E.T. go home and have a nice cup of tea



I was inspired by Jule’s post on multi-tone slate drawing. My attempts took way too much effort to get the balance right, but I got there in the end.

One colour looks great and is easy to do (following Jule).

Then I decided to try for a full tone range plus un-burned regions for contrast. These round slates are around $1 each from Amazon, so I could afford to experiment, which was lucky - it took me around 4 coasters before I got the image and the GF settings right.

The shape and texture of the raw material lends itself to spooky or space themes. Here’s a movie I love…

The media was prepared from publicly available posters as well as high quality moon pictures from NASA. I put them together in Affinity Photo for Mac, my final version had like 25 layers (most of which I could probably remove now). The bike and the tree silhouette is 100% white - meaning the laser doesn’t touch that part at all. I didn’t reproduce the full range of contrast in the end - the big crater at the bottom (nearly full black) doesn’t really appear. I think it still works.

Lessons I learned

The Material

  • slate is slightly shiny, the engraving isn’t visible from all angles.
  • the engraving seems quite durable
  • getting it wet or greasy can decrease contrast temporarily
  • there are little shiny specks which make it extra awesome.

Media Preparation

  • alpha in images can cause unexpected noise in the output that you can’t see in previews. I recommend to remove alpha blending to make sure you can see what will be rendered.

Burn considerations

  • full white parts of the image (no burn) must not contain compression artefacts or noise - this will ruin the super contrast you get between burned and non burned part of the image. Avoid jpg (and alpha).
  • it’s a good idea to burn a gradient at different powers on a scrap of the same material (e.g. the back of the coaster). This will help you calibrate.


p.s. The shards are from a penrose puzzle I made one time. I’ll write about that one time.


The ET over the moon is an exceptional result!


Love E.T.!


Wow, amazing engraving! Thanks for all the insights.


Really wonderful!


Loved the ET as well! Well done! Just finishing a Cheese Board engrave in a Slate as well.


Remember there are two sides to each slate coaster when experimenting with settings. :slightly_smiling_face:

Also if you wipe it with mineral oil & let dry you get more contrast.

Finally, if you’re hardcore in reusing them, use some 220 or 320 grit sandpaper to get back to a uniform surface, re-mineral oil and re-engrave.


Stupid question – would that wipe down be BEFORE or AFTER engraving?


Inside the sausage factory:


Problems with noise:


Those are great! (That was one of my favorite movies!) :grinning:


Before. Otherwise you’ll find your engrave disappears :slightly_smiling_face:


Awesome results! I had been working on some slate coasters I found at a craft store. It came out great except that there was a lip in the stone I didnt see. I suppose sanding it down before printing could have prevented it. Still pretty awesome. Do you remember what settings you ended up using?