Laser engraving metal

[VDX]

... 8Watts on a spot of 0.1mm diameter arent enough for bare metal - either paint it black and 'etch' the surface while evaporating the paint, or combine three of this diodes to get enough energy density.

The 40 Watt bar-diode sounds like enough power -- but even with a special focussing methode with 19 fibers attached to every of the emitters and bundled to a 0.7mm diameter output (this is the common methode for this type to get them into a fiber) it's not enough power to harm metal - for engraving it's even weaker than the 8Watt-diode, because 40Watts on 0.7mm is much, much lesser energy density than 8Watts on 0.1mm!

Viktor

[ArctosLaser]

We use an 80W CO2 tube to engrave black anodised aluminium. Also cuts pretty thick plexiglass, 10mm or more.
Looking to go to a slightly lower power 1064nm single mode fibre set up in future, better beam quality, but apparently can look at cutting metal at this point.

[dnar]

The Epilog 25W Fibre Marker laser works brilliantly on anodised Ali and also SS. Best result require finding the optimal pulse frequency and scan speed.

The old way of marking SS is to first coat the surface with a nasty carcinogenic paste....

[macpod]

Well it's not engraving metal, but this reminds me of CerMark which I have used on anodized Hammond cases with good results (40w co2). Pretty expensive stuff however

This also made me recall this:
http://hackaday.com/2014/12/25/laser...aster-alcohol/