Where is the laser engraving category?

What version of grbl are you using with our PicEngrave Pro software?

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I am using GRBL 0.9j and I know that JTech has said there might be issues with photo engraving but I think the issue is more the photos I have tried to engrave. One was an old B&W photo that turned out really dark. I am open to any suggestions you might have.

With the laser, wood type matters as far as darkness and speed of the laser moving across it. The Picengrave have been a very good source of info so I don’t want to take away any recommendations they have. I noticed cherry, pine, and plywood take the laser pretty quickly so darken up faster. I would increase your speed for the laser/CNC machine movement to reduce the darkness. It is challenging and perhaps time consuming but a quick practice run on the same wood you are using does help.

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First, the standard GRBL 9j is not set with the proper PWM frequency for the J-Tech driver. It will require a higher S command value & PWM voltage before the laser will even come on. With this scenario, you are loosing the lower modulation & shade range, so your over all engraving will be darker.

Second, the GRBL 9j does not execute the S commands in real time. It has a slight dwell on every line of gcode. You can overcome some of this dwelling by increasing the accels for the X&Y, but it will still dwell and effect the outcome. By not being able to get up into the higher feedrate range because of the dwelling, it will cause your overall engraving to be darker too.

Vector cutting & engraving with Black & White images where there is only two laser power S command values or just M03/M05 for on/off in the file will work fine, but when there is varied S value commands on every line of gcode, it will not give you very good results no matter how good your original image is.

Have you tried the J-Tech LaserMode PWM GRBL yet? Some have reported it does not work with the X-Carve’s UNO, but I purchased one from inventables and I have not had any problems with it. It works flawlessly with the J-Tech GRBL. I used it with the last engraving I posted in this thread.

I know it is not desirable to switch back and forth to different versions of grbl, but with our PicSender & the XLoader it’s quick and easy. I got it down to 1 minute 15 seconds and that is even changing the grbl settings for the one I will be using at that time.

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So the X-Carve functioned fine with the J-Tech GRBL? What spindle where you using? I may have to try this out and see what kind of results I have.

I don’t have a spindle on our Shapeoko, only a laser, but I do test different versions of grbl back and forth quite extensively with PicSender.

You can switch to the grbl 9j for your spindle or vector laser gcode files, then switch to the J-Tech PWM grbl for raster laser engraving.

After connecting to the com port in PicSender, select the yellow GRBL button, then Display Settings, then Save. Name the file something like X-Carve GRBL 9j. Return to the main screen, select Close, not Exit. Open the X-Loader and flash the newer J-Tech PWM GRBL 9g with Homing enabled to the UNO. You do not need to close the X-Loader. Open the Com port again in PicSender, go to the GRBL menu and select Display Settings. Change these settings in the left message window.

$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=4500.000 (x max rate, mm/min)
$111=4500.000 (y max rate, mm/min)
$120=8000.000 (x accel, mm/sec^2)
$121=8000.000 (y accel, mm/sec^2)

I have both of the X&Y Accels set to 12000 on my Shapeoko 2, but it has nema 17 steppers and no added spindle weight to move. You may have to adjust the settings slightly for your X-Carve, but this will give you a starting place.

After changing these values, select Send, then Save again. Name it something like J-Tech PWM GRBL 9g. Return to the main menu, Home your machine and set your work X,Y & Z (Z for focal height) Zeros with GRBL Z Code selected, then change to the GRBL PWM Code to run your X,Y & S command raster Laser engraving file.

To switch back to GRBL 9j, Close the Com port in PicSender, flash the GRBL 9j with X-Loader, Open Com port in PicSender, go back to the GRBL menu, select Open, load the X-Carve GRBL settings, then select Send. Return to the main menu, select GRBL Z Code and your ready to Home your machine and set your work zeros again.

I know it may sound complicated now, but after doing it a couple of times, it will get easier and quicker.

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Easy GRBL settings saving and loading is another great reason to use PicSender!
Use it when fine tuning.

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i have a problem with pic sender,in the middle of working ,the program stop sen any data.

You need to disable the USB Power Management and prevent your PC from going to sleep.

Depending on what version of Windows your running, these videos may me different on how to make these changes to your PC.

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Put together another whiskey box. Lasered the front with the text with the picengrave pro and picsender software with the jtech 2.8w laser.



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Followed up with a quick USN Carrier coin holder made from cedar. Text was developed in power point, saved as a jpg, and then used picengrave pro 5 and picsender with the jtech 2.8w laser. I used an 8mm bit to cut the grooves and circles using the v-carve pro software. Thankfully my wife helps with the polyurethane coats.



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Our new PicSender v2.3.0 is now available for download.

http://www.picengrave.com/PicSender.htm

Added Features:

• Pause/Resume for Spindle & Laser. PWM off/on control.
• Change Feed Rate During Gcode Streaming.
• Gcode Editor.
• Tool Position Setting Menu.
• 45 Degree X&Y Jog Buttons Added.
• Increased Streaming Performance.

Just finished this engraving with our 6W LD on Birch Ply. The feedrate was set at 180IPM with a 25% FRC. The size is 11" X 8.1" and it took a total time of 2:00:44 to stream the 1,826,605 lines of X,Y,S & F gcode commands to laser engrave the image. The J-Tech PWM grbl 9g firmware was used.

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I wanted to try laser engraving the same image on the back of a mirror with our 6W laser this time. I added a frame to the border so the engraving would blend into the mirrors reflection on the edges. Laser engraving on mirrors gives similar results as spindle engraving Lithophanes, except the image is visible when backlit or not.

I Dithered the image to 1bit Black & White in the PEP5 image editor so the laser would just pulse on/off. I then Flipped the image so it will view on the front properly. I used the Negative selection so the white areas will burn with the highest power which comes out white on the front. The mirror’s reflection gives you the black shading effect.

I set the feedrate at 150IPM with a FRC of 20%. Black areas ran at 150IPM at zero laser power (off), then it slows to 120IPM to burn the white areas at full laser power. There are 1,642,528 lines of gcode in the file and the size is 10" X 8". It took 2:07:02 in time to engrave. The hardest part is trying to take pictures of the finished mirror engraving because everything in front of it comes out in the photo.

Here it is backlit.

Here it is without being backlit.

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We found this inkscape extension to generate puzzle vector patterns, so I decided to give a try.

http://tuts.ahninniah.graphics/how-to-make-a-jigsaw-puzzle-with-gimp-and-inkscape/

We created a 10" X 10" puzzle in inkscape and saved it to a DXF format. We then imported the file into KeyCreator to generate the gcode for cutting it with our 6W laser diode.

We first TTL laser engraved (pulsed on/off) a B&W image on 1/8" Birch Ply the same size as the puzzle pattern we created, then cut through the Birch Ply afterwards.

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Same engraved image, but I cut 144 puzzle pieces this time.

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We just did a feedrate test engraving a Dithered image with just S0 (white) S255 (Black) commands to pulse the laser on/off. The Feedrate was set at 200IPM in the gcode file and it took 47:29 (2849 sec) in time to engrave. The engraving is 10" X 8.34", but we used Skip White in PicEngrave Pro 5 to cut down on the overall engraving time.

We reversed engineered the gcode and it has a 9417.644408 inch perimeter (travel distance). To confirm the actual feedrate it engraved at, we did a simple calculation.

9417.644408 / 2849 = 3.305596492804493 * 60 = 198.3357895682696 Inches Per Minute.

This test confirms that the S commands for laser control are executed close enough in real time when using the J-Tech PWM grbl. To achieve these kind of accurate feedrates, some settings need to be changed in grbl to increase the overall performance.

$0=30 (step pulse, usec)
$1=255 (step idle delay, msec)
$10=18 (status report mask:00010010)
$11=0.005 (junction deviation, mm)
$14=1 (auto start, bool)
$110=5250.000 (x max rate, mm/min)
$111=5250.000 (y max rate, mm/min)
$120=12000.000 (x accel, mm/sec^2)
$121=12000.000 (y accel, mm/sec^2)

Here is the laser’s travel path. There was a total of 587639 lines of gcode that we ran with our PicSender streamer…

Here is the TTL engraving on Birch Ply.

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200IPM, 30% Feed Rate Change, .007" Pixel Resolution, Min 20/Max 255 (full) laser power, 10"X10" engraved size and 2,053,505 lines of gcode streamed with PicSender. 2:14:00 total time to engrave on Birch Ply with our 6W LD.

Original image that was resized, edited and cropped in PEP5.

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We have been testing the new PicConvert DAC from J-Tech Photonics and our results have been very successful. The DAC takes the Z,A,B or C axis step & direction signals and outputs Analog Modulation or PWM to a Laser driver for engraving photos. For those that use Mach3 or TinyG CNC controllers with there X-Carve that want Varied Intensity laser control for 2D or 3D Laser engraving, this will give you that option.

We did this one with Mach3 using an Analog Modulated M140 2W Laser Diode on Birch Ply with the new PicConvert DAC.

https://jtechphotonics.com/?product=dacpwm-converter-board

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Just finished a laser photo engraving on our EmBlaser using one of these RCA Cambio 2-1 Tablets.

With PicSender and this Tablet, it streamed 1,881,908 lines of gcode flawlessly. This was done on 8"X10" .08" Grey Chipboard.

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