Laser head on ormerod

Hi all.

I want to put a laser head on my Ormerod, in order to print buttons for my home automation system using this technique:
[youtu.be]

I have ordered this laser head with driver:
[www.aliexpress.com]

It has a TTL input for modulation, which I want to hool up to a PWM output on the Duet controller (mine is 0.6), in order to control the intensity of the laser (in the video above he uses a 300mW laser, but maximum duty cycle is approximately 3.5%).

Does anyone have suggestions regarding the best way to achieve this? Should I use the cooling fan output (as I assume that is controllable from G-code)?

@dc42: What is the PWM frequency and resolution of the fan output (using your firmware)?

Best regards,

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Mikkel Holm Olsen
AKA Spaceman Spiff

The PWM frequency is configurable from about 10Hz to 65535kHz. Resolution varies depending on frequency, normally better than 8 bits, never higher than 16 bits,

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thanks,

Is there any additional documentation regarding using a laser, apart from the M452 doc:
[duet3d.dozuki.com] ?

From the example it seems using a heater output to control the laser is better. But how to configure the output?

Edit: Is the M452 even supported on Duet 0.6? The docs mention something about FW 2.02, but the firmware I recently installed is 1.22 (2018-07-26b2).

Best regards,

Edited 1 time(s). Last edit at 01/22/2019 03:21AM by spiff.

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Mikkel Holm Olsen
AKA Spaceman Spiff

https://reprap.org/wiki/G-code#M452:_Select_Laser_Printer_Mode

Quote
reprap.org/wiki
RepRapFirmware
1.20 and later

Thanks

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Mikkel Holm Olsen
AKA Spaceman Spiff

I finally had some time to get on with attaching the laser to my ormerod. I disconnected the heating cartridge on the hotend and initially just tried to light the LED on the hotend board.

This is the G-code I start off with to switch to laser mode:

M563 P0 D-1 H-1
M563 P0 D0
M307 H1 A-1 C-1 D-1
M452 P1 R255 F200 I1

However, I couldn't make the homing commands work (I had changed the S-parameters to H-parameters per the instructions).

Then I found out that the 1.22 firmware I was running did not work (although it did say "switched to laser mode"). After upgrading to 1.23 the homing commands with H-parameters work.

I strapped the laser on the print head. Connected the laser modulation input to the hotend heater connector (using a diode).

It seems that with the correct G-code I am now able to turn on and off the laser. If I issue M3 S255 laser is on (max power), and M5 turns it off.

The issue is that I am trying to use laserGRBL to generate the G-code, and when doing raster it seems to generate G-code where there is a G1 command which spans several lines, each with a new X-coordinate and an S-parameter (laser power level). Is this G-code format invalid (e.g. should there be a G1 command on each line)?

Even when fixing this in the G-code, it appears that laser is turned on and off with M3/M5 only. It seems that the S-parameters on G1 do not change the laser power at all. My understanding was that the laser was supposed to be on for G1 moves and off for G0 moves (and that the power level could be set in the G1 moves as well). Is there something I am missing regarding the laser mode?

Or is there some other software that is better suited to generate the G-code for this laser mode?

Best regards,

---

Mikkel Holm Olsen
AKA Spaceman Spiff

That style of GCode (repeated coordinates without repeating the G1 command) is supported in CNC mode. I can't remember whether it is supported in laser mode.

I think the standard RRF binaries for Duet 06/085 are compiled with full laser support disabled to reduce RAM usage.

Edited 1 time(s). Last edit at 05/18/2019 09:15AM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thanks for your reply @dc42,

Regarding the G-code style, the web interface reported a lot of G-code errors, but whether that is because it is not supported in laser mode, or just because my firmware is not compiled with full laser mode, I do not know.

But if I get a firmware compiled with full laser support, should the G1 commands enable the laser and G0 disable it?

And should setting the power level with S-parameter in the G1 command be supported?

Thanks in advance,

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Mikkel Holm Olsen
AKA Spaceman Spiff

Yes, by "full laser support" I meant with support for the S parameter in G1 commands to control laser power.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thanks @dc42,

I found the following

#define SUPPORT_LASER	1	// set nonzero to support laser cutters

... in RepRapFirmware/src/Duet/Pins_Duet.h, but I see that was only added 12 days ago.

Does that mean that 1.24RC5 would be worth trying? I guess that would be much easier than trying to build the firmware myself

I guess I will try it out and report back here how it goes.

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Mikkel Holm Olsen
AKA Spaceman Spiff

Yes, in response to your posts I enabled full laser support in the Duet 06/085 build of RepRapFirmware. So it's worth trying. Caution, I no longer run tests on the Duet 06/085 build unless I am alerted to particular problems with it.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thanks.

I will try it out as soon as I get the chance, and let you know how it went

---

Mikkel Holm Olsen
AKA Spaceman Spiff

Quote
dc42
Caution, I no longer run tests on the Duet 06/085 build unless I am alerted to particular problems with it.

Is there an updated ETA or price estimate on the Duet 3? Still Q3?

Edited 1 time(s). Last edit at 06/11/2019 06:38AM by aniron.

Quote
aniron

Quote
dc42
Caution, I no longer run tests on the Duet 06/085 build unless I am alerted to particular problems with it.

Is there an updated ETA or price estimate on the Duet 3? Still Q3?

Yes, still Q3. But is there a reason you need Duet 3, not Duet 2?

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42

Quote
aniron

Quote
dc42
Caution, I no longer run tests on the Duet 06/085 build unless I am alerted to particular problems with it.

Is there an updated ETA or price estimate on the Duet 3? Still Q3?

Yes, still Q3. But is there a reason you need Duet 3, not Duet 2?

I'm not in any particular hurry to upgrade from my Duet 06/Duet shield.
But when I'm forced to, might as well get the six stepper drivers I need on the base board, possibly the Duet 3 will also be cheaper than Duet 2 + Duex?

Finally I had a little time to spend on this project...

Installed FW 1.24 and did some experiments, but unfortunately I still cannot make it work the way I want.

I have the following in lasermode.g:

; LASER SETTINGS
M563 P0 D-1 H-1 ; clear tool
M563 P0 D0 ; create a tool - no heaters
M307 H1 A-1 C-1 D-1 ; Clear Heater 1
M452 P1 R255 F200 I1 ; switch to laser mode using Heater 1 PWM to control the laser

After homing and then executing this file, I can turn on the laser (low power) with M3 S10 and off with M3 S0 or M5.

However, trying to do any move (G1 or G0) turns off the laser, regardless of whether there is an S-parameter in the move command or not.

Does anyone have experience with laser mode on Duet/RepRapFirmware? Any suggestions for a working G-code snippet? Or does this seem to be a firmware problem or configuration?

Any suggestions are appreciated.

Best regards,
Mikkel

---

Mikkel Holm Olsen
AKA Spaceman Spiff

Quote
dc42

Quote
aniron

Quote
dc42
Caution, I no longer run tests on the Duet 06/085 build unless I am alerted to particular problems with it.

Is there an updated ETA or price estimate on the Duet 3? Still Q3?

Yes, still Q3. But is there a reason you need Duet 3, not Duet 2?

Hmm, it is possible to do dual independent z-steppers on Duet 06/Duet shield with your firmware, right?

Quote
aniron
Hmm, it is possible to do dual independent z-steppers on Duet 06/Duet shield with your firmware, right?

In theory yes, but AFAIK it hasn't been tested.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thanks, I guess I get to test it then.

@OP, sorry for the thread hijack.

Hi! I need help with my setup. I own a Duet 0.6 as spiff. It's been working as a 3D printer controller for some time. Now I've a laser module to plug in my machine. Following the instructions given on this thread I was able to power a LED on M3 commands by using a voltage divider on the H1 (main extruder heater), as it's rated 12v.

I would like to use heater 3 for this new tool or any other heater not being used.

So, could you help me finding the corresponding pin on the expansion header? I've searched over the reprappro website, the github repo.. no success

Bear in mind, my board is an original Duet 0.6. This schematic [https://github.com/T3P3/Duet/blob/master/Duet_Expansion/Duex5v0.7/Duex5_Schematic_V0.7.pdf] points to pin8 on the expansion header, labeled as HEATER3. I tried with the commands (adapted from spiff's):

; LASER SETTINGS
M563 P3 D-1 H-1
M563 P3 D0
M307 H3 A-1 C-1 D-1
M452 P3 R255 F200 I1

No success. I've a LED and multimeter connected to this pin and GND, no change, always 1.63V. Shows 3.3V on 5V rail
Is it the correct pin on the expansion header?
Wrong commands?
Thanks for your help

Wrong pin. The DueX5 is not compatible with the Duet 0.6. The compatible expansion board is the DueX4.

Heaters 2 3 4 5 on the Duet 0.6 are processor pins PC6 PC23 PC22 PC21. These are expansion connector pins 18 21 22 23.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Great!
I had to edit my homedelta.g file, changing S2 parameters for H2
Now it goes perfectly!

Thank you so much

Edited 1 time(s). Last edit at 04/02/2020 11:51AM by gonalonso.