I have been messing around trying to etch stainless steel but haven’t had much luck. It will look good but won’t really stand up to a real good scrubbing. I think surface prep might have a lot to do with getting a good contrast. I am going to try again and be a little more scientific in how I do my tests.
The dark etchings are just cleaned with alcohol (I find it works better than acetone). The lighter etchings are after I scrub with soap and a scotch bright pad.
What laser are you using and are you coating the stainless with anything?
I just did a recent post on engraving number and letters on stainless. If I can figure out how to link it I will.
Here is what I coated the stainless with.
It was just two days back and there is a picture…
I am using a K40 and the same dry moly you list above
Check this link: https://youtu.be/jP9ncWksEGw
Check this link: https://youtu.be/jP9ncWksEGw
Check this link: https://youtu.be/jP9ncWksEGw
Did you see the link below?
Very interesting this last utube of Sebastin’s is exactly what I’m seeing with engraving under the microscope as. I’ll see if I can post a picture. Martin, the only difference I can see is I’m using a different aftermarket lens a ZnSe- F50.8 mm.
http://www.lightobject.com/Improved-18mm-ZnSe-Focus-lens-F508mm-P206.aspx
Martin and all, here is a microscopic view of the the lettering with CRC used. It’s about 3.8mm tall. After RDworks lab 100’s post It I get time today I’ll try it without the coating.
I’ll also revisit the power settings and feed rate.
I used a product called Minehan Circle Spray (got in Australia, http://www.minehanagencies.com.au/lubricants.html#circlespray). This has a significantly higher % of MoS2 compared to the CRC spray I see a lot using here (something like 90% compared to 8%). I found that almost all of my etchings onto stainless with this stuff came out quite dark (@around 10mA power & 200mm/s). Also, when cleaning up I literally just washed the excess off with water & a sponge & a little elbow grease.
edit: I forgot to mention that the etchings have held up pretty well over time too. Can’t even scrub them off with a scourer/scotch pad. One, on a stainless bowl rim, has been through the dishwasher about 100 times too & is still visible & reasonably dark.
http://www.minehanagencies.com.au/lubricants.html#circlespray