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View Full Version : Laser Advice - Glass V Metal C02 & Machine Choice



Rick Hughes
02-26-2014, 3:21 AM
Hi guys.

New to the forum and looking to get a laser engraver, as a bit of background we manufacture parts in-house that are anodized Aluminium. We would like to start putting our own logo's on the parts now and would happily send them out to get done but the problem is lead time - we just cannot afford for items to be away for a week for ano, then a week for laser etc so we want to do it in house. I hope you can help me with a few questions:

- What is the difference in terms of performance between the glass and metal tubed c02 lasers? - We wont run the laser 24/7 maybe a few hrs a day.

I ask this as i had a demo of two machines, one a 80w glass laser, the other a 40w metal, the quick demo led to the glass lasers engraving being 'rough' or blurry and patchy in colour in places while the metal laser was much more 'in focus' and had an even colour - the metal machine is twice the price.

- Machine choice? - We have around 8k to spend (we are in the UK) and our logo is simple solid text, i have also had requests to cut 3-4mm plywood so would need to be able to handle this too, i assume a 40w machine can do this (speed not paramount as this is a secondary job)

So, in short, we are after an affordable engraver that can engrave out logo onto anodised aluminium and occasionally cut wood, easy to use software is also nice the printer driver type i was shown at the demo looked very good.

Thanks in advance for any replies. Rick

Dan Hintz
02-26-2014, 5:50 AM
Even with a 40W machine, you could run it at full speed and still have room left over... anodized aluminum is very forgiving. The 80W DC tubes are right at the limit of what I would be comfortable with in terms of engraving (they have a much higher minimum power than RF tubes), but even so, who knows how careful the person was in setting up their machine. A loose lens/mirror or an incorrect focal height could easily create a ........ engraving... if the dots are well-defined but the edges are jagged, the piece was either run with too low of a dpi or the machine can't handle small steps without vibration.

Ply, however, typically wants as much power as you can give it for a clean cut. If it's an RF tube, however, you will likely get a better cut even at 40W...

If you want easy to use software or are easily frustrated, you need to look at a western machine (RF tube)... the Chinese (DC tube) stuff can be entirely too finicky for my tastes.

John Bion
02-26-2014, 9:00 AM
Hi Rick,
There are a number of us here from around the UK, some with western lasers and the rest of us with Chinese. If you let us know where you are, perhaps there may be someone nearish you who would be happy to let you see their’s in action.
For engraving, the western machines are top notch with tremendous ease of use and reliability. The glass tubed (almost certainly Chinese) lasers are good bang for buck, especially for vector cutting and the sub-80w tubes not bad for engraving but slower than western lasers. I have two Chinese lasers, they are ok but I am aiming for a top western brand next purchase around.
Kind Regards,
John

Rick Hughes
02-26-2014, 1:51 PM
Thank you for taking the time to reply guys.
The demo was quite quick, with one setup on the 80w glass and one on the 40w metal - It was basic text engraving and the glass lasers engraving looks blurry.

I suppose the real question I am asking is does the tube type make any difference to the quality of engraving as this is what I was told - that the glass laser would struggle to engrave anodised aluminium and was a cutting machine.
For reference here is what I was looking at:

The metal laser machine: http://laserprouk.com/laser-engraving-machines-spirit-ls.html

The glass laser machine: http://laserprouk.com/laser-cutting-machine-x252.html

There is a big gap in price between the two, the company seemed very good though, offering good support, they are local, software was good and the people I dealt with were all decent.

Anywhere else people would be looking with around 7k (not inc vat) to spend?
Oh, one last question - how much power do I need to get through 3-4mm plywood in a single pass, speed not important (within reason)

Thanks and sorry for all of the basic questions!

Kev Williams
02-26-2014, 2:19 PM
I've had my 'metal' lasers for 13 years, I've had my 'glass' laser since the day after thanksgiving. My glass laser is a big 1300x900 cutting machine, and it's been a learning experience! The difference between the two types of machines is akin to driving an old Peterbuilt with with a 5/4 manual transmission arrangement, vs driving a new Mercedes. But like with the Peterbuilt, with patience and practice, you can make a glass laser perform very nicely!

I'm betting the reason the reason for the blurry lettering is the backlash needs tweaking. Metal lasers are wonderful for NOT needing backlash tweaking, glass lasers (mine anyway) must have different backlash offsets entered into the software for different speeds. If not tweaked right, the laser will put down TWO images real close to each other instead of firing precisely in both directions. And two images are going to look blurry. I recently did a bunch of anodized tags, each of which had .045" tall ID numbers in one corner, and they looked fantastic. My LS900 couldn't have done better.

THAT all said, my suggestion, based on your needs, is to find a used 'metal' machine, and do without the big learning curve. They can be had for a reasonable price, and usually have lots of life left. Best example I have is my New Hermes Optima (ULS) 25 watter, which was my rep's trade-show demo and 'home-base' machine for several years before I bought it in 2001. I've used it daily since then, and all I've ever done to it was change out the laser tube, even though the old one was working fine at the time. Right now my BIL is running name badges on it, the past few days it's been doing hundreds of small SS ID tags. I paid $5000 for it, and it's made that money back MANY times over. It was the first laser I ever SAW let alone operated, and it was a piece o' cake. Learning to tweak a glass machine is a whole nuther ball game...

Rick Hughes
02-26-2014, 2:40 PM
Thanks for the advice, they have a metal laser machine on a pricing deal in stock there at the moment, with the rotary attachment we will need, I would love to find a used one but we may need it sooner....

Just one last newbie question - will a 25W machine be enough to cut plywood 3-4mm thick?

Thanks!

Dave Sheldrake
02-26-2014, 4:15 PM
Hang fire Rick, I'll PM you regarding that machine

cheers

Dave

Travis Wizniuk
02-26-2014, 6:07 PM
Hhmm sounds to me like something may have been wrong. I've been engraving anodized tags as well as guns (yes guns) with my G. Weike 80W and the quality is fantastic... I'm wondering if they didn't set the Scan Gap correctly in Lasercut (if they were using LaserCut). I definitely get blurry stuff if the scan gap is too high..

Rick Hughes
02-27-2014, 5:20 AM
Thank you for the advice all - nice to come onto a friendly, helpful forum once in a while knowing what other forums are like.

Will take a look around and make a few more calls and see what comes up - my main reservation at the moment is software, i do to much at work with setting cnc machines and dont want to have to set up another machine, i would rather somebody else can learn the process easily and then get on with things so this may be a deal-breaker for me.

Thanks, Rick