looking for a cutting laser

[liquid98]

Hi,

I'm planning to build my own CNC machine to cut aluminium (4-10mm).
I'm looking for a laser that is capable of cutting this material, so if someone
can point me to manufacturers (resellers)of this kind of laser, I would be very pleased.
Thanx in advance

[MacGyver]

YAG, 100W+ would be a good start.

[laser3kw]

one of the best is Trumpf.
I had a 3000w (co2) it would cut 6mm but 10mm was a50/50 chance. I would have at last 4000w to do 10mm - for clean cut -with any speed and a no dross exit. Also your steering path and focus can not deviate one mm! spot size must be maintained or cut will cease and backfire in to the lens .

[MacGyver]

Originally Posted by laser3kw one of the best is Trumpf. I had a 3000w (co2) it would cut 6mm but 10mm was a50/50 chance. I would have at last 4000w to do 10mm - for clean cut -with any speed and a no dross exit. Also your steering path and focus can not deviate one mm! spot size must be maintained or cut will cease and backfire in to the lens .

No sane hobbyist would ever use a CO2 laser to try and cut aluminum thicker than a few mils (thousandths of an inch, not millimeters), and they certainly wouldn't be able to afford a multi-kW system (approaching $1mil). YAG would be orders of magnitude less expensive, faster, and more energy efficient.

[liquid98]

Originally Posted by MacGyver No sane hobbyist would ever use a CO2 laser to try and cut aluminum thicker than a few mils (thousandths of an inch, not millimeters), and they certainly wouldn't be able to afford a multi-kW system (approaching $1mil). YAG would be orders of magnitude less expensive, faster, and more energy efficient.

Hi MacGyver,

YAG is a type of laser, where should i buy one? What brand can you
recommend?

Thanx

[laser3kw]

Had a Yag too! I think it was a RCA of something... that was 15 years ago. It was slow and problematic. Got rid of it for that ... and the potential blindness by the wavelength that was used. Almost got dropped by an insurance company.

[MacGyver]

Originally Posted by laser3kw Had a Yag too! I think it was a RCA of something... that was 15 years ago. It was slow and problematic. Got rid of it for that ... and the potential blindness by the wavelength that was used. Almost got dropped by an insurance company.

Potential blindness? Dropped by insurance company? None of your posts make any sense!

Pretty much all lasers we would ever talk about in here are a blinding hazard, even at 1W. You're talking about 3kW CO2 lasers and say your insurance company almost dropped you because of the wavelength on a YAG? That's the dumbest thing I've heard this week... did they think the wavelength on the CO2 was eye safe?

I'm starting to question if you've ever done more than read about lasers in a magazine, not to mention actually use one in a production environment.

[laser3kw]

"Potential blindness? Dropped by insurance company? None of your posts make any sense! Pretty much all lasers we would ever talk about in here are a blinding hazard, even at 1W. You're talking about 3kW CO2 lasers and say your insurance company almost dropped you because of the wavelength on a YAG? That's the dumbest thing I've heard this week... did they think the wavelength on the CO2 was eye safe? I'm starting to question if you've ever done more than read about lasers in a magazine, not to mention actually use one in a production environment."

Boy,you know how to make someone feel "welcome"
My purpose here is to share my experience with others who are trying to answer questions or at least help them research answers(give a man a fish...).
I can assure you I have installed, setup, run, torn down and rebuilt industrial lasers and cnc equipment. My profession is electrical/ mechanical engineer. I sure using the word "engineer" makes some people uncomfortable

"None of your posts make any sense!"

I am sure not everyone has the same experiences in life. Likewise, some have never worked in an industrial atmosphere, let alone high powered equipment. And I can see why some of this doesn't make sense.
I assumed that everyone automatically has some background and identifies with what is presented. All lasers are potentially blinding hazard - yes,even laser pointers. My assertion was that everyone knew that CO2 wavelength (Far IR- 9600, 10600nm) is reflected by glass or standard shop safety glasses. Therefore if your company has standard safety polices regaurding wearing of safety glasses, then your insurance company probably won't raise an issue. But because a Nd:YAG has a wavelength of 1064nm, it's scattered and reflected beam WILL PASS THROUGH glass or safety glasses. Some CO2 industrial laser are installed with enclosures that have plain lexan panel as a safety precaution.
But, if it is of any comfort to you, I did dig up some old files to see if I misstated something(from 15 years ago).
It wasn't a "RCA" it was a Raytheon 500 watt pulsed, Nd:Yag class4, 1064nm wavelength. It was a open path system, not fiberoptic.
We had it in an enclosed room, and had to wear laser safety goggles just to be in the room. Safety lockouts, warning lights, the whole movie type miltary installation schpeel. The reason for that is at 1064nm wavelength and that wattage, there is a high likelihood of dispersing if a cut is not initiated and the energy is not being absorbed. I.E. a room full of scatter, high power, primary wavelength and harmonic wavelength, that will pass through regular safety glasses.
That was the safety rules setup by the laser system manufacture. The supplied documentation spelling out the eye hazard with "blindness" highlighted in every instance. Scare tactic? Probably, but I do know the insurance company was real edgy after reviewing the specs. And I won't take a chance with my eyes trying to be "Macho". The manuals were compelling enough not to challenge them.
As for our other CO2 lasers we had a Trumf 3000w rf pumped, a Rofin-sinar SM1700,2000w fast flow and a Coherent 750w.

I did a search for the obvious - as I am sure ANYONE can- and here is some information on the wavelength that was used:
Neodymium-YAG lasers produce 1064-nanometer near-infrared light that can cause severe retinal damage, and because it is invisible, the likelihood of injuries resulting from reflected beams is increased. Most of these lasers are diode-pumped and produce short intense pulses, which can produce injuries when even a single reflected pulse enters the eye. Therefore, eye protection that blocks all potential paths to the eye should be employed. Infrared-blocking protective goggles can be designed to transmit most visible
light, except for applications in which the higher-order harmonics are utilized. Frequency doubling can produce the second harmonic at 532 nanometers (visible green light), which is also transmitted to the retina, and when this emission line is employed additional filtration to attenuate green light is required. Frequency tripling and quadrupling is often applied with Nd:YAG lasers to produce third and fourth harmonics at 355 and 266 nanometers, presenting different hazards, and requiring ultra-violet blocking safety goggles, and possibly skin protection to prevent burn injuries. For example, lasers that generate several watts of power in the infrared, outputs of hundreds of milliwatts can be achieved at the second, third, and fourth harmonic wavelengths.Although some diode-pumped neodymium lasers produce relatively low power (especially at higher-order harmonics, when operated in continuous mode), most generate sufficient power to cause injuries, and eye protection should be worn when working with any laser of this type. A difficulty with any laser that generates multiple wavelengths is obtaining appropriate goggles to attenuate all dangerous emission lines. When higher-order harmonics are being employed, it cannot be assumed that light at the longer-wavelength fundamental frequency is not present, and many commercial lasers include one or more specific mechanisms to remove the unwanted radiation optically. Additional electrical hazards exist in neodymium lasers that utilize lamps for pumping instead of diodes, because of the presence of higher power supply voltages.

A considerable amount of research is being conducted to identify alternative crystalline hosts for neodymium doping, and as other materials appear in commercial lasers, special consideration is required for safe operation. As new laser types are introduced, safety devices optimized for their specific characteristics may not be initially readily available. Currently, the most widely used alternative to yttrium aluminum garnet is yttrium lithium fluoride (referred to as YLF), and both pulsed and continuous Nd:YLF lasers are available commercially.

[MonoNeuron]

Hi laser 3KW
Welcome to the forum (I may be a bit late though :-) )
I like your posts and think they are very informative so keep up the good work. MacGuyver is very passionate and likes to inform people about what he knows and maybe sometimes it comes across a bit "in your face" but it's all good information and thats what we like here. Sometimes the only way to get the good info is from the people who are actually in the business, so keep it coming. I will be lurking.
regards
Richard

[Laser.Tech]

3kw, always great to see another industrial laser guy. Welcome!

On to the original question: 4 to 10mm is THICK. A industrial CO2 of 1 to 5 kw would be the tool usually used. I'm not sure if anything under 500w is even going to touch it. Even if it did, it would be VERY SLOW. So if this is for hobby use, good luck but I'm afraid your goals are unrealistic.

And finally, YAG's are NOT a good choice for any hobby use. laser3kw is quite correct about the eye hazard situation. And insurance companies DO get nervous about them (first hand experience). And a YAG is NOT more efficient than a CO2, or cheaper!

Laser.Tech
(industrial laser technician (degreed) working with YAGs and CO2s for +15 years, including design work. In case you wondered....)

[Independent CNC]

Liquid98,

I would suggest that you look at some kind of punching machine because you would be able to punch way faster than you could laser. If you’re worried about edge quality you could go with a combo punch /laser machine. Trumpf in my opinion would be the best solution for either route you choose.

Independent CNC Programmer
www.ctcn.net/~3kings/

[MacGyver]

laser, my apologies for jumping on your case... the "holidays" have been making me a bit punchy, so I've tended to read things with less of a grain of salt than I probably should. You should see some of the posts I finished in some other forums but never hit the submit button The situation you describe with the insurance seems quite plausible, so I'll go have an extra glass or two of eggnog and wait for the "season spirit" to hit me.

Happy Holidays everyone!