CNC Laser (my project)

[ml038018]

Hi,
I'm new to projects with a laser. I have 2W TTL laser mounted on my Arduino GRBL.


Picture my CNC

[Picengravertoo]

Nice job! I like that your using linear rods instead of plastic wheels. Did you make your own driver board also? I have not seen one like that before and noticed your name on it.

[ml038018]

Thank you.
Yes, I made my driver board.
The machine is currently in the testing, TTL Laser working problem with engrave. I want to use GRBL PWM, I need to run the Analog Driver?

[Picengravertoo]

What version of grbl firmware are you using? There is a J-Tech LaserMode grbl 9g hex that can be downloaded on this forums main page. It executes S0-S255 commands in real time and outputs PWM on pin D11 & ground. If your TTL driver can handle a PWM frequency of 1khz. it should work to vary the laser's output power to laser engrave shades.

With the J-Tech grbl these settings need to change.

$0=30 (step pulse, usec)
$1=255 (step idle delay, msec)
$10=18 (status report mask:00010010)
$11=0.005 (junction deviation, mm)
$12=0.002 (arc tolerance, mm)
$14=1 (auto start, bool)
$110=2540.000 (x max rate, mm/min)
$111=2540.000 (y max rate, mm/min)
$120=8000.000 (x accel, mm/sec^2) <----------Play with the X&Y accel settings for your machine.
$121=8000.000 (y accel, mm/sec^2) Our Shapeoko 2 is set at 12000 for the X&Y.

This grbl firmware will not run arc commands or a G0/G00 rapid move. It's setup to just run raster gcode files for laser engraving photos/logos.

Jeff

[ml038018]

Hi, Jeff
Thanks for help. I use firmware Grbl v0.9j, change the J-Tech.
My laser http://www.ebay.com/itm/Focusable-high-power-2W-450nm-blue-laser-module-with-TTL-12V-input-Wood-carving-/331616652602?hash=item4d35e48d3a:g:xScAAOSwxp9W9Uug
Frequency for TTL control : 0-20kHz
I will call you the results.

[ml038018]

The bad news
I am very sad, after settings my laser burned down. Off of my driver board does not work, before that he worked fine, why did it happen?

[Picengravertoo]

With the J-Tech LaserMode grbl the PWM will not turn off completely when jogging. It gives you a threshold beam to line up on your material for zeroing the X&Y axis. If this is a problem for you, place an on/off switch inline from D11 to the TTL modulation input of your laser driver. Jog in place and then switch on to run the gcode to engrave.

[ml038018]

Hi,
My first result of burning. Settings configured as you told.
I changed:
$120=12000
$121=12000

PEP5 Settings

My result

It can advice you to change the settings?

[Picengravertoo]

It looks like your not getting the optimal focal point with your laser. .200mm Pixel Resolution (stepover) is more then it should be? You should be down in the .1524mm Pixel Resolution range. The finer the focal point is, the more burning power/intensity you will have through the shade range. The material your engraving on could be part of your issue also.

You can use the Analog/PWM engraving profile for grbl also. There are more features in there for you to use.

Jeff

[ml038018]

Thank you for help. After two days of the test, arrived my result.
My settings:
Feed - 2200
Pix.Res- 0.14
Left-45°

I wonder could it be better?