CNC Laser Engraving 8bit Shades of Grey 445nm

[JJWMACHINECO]

Laser engraved on Brown/Gray Chipboard with our 3W EmBlaser.



This one was done on Brown Chipboard.



Original image.

https://upload.wikimedia.org/wikiped...otive_shay.jpg

[jdmejiab]

Hi Everyone, May I ask for some help? I buy this unit http://www.gearbest.com/3d-printers-...pp_343187.html but the laser module is dead, so I want to upgrate it.
any one have an experince with this unit or similar?
I buy a 1.8W 445nm A-Type M140 Blue Diode with 1.8A X-Drive V6 Laser Driver - M140, is ok if I connect that laser and driver to that NEJE machine?
thanks a lot for all you help and comments.

[JJWMACHINECO]

This was done with Mach3 & J-Tech's PicConvert DAC for modulating a M140 2W 445nm laser diode on Poplar. The PicEngrave Pro 5 settings were A.000 Min & A-.0255 Max, 70IPM, 25% Feed Rate Change and .006 Pixel Resolution at a 45D angle using the Ellipse feature.

https://jtechphotonics.com/?product=...onverter-board

The size is 4.75" X 5.75" with 600,229 lines of gcode and it took 1:36:46 in time to engrave.

[Picengraver]

Very nicely done, Jeff. May he rest in peace.
John

[TobyTetzi123]

Hello,
I am Toby from Germany.
I've mount a DTR Laser on my CNC Mill that used Mach3.
I used Spindle PWM for power the TTL input of the SXD Driver.
The regulation of Laser power does well.

But does anyone know, everytime I start a line I had a delay?
My G code use only M03 at start and M05 at the end, otherwiese I only use S Codes.
I thougt only M03 and M05 Codes have a delay?

Here you can see it very good.


Regards Toby

[VDX]

... I had something similar with a comercial CNC-software (normally used for milling) -- the moving commands were calculated and queued in a lookahead buffer, but switching of the I/O-pins was 0,3s delayed ... so different to your case, where the pin switches, and the start move is delayed.

In the end the developer changed it for exact syncing, so from then on the software was usable for laser-engraving too

Viktor

[TobyTetzi123]

Hello,

I need some time, but now I got sucssess.

I build a Step/Dir to PWM Converter and use it with the A Axis to change the Laser Power.

I had made some changes to Image2GCode Software to be Mach3 friendly.

Here are the result.




And here is my work of today.





Regards Toby

[JJWMACHINECO]

It does not look like you are varying the laser diode's intensity to laser engrave any shades. The same results you are demonstrating can be accomplished in Mach3 by using an axis (Z,A,B or C?) direction pin wired to a TTL driver for pulsing the laser on/off with the gcode generated from a 1bit B&W Dithered image. This gives the allusion of shades which is what your car engraving looks like and your video clearly shows the laser just pulsing on/off.

The CW SquiggleDraw is an interesting concept, but the end results are not really that eye appealing IMO. Your better off to vary the feedrate with CW to engrave true shades. You have been testing our PicLaser software Demo, so give variable feedrate a try.

[GARCAD]

Hi
I've been developing a scheme for true halftone image lasering that's nearly finished.
Here I submit an example for criticism and evaluation:


The material is clear white pine (notice the pitch pockets).
The image size is @ X2.3 Y3.3 inches. The beads in the oval are @ 1mm diam.
Laser dot 'effective diameter' is @ 0.0025 inches and the grid spacing is 0.002625 inches.
The laser is controlled by the step signal of the A axis and is run from gcode that way

There were approximately 1.3 million individual dots in the image.

If anybody wants to try the same image:


The rendering is 16 shades as can be verified by reducing the color depth of the image until it makes a difference that matters.
I've done this with the best foto.laser renderings i can find and none of them exceeds 16 shades so far.
Does anybody have an example that shows greater color depth?
The halftone scheme I'm using can achieve arbitrary color depth at the expense of increasing the image size.

N.B. I am not selling anything. This is not a commercial gambit. If I release the software (when I'm satisfied with it) it will be made available gratis.

[JJWMACHINECO]

Enhanced Grayscale laser photo engraving (no dots) on Poplar done with a 10bit Analog Modulated 2W M140 445nm LD from DTR. The LD driver is a Flexmod P3.

The image editing and the Mach3 gcode generation was done in PicEngrave Pro 6.



For a comparison, this one was done with 8bit Analog Modulation using the same laser engraver and on the backside of the same piece of Poplar.



Here is the original image I started with before any editing.