the following va meter readings;
standby 40.3v 0.37a
paint stripper running 38v 3.44a

Anywone know what else I could attach to simulate a load comparable to the induction board to test the power supply?
Is there a way to test my induction board?

here is a pic of the transformers and line filter.As you can see it was not all wired up back then but now there is so much in the way (build the box too small...) that it's hard to capture it now.

View attachment 1001025

View attachment 1001029

Looking at your schematic.. You have no filter capacitors. I'm not sure about the picture, those 2 black items on ether side of the coil ..could be filter capacitors? But they do not look large enough, for the power draw for this PCB. If you are missing caps, you would be applying 120 cycle pulsating DC to the inductor board. Wont work. Needs to be solid DC for the inductor PCB to start oscillating at the moment the solid DC power is applied through the power relay to the PCB.
JMHO Gina

 

[Gina1]

It's a Nomad 883Pro from http://carbide3d.com
View attachment 1001026

Very nice !! Your build shows it.

 

[bertn]

Looking at your schematic.. You have no filter capacitors. I'm not sure about the picture, those 2 black items on ether side of the coil ..could be filter capacitors? But they do not look large enough, for the power draw for this PCB. If you are missing caps, you would be applying 120 cycle pulsating DC to the inductor board. Wont work. Needs to be solid DC for the inductor PCB to start oscillating at the moment the solid DC power is applied through the power relay to the PCB.
JMHO Gina

Yes I think they are capacitors, on them is listed 2.2 uf 275v but that is on the filter before the transformer.
Indeed no capacitors after the transformer.
Any advice on what capacitor to add and where to get rid of the 120 cycle pulse?
I have a few salvaged ones so hopefully they are useful.

By the way I added more load to the transformer to test the voltage drop at a higher load.
So now I have attached a toaster oven AND a paint stripper AND a water heater element.
It's working perfectly fine and getting the following meter reading;
standby 40.5v 0.40a
with load 35.7v and 8.15a

 

[FishinDog]

Yes I think they are capacitors, on them is listed 2.2 uf 275v but that is on the filter before the transformer.
Indeed no capacitors after the transformer.
Any advice on what capacitor to add and where to get rid of the 120 cycle pulse?
I have a few salvaged ones so hopefully they are useful.

By the way I added more load to the transformer to test the voltage drop at a higher load.
So now I have attached a toaster oven AND a paint stripper AND a water heater element.
It's working perfectly fine and getting the following meter reading;
standby 40.5v 0.40a
with load 35.7v and 8.15a

Might be worth hooking a car battery up to your induction board just rule it out. Be sure to keep a fuse in your test circuit

 

[bertn]

Might be worth hooking a car battery up to your induction board just rule it out. Be sure to keep a fuse in your test circuit

Thanks good idea. Charging the battery for my trolling motor now.
Will post results.

 

[bertn]

Thanks good idea. Charging the battery for my trolling motor now.
Will post results.

Update:
Ran it with the battery; Same problem
Voltage dropped immediately to next to nothing, amps ramped up like crazy and fuse (25a time delay) blew.

I'm a bit reluctant to use higher rated fuse since ebay add states
"Although this circuit can tolerate 20-30A input current moment, but do not exceed 15A when safe work"

The problem has to be the induction board, I'm out of fuses now so that's the testing for today...

I will disassemble it from the case and hope one of you can give me some pointers on how to troubleshoot the induction board.

 

[GrocMax]

If the induction board is not 'firing off' and the tank circuit doesn't start I think this is the behavior you'll see. Try the large capacitor idea across the DC output lines, it may take more of an inrush than the PS can supply to power it up and get the tank circuit resonating.

But go ahead and inspect the induction board see if the mosfets are in one piece. Seen several videos of people trying to operate these things off a 12v battery, they just pop the mosfets.

Watch this particularly from about 6 minutes in, explains why it needs a very fast rise time (capacitor discharge) to start.

 

[bertn]

If the induction board is not 'firing off' and the tank circuit doesn't start I think this is the behavior you'll see. Try the large capacitor idea across the DC output lines, it may take more of an inrush than the PS can supply to power it up and get the tank circuit resonating.

But go ahead and inspect the induction board see if the mosfets are in one piece. Seen several videos of people trying to operate these things off a 12v battery, they just pop the mosfets.

Thanks for the links!
The mosfets still look normal. Also have not smelled anything weird. The fuses hopefully saved my mosfets.

I thought that the relay would be enough to switch the power on fast enough but the second video you posted made clear the difference with or without a capacitor.
So I will definitely need a capacitor. Would you or someone else be able to point me in he right direction what size/specification of capacitor I need?

Thanks again, I'm very grateful for the help from all of you!!

 

[GrocMax]

What kind of big ones do you have laying around? A couple hundred uF or bigger polarized electrolytic of at least 150v DC would be my guess, but I'm sure someone here could advise you better.

 

[bertn]

What kind of big ones do you have laying around? A couple hundred uF or bigger polarized electrolytic of at least 150v DC would be my guess, but I'm sure someone here could advise you better.

The biggest ones I have that are polarized are marked 200v 680uf 85c.
I have two of those and they are about an inch in diameter and 1 1/4 inch high.

 

[FishinDog]

Here's the updated drawing per my "as built". PM me if you'd like the TinyCad file. I'm also working the final parts list and can include that when complete. Still working on the hopper; need to machine a few parts on my mini CNC.

View attachment 1001018

Here's my parts list. Mostly identical to Gina1's original with different 48vdc power supply from GrocMax (has voltage and current limiting features), added the recommended OPB100Z sensors and also a few other components for current and PLC control. Not showing the LEDs as I just pulled them out of a grab bag I had. Also, the original solenoid from Jameco is no longer available. I listed one in the Amazon list; hope to use it with my hopper release. Let me know if you have any questions .

Many thanks to Gina, Erick, GrocMax and many other contributors; you guys rock and I never could have done this without you!

www.Jameco.com
Jameco Part Number Description Quantity Unit Cost
16652 AC RECEPTACLE,MALE,15A@250V 1 $1.09
34462 VARISTOR(MOV),130VAC (S20K130) 1 $0.29
36011 @ DIODE,SIL REC,1N4007,1A, 100 10 $0.12
38050 PWR CORD,6',18AWG/3COND,SVT, 1 $4.95
69439 FUSE,AGC FAST ACTING,3A,250V, 4 $0.35
69570 FUSE,MDL SLOW BLOW,10A,250V, 1 $0.59
105102 PROTOTYPE BUILDER,1.5"x3.5" 1 $5.95
196817 "Fan Guard 120mm 4.68" PLASTIC" 2 $2.19
264990 KNOB,1/4 SHAFT,19.8MM,JK-901D, 1 $0.99
317825 SWITCH,TOGGLE,R13-25A2-01, 1 $2.55
323337 PWR SPLY,SW,ENCL,36W, 12V@3A,U 1 $12.10
690945 @ RES,CF,2.2K OHM,1/4 WATT,5%, 10 $0.099
1711947 FUSE HOLDER,PC BRD/W TERMINALS 5 $0.99
2172148 PWR SPLY,SW,ENCL,753W,48V@15.7 1 $169.00
2217756 FAN,12VDC,102.4CFM,120X120X38 2 $9.95

amazon.com
E-Projects EPC-103 Resistor Kit 1 $10.79
Yosoo 12VDC Water pump&tank SC-300T 1 $22.03
SainSmart 1000W ZVS Low induction heating board 1 $37.99
Packard C230B 2 Pole 30 Amp Contactor, 120 V Coil 1 $9.00
AGPtek® 12 Pipe Aluminum Radiator for PC CPU 1 $16.99
uxcell 5pcs 600V 25A Dual Row 6 Pos Terminal Strip 1 $8.99
DROK Digital Voltage Current Volt Amp Panel Meter 1 $8.00
Sestos Digital Quartic Timer Relay Switch 2 $29.96
2pcs 22mm DPST Momentary Push Button Switches 1 $7.40
Potentiometer, PEC guitar amp, 5K Linear 1 $10.95
OPB100Z Optical Switches 2 $14.68
Refrigeration Copper Tubing, 1/8" x 50' 1 $22.19
Du-Bro 785 1/8" Tubing Bender 1 $11.83
Uxcell JF0730B Linear Pull Solenoid DC 12V, 300 mA 3 $9.16
Uxcell a14051000ux0270 1% Resistor, 39 Ohm 1W 1 $6.12
Electronix Express- Hook up Wire Kit 22 Gage 1 $20.95

velocio.net (Programmable Logic Controller)
Ace 11 - 6 digital in, 6 digital out 1 $49.00
Relay5A- Relay (5 Amp) 1 $19.00
Wall Plug - 5 volt, 2 Amp. 1 $9.00
vProg6 - 6 Foot Programming Cable 1 $5.00
Termination - Screw Type 1 $9.00

 

[GrocMax]

The biggest ones I have that are polarized are marked 200v 680uf 85c.
I have two of those and they are about an inch in diameter and 1 1/4 inch high.

Heck give it a shot, put one between the rectifier and the relay across the DC supply + and - so it charges up when the PS is on and discharges into the induction board on contactor close. Once the tank circuit is resonating on its own the voltage and current can come down on the induction board to some fairly small levels.

Guy in the last video uses a BIG one on his homemade unit. Maybe ask him how big he needed to go to get it to fire off right.

The switching PS we are using don't have huge caps in them, but they seem to fire it off just fine, you may not need a big one like the homebuilt unit in the vid.

I guess I should state the obvious though, polarized capacitor needs to be connected with the proper polarity or it can go kerblooey.

 

[normmatzen]

Bertn,
By your schematic, it looks like you have a coupled inductor in series with both the 40 V and ground leg of the supply. That would be a classic way of arcing the relay contacts as inductors abhor a current change and will increase voltage from its inductance charge till current continues to flow even if it means an arc. You would be better off with a filter capacitor across the bridge output and take out the inductor.

 

[bertn]

Bertn,
By your schematic, it looks like you have a coupled inductor in series with both the 40 V and ground leg of the supply. That would be a classic way of arcing the relay contacts as inductors abhor a current change and will increase voltage from its inductance charge till current continues to flow even if it means an arc. You would be better off with a filter capacitor across the bridge output and take out the inductor.

Thanks for your input.
i will replace it by a capacitor.
I put it in as a choke to reduce ac ripple so clearly not a good choice then.
Any advice on what filter capacitor i need?
Thx.Bert

 

[Chet58]

So I just completed my GinaErick case annealer. I just followed the instructions on the first page of this post and used the parts list to create my version. Electronically it is exactly the same as the original. Why mess with a working formula. Beside my area is mechanical rather than electrical.

The enhancement I made was on the trap door system and added a case guide. The trap door system is on a platform that can move up and down to adjust for case length. One I have the height adjustment for a particular caliber I can mark the location of the indicator on the side of the housing. This just makes for more consistent application of the location. I can quickly move the platform up or down using the hand wheel located next to the coil. The platform moves up and down using a lead screw and linear guide bearings. This allows the case neck to be presented to the coil for everything from 6PPC to 338 Lapua. Once you have the timer adjustment and the platform height defined you can go back to the same settings in just a few seconds with no guess work each time you setup.

The other enhancement was to add a UHMW bushing to guide the case to the trap door. Bushing were made from bar UHMW and bored to the size of the case. Since the exposure to heat is only coming from the case neck the bushing are not having any problem surviving at all. For this I bored the hole for the case out to 3/4" to carry the UHMW busing. All of the bushing measure 3/4" dia OD with a thru bore to match the case size. Cases drop out the front into a small metal baking pan.

The entire unit measures 8" wide, 19" tall and 18 inches deep. Attached are a few images of the completed unit. Just wanted to share my experience. This is an awesome little annealer!!! Cost of the project was some place around $500. Guts of the project were around $300. The case, bearing and leadscrew drove the cost of the project up. I know other are using PC cases which is keeping cost much lower but I like the industrial look of this type of enclosure.

Besides none of us have gotten into this hobby to "save" money.

 

[Gina1]

So I just completed my GinaErick case annealer. I just followed the instructions on the first page of this post and used the parts list to create my version. Electronically it is exactly the same as the original. Why mess with a working formula. Beside my area is mechanical rather than electrical.

The enhancement I made was on the trap door system and added a case guide. The trap door system is on a platform that can move up and down to adjust for case length. One I have the height adjustment for a particular caliber I can mark the location of the indicator on the side of the housing. This just makes for more consistent application of the location. I can quickly move the platform up or down using the hand wheel located next to the coil. The platform moves up and down using a lead screw and linear guide bearings. This allows the case neck to be presented to the coil for everything from 6PPC to 338 Lapua. Once you have the timer adjustment and the platform height defined you can go back to the same settings in just a few seconds with no guess work each time you setup.

The other enhancement was to add a UHMW bushing to guide the case to the trap door. Bushing were made from bar UHMW and bored to the size of the case. Since the exposure to heat is only coming from the case neck the bushing are not having any problem surviving at all. For this I bored the hole for the case out to 3/4" to carry the UHMW busing. All of the bushing measure 3/4" dia OD with a thru bore to match the case size. Cases drop out the front into a small metal baking pan.

The entire unit measures 8" wide, 19" tall and 18 inches deep. Attached are a few images of the completed unit. Just wanted to share my experience. This is an awesome little annealer!!! Cost of the project was some place around $500. Guts of the project were around $300. The case, bearing and leadscrew drove the cost of the project up. I know other are using PC cases which is keeping cost much lower but I like the industrial look of this type of enclosure.

Besides none of us have gotten into this hobby to "save" money.

View attachment 1001297 View attachment 1001298 View attachment 1001299 View attachment 1001300 View attachment 1001301

Nice build !!!! Looks great. As I've said before "this is everyone's build" Love your enhancements.
Just for my curiosity, since your build is the basic circuit, how much current are you pulling without a case in the coil ? Most everyone with the basic circuit is 8.6 amps. Just want to compare.
Thanks

Gina1

 

[bertn]

Wow Chet, that is quite the machine,
Its looking great!
It definitely shows your mechanical background.