Settings for Engraving on Slate

put a light coat of mineral oil on the slate before etching.

1 Like

Pre treat with spray shellac and use full power and speed. I also use spray shellac for engraving on canvas. Its great to have around and it food safe.

18 Likes

I put a light coat of mineral oil on the slate. Typical height of a slate coaster (including rubber foot) is 0.34". I run at: speed 600, power 80%, and 270 lines.

trying to figure out how ā€” is this in a histogram setting? my guess though probably wrong

You pre treat with spray shellac, then engrave ā€” then if you are going to use it for meats & cheeses (IOW food), are you going to spray shellac it again to protect the engraved areas so they donā€™t wear?

1 Like

i use the ā€œlevelsā€ settings in photoshop (ctrl-L)and move the sliders for mid values till they look good

1 Like

After that point, do you save it as a PDF or bring it into Illustrator and save as an SVG? I havenā€™t used Photoshop since I got my Glowforge several years back.

actuallyā€¦ i save it as an uncompressed .jpgā€¦
Glowforge does a nice job of ripping bitmapped files as well like .bmps and .jpgsā€¦

thenā€¦ on slate i use vary intensity to burnā€¦ and on wood i usually use ā€œdotsā€

So Iā€™m confused! I did everything exactly as everyone suggested and somehow ended up with this. Now I know someone is going to say my machine must have been bumped during my second pass but I only did one pass so there is no reason for it to look like this.


Was this done without the honeycomb tray?

The good news is that you can sand the slate and get back to a fresh surface to re-engrave once you figure out your issue with the GF or design.

3 Likes

I think itā€™s in the file. The image was inadvertently doubled somehow. Or maybe it was doubled in the GF GUI.

1 Like

8 Likes

It was one of my wheels were cracked, all fixed and going for it again right now

3 Likes

Hi I was wondering how you got it to shadow the slate

not sure the exact meaning of your question - but happy to helpā€¦ the slate itself is ā€œblackā€ (dark)
the images glowforge burns into them make the slate go ā€œwhiteā€ (actually just a light shade of grey)
soā€¦ i take my image in photoshop and invert it (make it a negative)
verything i want white/light is actually black in the fileā€¦ that shadow or fade from left to right is in the photo itselfā€¦ dramatic lighting makes for those darker shadows (and painting on top of them in photoshop)

is that what youā€™re asking?

1 Like

Yes that is. Thank you so much. And sorry, I didnā€™t realize I had a message. Thank you so much for your help

I see google says coconut oil could be a replacement for mineral oil. Do you think it would work in this application?

Iā€™d probably go with mineral oil just because it wonā€™t go rancid over time like a vegetable-based oil will.

You can get mineral oil at any pharmacy, itā€™s extremely inexpensive.

3 Likes

Cool Thanks.