Page 13 of 16 FirstFirst ... 3910111213141516 LastLast
Results 121 to 130 of 153

Thread: CNC Laser Engraving 8bit Shades of Grey 445nm

  1. #121
    Join Date
    Jun 2013
    Location
    Florida
    Posts
    82

    Default

    We just finished a new build on our Shapeoko 2 using a 6W 450nm laser Laser Diode from DTR. We are using the Flexmod P3 driver set at 4a max. We were able to reduce the 3D engraving time almost in half compared to using the 2.8W 445nm LD. We are still refining the settings in PicEngrave Pro 5, but here are the results of a 3D engraving that just finished. It's 7.875" X 5.25" in size with a.125" total depth of cut. We used the J-Tech grbl with S20-S255 laser power commands, a variable feedrate (Feed Rate Change) and streamed the 507,365 lines of gcode with our PicSender program.
    Attached Thumbnails Attached Thumbnails 3D Lions.jpg  

    DSC00621.JPG  

    Extensively Re-worked/Re-designed/Modified Servo K2CNC KG-3925, Mini Diode Laser Engraver and now a Shapeoko 2 Laser Diode Engraver.

    https://www.picengrave.com

  2. #122
    Join Date
    Aug 2015
    Posts
    1

    Default CNC Laser Engraving 8bit Shades of Grey

    Quote Originally Posted by JJWMACHINECO View Post
    Hi everyone,

    I'm new here and I hope this is the right place to post this. I would like to introduce to everyone a new process me and my son developed to laser engrave 8bit shades of grey using a 1W 445nm laser diode on our CNC router. There is no dithering a image first, no pulsing or overlapping dots to get the allusion of shades. What we have developed is a way to vary the laser diodes intensity by analog modulating the laser diode to get 8bit greyscale. The driver we are using is drlava's Flexmod P3. With our setup, we can just use a standard X,Y and Z g-code from any image to g-code rotary engraving type of program for this process. We use Artsoft's Mach3 CNC controller program to run the gcodes. No special laser engraving software or program is required, but we prefer to use PicEngrave Pro 4 Plus Laser which have been written with specific enhancements for this process.

    Using a laser diode compared to a CO2 to do these engraving is a very slow process, but the results are very gratifying/rewarding for us. This is just our hobby so time to produce them is irrelevant. We have successfully engraved on wood, artist canvas and mirrors with stunning results. With our setup, we can also use Constant Wattage and vary the feedrate to get shades of grey, or use TTL to pulse the laser with a dithered black and white image.

    The smallest burn line we are able to achieve is .007" because of the 3 element glass lens we are using now. Does anyone know of a source of any optics with the 9X.5mm thread that can focus down any smaller then what we are getting now? We are looking into improving the detail and sharpness of our engravings that can be achieved.

    Here is an example of our analog modulation engraving process being used on Birch Plywood.

    Jeff
    hi JJWMACHINECO
    please help me:
    how to setting on mach3 to control laser power ????
    what I need anything for do it ????
    thanks
    lam nguyen

  3. #123
    Join Date
    Jun 2013
    Location
    Florida
    Posts
    82

    Default

    Here is a 3D engraving using an Air Assist designed by us with a 6W 450mn Laser Diode from DTR. It's made out of Delrin and is screwed onto the lens thread and seals against the laser module. There is a hose barb in the side for the air to enter and both the laser beam and air exits out of the tip through a 10-32 SS set screw with a .04" orifice.

    I Gaussian blurred the image to smooth out the toolpaths, but I blurred it a little too much and lost some of the detail.
    The gcode was generated with PicEngrave Pro 5 with a variable feedrate on each of the 737,935 lines of X,Y,Z & F gcode and was streamed with PicSender using grbl 9J.

    The Flexmod P3 laser driver's modulation is controlled with a US Digital 10bit MA3 analog magnetic shaft encoder driven by a nema 17 stepper. This setup allows us to switch from the Z axis stepper to adjust the laser's focal height from the material, then switch to the encoder's stepper to control the laser's intensity with Z axis depth commands.

    Attached Thumbnails Attached Thumbnails bear.jpg  

    Extensively Re-worked/Re-designed/Modified Servo K2CNC KG-3925, Mini Diode Laser Engraver and now a Shapeoko 2 Laser Diode Engraver.

    https://www.picengrave.com

  4. #124
    Join Date
    Jun 2013
    Location
    Florida
    Posts
    82

    Default

    Here is the Air Assist we designed for the EmBlaser and it fits within the laser beam guard so no safety features are compromised. It's made out of Delrin and is screwed onto a J-Tech lens's thread and seals against the laser module. There is a hose barb for the air to enter and both the laser beam and air exits out of the tip through a 10-32 SS set screw with a .025" orifice.

    The hose barb was rotated to the side for slipping the laser unit onto the mount. It then can be rotated to the rear and the set screw keeps it in place. The laser guard needed a round groove filed in the rear so the air hose would fit through it when it's attached to the heatsink. We used a Craftsman oilless air compressor with 5PSI regulated air pressure and a toggle switch valve to turn the air on/off to the air assist. The air hose is very flexible PVC. This setup allows us to 3D laser engrave using PicEngrave Pro 5 generated gcode.

    Attached Thumbnails Attached Thumbnails DSC00139S.jpg  

    DSC00140S.jpg  

    DSC00142S.jpg  

    dog.jpg  

    Extensively Re-worked/Re-designed/Modified Servo K2CNC KG-3925, Mini Diode Laser Engraver and now a Shapeoko 2 Laser Diode Engraver.

    https://www.picengrave.com

  5. #125
    Join Date
    Jun 2013
    Location
    Florida
    Posts
    82

    Default

    With these I made the background white in the image and used Skip White in PicEngrave for optimizing the toolpath so it limited the travel area and cut down on the engraving time. First one was done on the Shapeoko and the second on the EmBlaser. The 6W engraved much faster, but the 2.8W on the EmBlaser gave more detail because the size of the focused beam is smaller.
    Attached Thumbnails Attached Thumbnails Shapeoko1.jpg  

    EmBlaser1.jpg  

    Last edited by JJWMACHINECO; 10-16-2015 at 12:23.
    Extensively Re-worked/Re-designed/Modified Servo K2CNC KG-3925, Mini Diode Laser Engraver and now a Shapeoko 2 Laser Diode Engraver.

    https://www.picengrave.com

  6. #126
    Join Date
    Aug 2013
    Location
    Florida
    Posts
    9

    Default

    Holy Moley!

  7. #127
    Join Date
    Oct 2015
    Posts
    1

    Default

    Hi Jeff, really impressive your work. I was wondering which software you used to convert the picture onto height map. Cheers.

  8. #128
    Join Date
    Jun 2013
    Location
    Florida
    Posts
    82

    Default

    Thanks,

    I downloaded the Depth Map from here:

    http://hobbycncart.com/load/ingyenes...eto_reliefek/3
    Last edited by JJWMACHINECO; 10-21-2015 at 07:56.
    Extensively Re-worked/Re-designed/Modified Servo K2CNC KG-3925, Mini Diode Laser Engraver and now a Shapeoko 2 Laser Diode Engraver.

    https://www.picengrave.com

  9. #129
    Join Date
    Nov 2015
    Posts
    3

    Default

    Hi,
    I'm planning to buy a NUBM44 of 6W with a G-2 lens here : https://sites.google.com/site/dtrlpf...nm-laser-diode
    But I got one question, which will be the spot size at 7/8 cm from the laser. Will it be under 3mm ?
    Thanks

  10. #130
    Join Date
    Oct 2012
    Location
    Germany
    Posts
    1,478

    Default

    ... the 'spot' in 70mm distance would be more a line with roughly 6:1 aspect ratio, than a round shape :/

    Viktor

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •