J Tech Laser - compatibility question

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DocsMachine
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Re: J Tech Laser - compatibility question

Post by DocsMachine »

I'm not at all sure that most home-shop type laser power supplies can vary the power level "on the fly". I may very well be wrong about that, but I was given to understand that there was little reason to try and vary the power during the cut, when it's considerably easier- and more precise- to vary the traverse speed.

The typical and very common Chinese "K40" laser engravers generally have the output-power setting wholly separate from the activation signal. That is, you set the power to the desired level beforehand, and then the controller will fire it as needed to produce the image or cut.

I'd be curious to know if the typical home-shop laser can vary the power 'on the fly', and if it can, what benefit it would have.

Doc.
eswakon@eas-eng.com
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Re: J Tech Laser - compatibility question

Post by eswakon@eas-eng.com »

Kieth or others. What other machine, if any, does an acorn board resemble? I found potential postprocessors for a laser, but don't know which to choose from. https://jtechphotonics.com/?p=3851

Any help selecting would be appreciated. Thanks
mikes
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Re: J Tech Laser - compatibility question

Post by mikes »

cnckeith wrote: Wed Jun 26, 2019 10:42 am Future plans for Acorn PWM are to pipe a 5 vdc PWM output to pin 14 on the DB25
and create two parameters to control the base frequency and duty cycle of the PWM to facilitate easy variable power control of Laser modules via Gcode. This is a new software feature (hardware is in place) and when available will work on all Acorn Hardware.
Nice! I am continually impressed with the interest in adding cool features. This will make integrating a PWM laser module much easier.
martyscncgarage
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Re: J Tech Laser - compatibility question

Post by martyscncgarage »

eswakon@eas-eng.com wrote: Fri Jun 28, 2019 1:09 pm Kieth or others. What other machine, if any, does an acorn board resemble? I found potential postprocessors for a laser, but don't know which to choose from. https://jtechphotonics.com/?p=3851

Any help selecting would be appreciated. Thanks
Maybe you can get Jtech to get in touch with Keith to get an Acorn and work with it to develop running one of their lasers?
:)
Reminder, for support please follow this post: viewtopic.php?f=20&t=383
We can't "SEE" what you see...
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mikes
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Re: J Tech Laser - compatibility question

Post by mikes »

DocsMachine wrote: Fri Jun 28, 2019 3:44 am I'm not at all sure that most home-shop type laser power supplies can vary the power level "on the fly". I may very well be wrong about that, but I was given to understand that there was little reason to try and vary the power during the cut, when it's considerably easier- and more precise- to vary the traverse speed.

The typical and very common Chinese "K40" laser engravers generally have the output-power setting wholly separate from the activation signal. That is, you set the power to the desired level beforehand, and then the controller will fire it as needed to produce the image or cut.

I'd be curious to know if the typical home-shop laser can vary the power 'on the fly', and if it can, what benefit it would have.

Doc.
The K40 is a CO2 based laser, which uses a high voltage PS. The LED based lasers are typically powered with a 12v DC PS. The diode based lasers are typically variable power, and are control via PWM. I think by varying the power you can creating gradients for images and complex logos. Being able to lightly "toast" to fully blacken a material gives lots of options when trying to "burn" an image.

Funny - The CO2 lasers are much higher wattage then currently possible with LED, but the LED lasers are much more dangerous due to the visible wavelength they use. Scatter from a CO2 laser will typically not harm you. Scatter from a visible spectrum LED laser will instantly create a permanent blind spot in your vision. These things look like fun and are cheap enough, but you need to take precautions.
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Re: J Tech Laser - compatibility question

Post by DannyB »

Ken Rychlik wrote: Thu Jun 27, 2019 11:43 pm turning it on and off is an easy task. Getting it to burn hotter when you are going fast and not as hot when you run slow is the interesting part. I would think a plc that tapped into the step signals of the x and y would be enough info. Then turn on the laser with each step, or every ten steps, ect.... so when you go fast, there are more steps and more heat. running slow is less steps, so less heat. Machines slow down on the corners or changing direction, so it would burn the part during that time, if it's not adjusted with machine moves.
You don't need a plc
The c# interface can read the position and speed from cnc12 directly.

(I have a digitizing laser from optimet that is hooked up this way)
eswakon@eas-eng.com
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Re: J Tech Laser - compatibility question

Post by eswakon@eas-eng.com »

cnckeith wrote: Wed Jun 26, 2019 10:42 am Future plans for Acorn PWM are to pipe a 5 vdc PWM output to pin 14 on the DB25
and create two parameters to control the base frequency and duty cycle of the PWM to facilitate easy variable power control of Laser modules via Gcode. This is a new software feature (hardware is in place) and when available will work on all Acorn Hardware.
Any update on this release?

I've been able to get my laser working with on/off only using M10px & M11px commands (x is the relay board port number). I turn a fan on/off with the M3 & M5 commands. I modified a post processor to make this all work. see attached (I added the .txt to allow it to upload. You need to remove that so the file extension is .pp - save that post processor file in your vetric postP folder - C:\ProgramData\Vectric\VCarve Pro\V9.5\PostP on my machine. It will then show up as a post-process in the drop-down list.

You also need to add the port assignment for the M10/M11 and M3/M5 to the wizard.
Attachments
Centroid_Arcs_inch-laser-v6.pp.txt
(4.18 KiB) Downloaded 142 times
martyscncgarage
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Re: J Tech Laser - compatibility question

Post by martyscncgarage »

eswakon@eas-eng.com wrote: Mon Jul 22, 2019 6:19 pm
cnckeith wrote: Wed Jun 26, 2019 10:42 am Future plans for Acorn PWM are to pipe a 5 vdc PWM output to pin 14 on the DB25
and create two parameters to control the base frequency and duty cycle of the PWM to facilitate easy variable power control of Laser modules via Gcode. This is a new software feature (hardware is in place) and when available will work on all Acorn Hardware.
Any update on this release?

I've been able to get my laser working with on/off only using M10px & M11px commands (x is the relay board port number). I turn a fan on/off with the M3 & M5 commands. I modified a post processor to make this all work. see attached (I added the .txt to allow it to upload. You need to remove that so the file extension is .pp - save that post processor file in your vetric postP folder - C:\ProgramData\Vectric\VCarve Pro\V9.5\PostP on my machine. It will then show up as a post-process in the drop-down list.

You also need to add the port assignment for the M10/M11 and M3/M5 to the wizard.
Laser support is being kicked around, but it is my understanding Plasma support is going to be developed first.
Hang in there!
Reminder, for support please follow this post: viewtopic.php?f=20&t=383
We can't "SEE" what you see...
Mesa, AZ
mikes
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Re: J Tech Laser - compatibility question

Post by mikes »

eswakon@eas-eng.com wrote: Mon Jul 22, 2019 6:19 pm
cnckeith wrote: Wed Jun 26, 2019 10:42 am Future plans for Acorn PWM are to pipe a 5 vdc PWM output to pin 14 on the DB25
and create two parameters to control the base frequency and duty cycle of the PWM to facilitate easy variable power control of Laser modules via Gcode. This is a new software feature (hardware is in place) and when available will work on all Acorn Hardware.
Any update on this release?

I've been able to get my laser working with on/off only using M10px & M11px commands (x is the relay board port number). I turn a fan on/off with the M3 & M5 commands. I modified a post processor to make this all work. see attached (I added the .txt to allow it to upload. You need to remove that so the file extension is .pp - save that post processor file in your vetric postP folder - C:\ProgramData\Vectric\VCarve Pro\V9.5\PostP on my machine. It will then show up as a post-process in the drop-down list.

You also need to add the port assignment for the M10/M11 and M3/M5 to the wizard.
I know this is an old post, but I wanted to suggest something that I was reading about regarding another laser power supply interface controller. That is, the ability to convert the 0-10v (which the Acorn outputs) to a PWM signal. After thinking about it, I realized that this would not be very hard to do using an Arduino. It has a number of ADC and can generate a PWM output at TTL, which is what the typical LED laser power module needs. As the ADC on an Arduino is more like 0-5v (assuming a 5v Arduino), you would want to use a voltage divider, a very basic circuit to create.
martyscncgarage
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Re: J Tech Laser - compatibility question

Post by martyscncgarage »

Analog to PWM Converter:


PWM is available on Acorn hardware. Software hasn't caught up. Might be a little bit.
Reminder, for support please follow this post: viewtopic.php?f=20&t=383
We can't "SEE" what you see...
Mesa, AZ
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