Induction brass annealer redux

[Bora72]

Ciao @oliverpsmile , @itchyTF , @Frog !

Using a snubber, if I understand correctly from the info on the forum and those online, is advisable when using a solid state relay, to be placed in parallel to the power terminals of the SSR.
It's correct?

However, having compared the prices of Amazon with those of AliExpress regarding a 120A SSR relay and a 12v 250A mechanical relay, I decided to purchase both on Amazon since I received the components at home within 1 day, even if I spent a few € more.

Now I have both solutions to try.

If I understand correctly, on the SSR it is advisable to put a snubber on the power terminals.

While on the mechanical relay a schottky diode must be placed on the control terminals.

It's correct?

Which relay do I try first?

This is the mechanical relay:
https://www.amazon.com/Continuous-S...=1699538321&sprefix=relay+12v+250,aps,295&sr= 8-5

This one is similar to the SSR I purchased:
https://www.amazon.com/SSR-120DD-3-...s=ssr+120A&qid=1699538440&sprefix=ssr+120a,ap s% 2C346&sr=8-2-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1

This is the snubber I should buy:
https://www.amazon.com/JESSINIE-Abs...38534&sprefix=snubber,aps,284&sr=8-2-spons&sp _csd= d2lkZ2V0TmFtZT1zcF9hdGY&psc=1

What range, of Ampere, should have the Schottky diode?

Thank you

 

[oliverpsmile]

No snubber, no low cost SSR. I used this contactor for many years without any diode at the control (120 VAC) terminals. Keep it simple - it works.

Amazon.com

Bona Fortuna

 

[itchyTF]

I used the Crydom D1D40 SSR. 100v, 40 amp. There are a few on ebay that are reasonable but I’m not sure I’d trust the ones shipping from china. Wouldn’t know if they are legitimate or knock-offs. There were a few shipping from other parts of Europe.
Didn’t use a snubber and no need for free wheeling diode.

 

[Bora72]

No snubber, no low cost SSR. I used this contactor for many years without any diode at the control (120 VAC) terminals. Keep it simple - it works.

Amazon.com

Bona Fortuna

Ciao oliverpsmile,
your solution is very heavy metal!
Of the ssr break down for another time I use the mechanical relay.
Or of I find silar on the EU at your costa I use your contactor.

Components for the autocostruction are also expensive if you dont have on the house, so are more conveniente and without trouble buy the Annie Annealer by Fluxeon.
It work without trouble at the same price of one discrete autocostruction.

 

[Bora72]

Yesterday night I made some test.
At 46V and 6 seconds I've had this two case with tempilaq.
The coro Is not the same of commerciale Lapua cases?
What I can test for optimizing the annealing?
48V?
More time?
Change the position(height) of the case on the coil?

Thanks

 

[Bora72]

Here Is my tests

 

[Bora72]

Soon I post one photo of the case on the coil

 

[itchyTF]

I wouldn’t worry about the color, it depends on a number of things. A lot of people don’t get the “Lapua look”.

6 seconds seems like a long time.

A color change with Tempilaq only tells you that it got at least that hot, not how hot it got. This thread started with virtually everyone using 750 degrees as the target. It has since been found that 1,000 degrees is closer to where it should be. Dull red in a dark room is a visual indicator that you’re in the zone.

 

[Bora72]

I wouldn’t worry about the color, it depends on a number of things. A lot of people don’t get the “Lapua look”.

6 seconds seems like a long time.

A color change with Tempilaq only tells you that it got at least that hot, not how hot it got. This thread started with virtually everyone using 750 degrees as the target. It has since been found that 1,000 degrees is closer to where it should be. Dull red in a dark room is a visual indicator that you’re in the zone.

The colori of annealing can depend of the clean of the cases?

How I can test of the annealing is made correct?

I've 48V 1200W power supply, regulated for 46V.

6 seconds are the test time, I can refine but I would to find the exact position of the case on the coil First.
I are on error?

1000ºF are about 540ºC

 

[itchyTF]

Can you send a picture of the case in the coil?
Temperature and surface contaminates are a couple of things that can affect color.
Your voltage is fine.
Have you annealed a case in a dark room? If so, what color was the neck of the case?

 

[rox]

I lucked-out last week, finding an industrial pyrometer on eBay at a fraction of the new price. This thing rocks! Super fast and smooth (sends temperature over USB every millisecond), so that spurred me on to try the idea of proportionally controlling a 3kW ZVS (6 HEXFET), by pulling the gates low on a variable mark-space ratio, as proposed by @McFred, @SGK at al. It works brilliantly!

Next steps - implement the pyrometer communication protocol on Arduino, then PID temperature control. Eventually I plan to sit it under a Dillon case-feeder, so everything is derated for continuous operation.

Special thanks to @McFred, @SGK, @BlackICE, @VenatusDominus, @oliverpsmile, and of course, the one and only @Gina1 (and Erick)!

Some further info about components:

• Eltek Flatpack2 rectifier - 48V/3000W. A brilliant, robust, telco-grade power source with CanBUS control and monitoring.
• DC Contactor from Outlander EV - OMRON G9EA-2-CA (a proper DC contactor - AC contactors should be significantly derated for DC use).
• Upgraded version 3000W ZVS, with huge copper tracks.
• Micro Epsilon Pyrometer.

Note: The contactor is only used to connect & disconnect power at the start and end of the cycle (or in the event of alarm conditions); modulation is controlled by taking the HEXFET gates to 0V via schottky diodes, under Arduino PWM control.

This is the pyrometer:



Here is the ZVS running at about 50% duty-cycle:



This is the output of the pyrometer (temperature sensor) - here the ZVS output is being controlled manually using a potentiometer, hopefully this will improve significantly with PID. Note that the work coil is not optimal (this one was made for hardening trigger sears).



The whole messy test setup:




Thanks again to everyone who has contributed.

 

[Bora72]

Can you send a picture of the case in the coil?
Temperature and surface contaminates are a couple of things that can affect color.
Your voltage is fine.
Have you annealed a case in a dark room? If so, what color was the neck of the case?

Hello itchyTF this is the 6,5x47 Lapua case on the coil.
The other photo is of 3 cases with differenti time of annealing.
From left to right 6sec , 5.5sec and 5sec.
I think that the best job is the right case annealed for 5sec.
What do you think?

Tomorrow I post one video of
annealing on the dark room.

Good night!

 

[Bora72]

I lucked-out last week, finding an industrial pyrometer on eBay at a fraction of the new price. This thing rocks! Super fast and smooth (sends temperature over USB every millisecond), so that spurred me on to try the idea of proportionally controlling a 3kW ZVS (6 HEXFET), by pulling the gates low on a variable mark-space ratio, as proposed by @McFred, @SGK at al. It works brilliantly!

Next steps - implement the pyrometer communication protocol on Arduino, then PID temperature control. Eventually I plan to sit it under a Dillon case-feeder, so everything is derated for continuous operation.

Special thanks to @McFred, @SGK, @BlackICE, @VenatusDominus, @oliverpsmile, and of course, the one and only @Gina1 (and Erick)!

Some further info about components:

• Eltek Flatpack2 rectifier - 48V/3000W. A brilliant, robust, telco-grade power source with CanBUS control and monitoring.
• DC Contactor from Outlander EV - OMRON G9EA-2-CA (a proper DC contactor - AC contactors should be significantly derated for DC use).
• Upgraded version 3000W ZVS, with huge copper tracks.
• Micro Epsilon Pyrometer.

Note: The contactor is only used to connect & disconnect power at the start and end of the cycle (or in the event of alarm conditions); modulation is controlled by taking the HEXFET gates to 0V via schottky diodes, under Arduino PWM control.

This is the pyrometer:

View attachment 1492150

Here is the ZVS running at about 50% duty-cycle:

View attachment 1492153

This is the output of the pyrometer (temperature sensor) - here the ZVS output is being controlled manually using a potentiometer, hopefully this will improve significantly with PID. Note that the work coil is not optimal (this one was made for hardening trigger sears).

View attachment 1492154

The whole messy test setup:

View attachment 1492176


Thanks again to everyone who has contributed.

Best work, very best work!

 

[SGK]

I lucked-out last week, finding an industrial pyrometer on eBay at a fraction of the new price.

What did you pay for the pyrometer? I looked for quite awhile for one of these but never found anything priced remotely sensibly for this application.

 

[itchyTF]

Based just on color, 5 sec looks fine. But color is not a good determining factor. Hard to tell from the picture but the coil looks large in diameter. What diameter tubing did you use. The sleeving also looks larger than necessary. Can you take a side view picture?

 

[oliverpsmile]

I lucked-out last week, finding an industrial pyrometer on eBay at a fraction of the new price. This thing rocks!

It really rocks. Congrats!

Super fast and smooth (sends temperature over USB every millisecond), so that spurred me on to try the idea of proportionally controlling a 3kW ZVS (6 HEXFET), by pulling the gates low on a variable mark-space ratio


Next steps - implement the pyrometer communication protocol on Arduino, then PID temperature control. Eventually I plan to sit it under a Dillon case-feeder, so everything is derated for continuous operation.

PID is a serious stuff. Pulling the gates of the ZVS is a discreet control (two stages on/off)***. If PID (proportional-integral-derivative) control is desired, then the power to the ZVS should be the subject - in a close loop system.

Your ambition is really exiting and please keep us posted.

*** My built uses this type of control in a closed loop system.
*** I gave special attention, in the design, in order to minimize the noise in the feed back loop (outside light for example). I'm sure your pyrometer is well focused.

Good Luck

 

[Bora72]

Based just on color, 5 sec looks fine. But color is not a good determining factor. Hard to tell from the picture but the coil looks large in diameter. What diameter tubing did you use. The sleeving also looks larger than necessary. Can you take a side view picture?

How I can test the mechanical quality of my annealing?

The inner diameter of the coil is about 22mm ( 0.866" ), without the thermo isolant I think about 23mm ( 0.9055" ).

Tube used for this commercial coil is 6mm ( 0.236" ) wall tickness about 1mm ( 0.039" ).

What you refere for "sleeving"?

 

[rox]

Pulling the gates of the ZVS is a discreet control (two stages on/off)***.

PWM is only discrete if you are looking fast enough.
The process isn't looking fast enough.
There are 256 levels of output power for PID to play with.

 

[itchyTF]

Testing the mechanical quality is a bit of a challenge. If you had a hardness tester you could compare your annealed brass to commercial virgin brass. Without a tester it is somewhat guesswork. If you get a dull red color for your neck and neck/shoulder junction and not exceed 450 from about mid case to the head, you’re probably OK. If you lightly squeeze the neck and it doesn’t spring back you probably went too hot.

Based on the photos and some guessing, it looks like the inductance of your coil is somewhere around 1.7 to 2 uH. It should be closer to 1uH. I think you would be better served using 1/8” tubing.
Use this calculator to calculate your inductance. Select multi-layer, multi-row.

Coil Inductance Calculator

Use this online calculator to determine the inductance of single-layer and multilayer air-core coils. Both metric and English units of measurement are supported.

66pacific.com

 

[rox]

What did you pay for the pyrometer? I looked for quite awhile for one of these but never found anything priced remotely sensibly for this application.

Roughly 15% of the circa 1k new price.