Hello,
I’m trying to engrave 80W CO2 laser with OMTECH powder (Polvo de Marcado Láser en Metal para Grabadoras Láser CO2 – OMTech ES) into chrome metal. However, it is not working. After firing, part of the engraving is always erased and does not hold. I tried engraving with a speed of 250 mm/s and a force of 70%. I wanted to ask if you have a tip on how to do this? It might be a problem, but I still believe it can be done somehow. I have no problem with engraving in steel.
I’ve tried with stainless steel on my 40W, got poor results and cost me a lens - reflection off the stainless … might want to check yours… I’d think chrome would be more reflective, but I don’t know.
Generally co2 are for natural materials, although all lasers seem to work to some extent as the material changes. Acrylic is far from natural, but works well with co2.
I use LBT100 and lase that… it will molecularly bond to the metal and leave a black mark… This is a stainless steel mug using LBT100 spray.
I would like to see what you’ve done with steel…
My only suggestion is to use something like a laser binding spray or coating and lase that.
I have a 60W fiber for metals…
Hi.
Wow, that’s a logo You most definitely don’t want to mess up.
Any convex or concave surface is always a major PITA to laser no matter what the material/metal, You absolutely need something to keep the focus distance constant.
Won’t be an easy, nor cheap task with any fixed lens system laser.
I’d assume concave would be a breeze with a galvo and an appropriate compensation, convex might not work at all.
Someone with experience about a galvo on irregular surface will probably chime in in no time.
Some ideas that could be adapted to tasks like this when using Co2- or diode lasers were thrown around a while back when a person wanted to engrave on wine barrels, I do not know what his solution was in the end.
The two -or three if the chroming is done properly- thin layers of somewhat dissimilar metals+ the aluminium (?) base doesn’t help things either, as can be seen on the top of the dome where the focus was probably the most accurate.
Expect to ruin a bunch of (timing?) covers when honing out the kinks in any case.
Regards,
Sam
Tradeoffs will get around this to some extent… These are computed depth of field (focus) associated with the lens length and resultant spot size.
| Lens Length | DOF | Spot Size |
|---|---|---|
| inches | mm | microns |
| 2" | 1.90 | 171 |
| 4" | 7.6 | 343 |
Pick the right lens and the focus distance shouldn’t be an issue, within limits…
A fiber isn’t any different, as they use an F (flat) type lens, but that lens also has a dof relative to it’s length.