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View Full Version : Laser Engravers ( Educate me)



spluppit
21-01-2017, 06:03 PM
I have a colleague who is looking at a laser engraving machine for commercial use for engraving their own products. Most of this engraving will be in stainless or powdered surfaces then the engraved area filled. I think the latter is fairly standard process for powdered surfaces, as far as i know anyway.

I may well be involved with this machine and its running hence why i am asking the questions.

I have zero education with laser engravers, brands, different systems, methods, laser powers etc and so forth. As such I'm looking for advice and a run down on the above points. I know from memory there have been guys on here using laser engravers for what appeared more commercial uses. So advice on good reliable and durable brands from people that know is also very welcome so I'm at least looking in the right direction.


just thinking out loud here, is there such a thing as a laser engraver than can cut thin materials and engrave?


Many thanks in advance.

Robin Hewitt
21-01-2017, 10:38 PM
50W carbon dioxide laser tubes are reasonably compact, only about 3 feet long. The thing they cut best is acrylic because that vapourises. You can cut paper, cloth and thin wood. If your material gives off lots of stinky smoke, the glue in plywood is particularly bad, you need to force air down the beam to disperse it.

80W tubes are a lot bigger, if 100W tubes are not getting silly size wise then 120W tubes most certainly are. Check them out on e-bay, see what they reckon the various tubes will cut/mark. Lasers are fun with acrylic but can be disappointing with other materials if you want instant gratification.

With 120W you might just be getting to the point where it would cut wafer thin metal, a solder paste mark perhaps, but a minimum of 1000W, probably with oxygen assist, is what you see in laser metal cutting movies.

At low power, everything metallic the beam hits has to scatter the light, if it reflects then it will not so much as mark the surface and it would be extremely dangerous. Even the 50W tube unfocused will blind you faster than you can blink. There are coatings you can apply to help mark metal surfaces but it is marking, not engraving, there is no real cut unless you have the power.

Have fun, stay safe.

alboy
22-01-2017, 12:14 AM
You can etch on to metal surfaces with a CO2 laser but for many metals you would have to treat them with a coating for the laser to be able to etch because of the reflective surfaces. You certainly will not be able to cut metal with a CO2 laser found in most of the smaller machines but the larger ones use what I believe is callled fusion CO2 where oxygen is used while cutting, very expensive if you want to cut sheet metals then a fiber laser, pulsed Nd:YAG, laser will be required, also very expensive. These types of lasers will generally etch metals without needing a special coating as well.
I can't really comment much on the metal cutting lasers as I only use my 100w laser for etching metal, wood and glass and cutting ply and acrylic.
Trotec lasers have a good reputation but I have no experience of them.

spluppit
24-01-2017, 12:27 AM
Many Thanks gents. I had a phone about today and had a few explanations from commercial suppliers in an effort to educate myself further....Not sure if i actually succeeded. All i think i know is you can spend up to 60k! Errr you can get a darm nice machining centre for that!