35mm Brass coin 3D slice Viking head

Done with my 60w JPT mopa using a 110mm lens. 1600 mm/sec, 95%power, 25khz freq., 150 Q pulse, 508 dpi, 425 layers. Took 38 minutes to engrave.


Looks great… mine seem to take quite a bit longer…

Any reason you did 425 layer?


I often do 550 layers for more depth but decided to use 425 to speed the process up a bit. I have the coin in a tumbler right now with sand and steel shot to see how that will work on the finish.

Might want to read this post by Oz on how 3dslice operates…

This link is only for galvo beta tester group… I copied the pertinent information to thread #6


Have you used other abrasives in your tumbler? I’ve got one, vibrating and very noisy, but haven’t found a good abrasive… How does steel shot work?


The page/post you linked to won’t open for me.
I haven’t tried any other tumbler mediums yet. I had a bag of playbox sand on hand and a pack of .25" steel slingshot balls so I’ve been using a mix of those with pretty good results. The tumbler was given to me by a retired jeweller. It’s pretty quiet perhaps because of the sand in it.
I just redid the same image on the reverse side of that coin but increased the diameter from 29mm to 30mm and did 450 passes instead of 425. Total time increased to 40.5 minutes. It’s in the tumbler now. I’ll let it run for 3-4 hours and see how it looks then post another pic of it.

Probably not in the beta galvo group… I’ll copy the pertinent information over here for you…

Oz stated how the 3d operation works and also how it handles other than 256 passes.

With 3D Slice, each pass is thresholded to the current threshold value, and the result is run as a 1-bit image. If you use 256 passes you get exactly one pass per gray-level in the image. Every pixel at or below brightness 255 for the first pass, every pixel at or below 254, then 253, and so on.

If you choose 128 passes, you get every pixel at or below 254 for the first pass, then 252, then …

It “clusters” the layers together into batches if you use fewer than 256 passes, and will duplicate some layers (with even spacing) if you use more than 256. 384 passes would duplicate every 2nd layer. 512 passes would duplicate every layer.

Someone might let you into the beta group if you’re interested… like @JohnJohn may be empowered enough…


Interesting, I was thinking more than the 256 layers was sort of further subdividing things. It was looking to me like I was getting more details showing up by using than 256 layers. I’ve seen some posts on some groups where people have used 700 or more layers which seemed excessive to me.
I might be interested in the beta group to learn more about it all. I’m a retired signmaker who bought my first fiber laser as a retirement gift to myself to keep my hand in making things.