Today I tried my first laser engrave. Up until now I have only been doing profile cutting with my lasercutter. It took me some tries to get it to work (turns out you can’t just import a grayscale image and press start…).  I found this very helpful guide on CNCzone, which led me to much better results.

Here’s the rundown (for Photoshop):

1)        Convert image to 8-bit greyscale   (image – mode – greyscale)

2)        Resize the image to the size it’s going to get engraved, using 300ppi.   (image – image size)

3)        Bump up both contrast and brightness about +25. You don’t want the photo to be all areas of medium grey.   (image – adjustments – brightness/contrast)

4)        Here’s the VITAL part: use an unsharp mask filter at 500%, radius 4px and threshold 0.  This will exaggerate edges radically, but that’s what you need. In fact you can do this and then still add another unsharp mask after this one at 150% , 1px radius and 0 threshold if you want even more edge detection.   (filter – sharpen – unsharp mask)

5)        Convert the image to a bitmap using 150ppi and a diffusion dither.   (image – mode – bitmap)

6)        Laser. Power at a very low setting, speed at max.

Don’t mind the picture, it was a booze-laden night :-). It turned out okay, although the contrast between the engraved and virgin areas is not as high as i’d hoped.

Then, I decided to turn it into a puzzle, because, well… just because I can…

Some oft the pieces fell down and got all screwed up. My pin bed is looking less and less useful for small pieces like this. Also, the picture became even less visible with the added cuts. Oh well, lesson learned, it doesn’t have to go according to plan all the time…