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View Full Version : New to lasers need some advice - Fiber vs CO2



Jason Crees
04-25-2019, 12:08 AM
I am very new to lasers and am looking to add one ASAP. I acquired 500 double walled stainless steel tumblers for about $0.40 a piece and am wanting to engrave them. I mainly do woodworking and have a CNC. I could use the CO2 laser for other wood items, but the ability to add metal engraving would open up some new opportunities.

If I go CO2, I was thinling a 100-150W tube for cutting but would this be too much for marking the tumblers (with a Cermark type spray). I am looking at the Thunder Laser with their HR lens. Or would it be better/faster to go with a 30-50W ebay fiber laser? Would I need a rotary axis for the fiber laser?

John Lifer
04-25-2019, 9:55 AM
Sound as bad as Me:D
I got a pile of 8x12 slate hanging signs for cheap, just have to clean off old paper.

Search and read here, but for SS cups, Cermark and CO2 is going to be the best. Fiber, at least what I've done is SLOOOOOOOW and while looking crisper, is just not as good. Even a 30 or 40 watt will mark the cups. My 80watt is fine.....

Kev Williams
04-25-2019, 12:36 PM
C02 and Cermark for ANYTHING stainless that's bigger than a postage stamp, with the goal of black marking. Case in point, I just added import info to some SS ID plates. The 2" long plates only had enough room for 5.5pt text that took up 1.7" of the 2". It took my fiber 50 seconds to engrave each plate...

The 4" long plates had more room, I used 10pt text and Cermark, I set 2 plates side by side and ran both at once, the text took up 7.4" of the 8". Cermarking engraved 435% of the length and 181% of the height of the fiber's output in 50 seconds- by my math, Cermarking was 7.8x faster than the fiber.

And Cermarking is SLOW... ;)

IF you're looking at Chinese machines, 100w is about the limit where you'll still have useful low-power functionality. My 80w Reci engraves black Romark at about 10% power, once down to 7 or 8% a DC laser won't fire reliably--

But bite the bullet and spend the bucks for an RF machine and you have a much higher power limit and still have good low power use...

Jason Crees
04-25-2019, 12:49 PM
Thanks for the info! I have been told by dealers/sales people that a 100W CO2 laser will be able to easily cut 3/8-1/2" plywood (assuming it is good and not filled with voids) and wood with air assist. Can anyone confirm this is the case in the real world use and not just salesmen talk?

Gary Hair
04-25-2019, 1:44 PM
My 30 watt GCC would cut 1/2" acrylic but the problem was that it would take all day long to cut much of anything. So technically, yes it would cut 1/2" acrylic, but you could never make money doing it at the rate it cut. I have cut 1/2" mdf with my 80 watt Trotec and it works quite well, much faster than the GCC cut acrylic. But I still wouldn't want to try and make money doing it. Kev could probably answer this part better than I, but maybe a glass co2 would cut wood better/faster than my Trotec, but even if it could I doubt it would be profitable. I cut a lot of 1/8" mdf/hardboard with the GCC and the Trotec and a fair amount of 1/4" with the Trotec - still slower than I'd like and hard to make money doing it. If you want to cut plywood, and make more than minimum wage, get a laser suitable for the task - 200-400 watts (or more), then buy a lower power machine for engraving - the right tool for the right job is really fitting in this instance.


Thanks for the info! I have been told by dealers/sales people that a 100W CO2 laser will be able to easily cut 3/8-1/2" plywood (assuming it is good and not filled with voids) and wood with air assist. Can anyone confirm this is the case in the real world use and not just salesmen talk?

Kev Williams
04-25-2019, 3:51 PM
^^ What Gary said :)
--cuz you'll never find ME arguing
against getting more machines :D
408652

Rob Damon
04-25-2019, 8:25 PM
My 100w chinese CO2 will and has cut 1/2" plywood.

Kev Williams
04-26-2019, 12:14 AM
My 80w Triumph/RECI cut these--

408673

408674

--I'm not sure what wood the top piece was, looks like oak? -- it was 3/4" thick,
the bottom is Cherry (obviously), 20.75mm which is .817" --

Of note-
I overdrove the tube slightly, 27mA if memory serves-
VERY slow, I think it took like 30 seconds, maybe more, but did both in one pass.
and on both pieces I used a 2" lens, and no air assist. I tried doing this with a 3" lens, never got more than about 5/8" deep, and more passes just made charcoal out of the kerf.

Jason Crees
04-26-2019, 1:09 AM
Thanks for all the great info! Does any one have experience with engraving with the Thunder Laser an the HR head (I believe 1" lens) and a 130w laser? I haven't been able to find much on their HR head.

Scott Besaw
04-26-2019, 11:48 AM
Thunder laser's HR head has a finer dot and will engrave pictures better than a 2" head. A 2" head is fine for lettering and general engraving until you get around 1/8" and under and then it depends on material. Most of your engraving will probably be done with a 2" head. You will also want to buy the rotary for the tumblers if your engraving has any size to it.
I have had a 100 watt Nova 35 for 2 1/2 years and it has been a good machine. The laser was set up accurate and there were no loose screws or bolts.