Resonator questions

[ant42onia]

Concerning a 1000w Mazak Turbo 48x

My company does not have support from mazak, nor any trained people in the area to talk to, so any help you can give would be wonderful~

For starters I need to ask again about the laser 'mode'. I'm looking at pricing power meters and am confused about what exactly we need to check. Do we need to check the power output? Shape of the beam? Energy output? And is there a way to know the wavelength of our laser, or is that even important?

Once we can get a power meter - what can we actually do about the resonator? My boss wants me to cut aluminum even though I've told him it's not a good idea, and if something does actually happen to the resonator, what are our options?

Thanks for any input at all; I've been working on this laser for a year and still don't know much about it as the company will not pay for training.

 

[Timelord]

ant42onia,

I'm by no means an expert on welding lasers, we build lasers for paint stripping and do some weapons work, but I will take a shot at answering your questions. First, your 1kW laser, I'm assuming is a CO2 laser. Its wavelength is fixed by the lasing media at 10.6 microns.
The mode number of a laser beam is one measure of the beam quality. A mode number of one is a gaussian beam and the most focusable. As the mode number goes up, the beam focuses to a larger spot. A laser with a large mode number tends toward what is called a "top hat" profile that is, uniform intensity across the beam. This is what we use for paint stripping. Keep in mind that the focusing lens focal length also has a role in the ultimate focal spot size, that is, the shorter the focal length, the smaller the achievable spot, but conversly the shorter the Rayleigh range (the length over which the beam is considered focused).
For beam diagnostics, a beam profiler will show you the intensity across the beam profile which is an indication of the mode number. A power meter just measures total raw power in Watts. The beam intensity is the power divided by the beam diameter at the focal spot, expressed in Watts per unit area. For general diagnostics, a power meter is usually all you need to tell you if the laser is performing up to par. The beam shape and profile can be monitored by making short burns in a suitable material with the unfocused beam. We use acrylic for this purpose.

Timelord

 

[IRstuff]

So long as the laser is still cutting, it's at the correct wavelength.

The two critical things are indeed the power and beam shape. Doesn't your laser have something that monitors output power already?

Beam profiling is nice, but burning a spot on "burn" paper will give you a gross diagnosis, but so will inspection of the cutting kerf. You could simply keep a sample of a cut made with the laser working properly and compare that against future cuts. Likewise, the same sample can be used to grossly determine whether the laser energy has dropped, but it would have to be a fairly significant drop to be visually noticeable.

Killing the resonator is a bad thing to do. The resonator is the where the laser starts its lasing, so dead resonator means rebuilding the laser.

TTFN

FAQ731-376

 

[laserman16]

ant42onia, when you say your company has no support from Mazak does this mean they will not assist you?

If you want to gauge your power you need to purchase a power probe. This can be done via Cascadelaser.com. When you get the probe you can run a test to determine your power output.

If you believe you need to have a refurb completed you will need to call Mazak and make the arrangements. The costs for this are very reasonable.

I'd be happy to speak to you via private messaging on this matter should you wish to. I suspect I can assist you better in that format.

 

[ant42onia]

Thanks for the help. Unfortunately our request for the power meter was denied for bugdet reasons again - and they still want to cut aluminum even though it sounds like it may cost us more in the long run.
But at least we'll know what to do if it does go south on us.

 

[laserman16]

Sorry to hear that ant42!. Considering the cost for the power probe in minimal it will definatly cost them more and then I guess you'll get your wish..lol.

A real shame so many in mgmt chose to not listen to those who know the equiptment best.

Good Luck

 

[msandoval]

It has been said that "Capitalism (company/corporation) has no allegiance to anybody (employee)". Well, "Loyalty doesn't pay the bills" either.

My dear friend, I have seen your posts before and all I can tell you is you really need to look elsewhere for the opportunity and the support that you need.

It doesn't sound you have a sound management team above you and they are nickel-and-diming to get by, not to mention they want gigantic results with a machine that only has 1000 Watts of power, you don't have enough training or someone with experience that can guide you in the right direction.

It is remarkable to me you have taken the initiative to get the job done despite all the hurdles that are put in front of you and this speaks volume of your work, but at this point all I can say is to look for a company that can provide you with all the tools you need to showcase your talents and help you and them grow.

Best of Luck to you

 

[laserman16]

Very Well said msandoval! and I agree with it totally. I've been there before and it won't change for the better.

As there is a complete lack of skilled operators available you'll have no problems at all in obtaining gainful employment elsewhere.

However be sure to INTERVIEW the employer and not just be the interviewed. Take my word on it and trust that is goes along way in helping you make the best decsion on where to continue your career in laser processing.

Best of luck!!

 

[1plus1]

For an explanation of laser beam mode, or also known as laser beam profile, check out this site:

http://www.spiricon.com/techinfo/publications/industrial/applying_beam_profiling.shtml.

I am not familiar with your Mazak, but I have operated Trumpf, Cincinnatti, and Amada lasers since 1991. I perform minor maintenence and beam alignment. A good laser profile is essential for optimum performance and is a sign of resonator trouble. It will show if your internal optics are in need of replacement. If the profile and power are good and your cut is bad, it is proof that the trouble lies somewhere down the line past the resonator (bad cutting conditions, focal lens,bending mirrors, etc.). To check mode you need to burn a shot into a piece of acrylic about two feet past where the beam leaves the resonator. You have to remove the beam delivery tube. This can be dangerous so proper training and specific methods pertaining to your specific laser is essential. Your manager will have to get a technician to perform this and you will have to take notes to perform this in the future. He will show you how to align the beam down its path. There are laser beam analyzers you can buy that check profile, shape, average power, etc. that you connect to a laptop if you want to go high tech. Expensive, too. If your company wants to maintain a laser, I recommend doing a mode check at least every six months or whenever cutting quality diminishes considerably. If your manager is unable to do this, financially or otherwise, your only other option is to make sure focal lens is good and clean, focal point is correct, proper tip installed, and cutting conditions correct(assist gas pressure, speeds, power settings, focal point, etc.). This is all an operater can do sometimes. Have fun trying to cut aluminum with only 1000 watts. You better hope it is thin and remember: Go Slow. Don't lose the cut. A power meter is good to have, but not essential if you're not going to perform internal optics replacement. It checks power after an output coupling change so you can calibrate the power setting on your machine.

 

[ant42onia]

Thanks very much for all the help. If you would believe it, this forum has been the best resource I've had available to me.
I am thinking of moving on from this company as it is unreasonable to continue to ask for so much help from a forum board if my employer will not provide training oportunity. I was hired to just operate a CNC mill and ended up getting a laser - It's been most interesting.

I have learned quite a bit from this board, and thank you for bearing with me on all these questions.

 

[laserman16]

My advise - stay with laser's. The market for skilled workers is very small and job security wil lbe high for you.

Best of luck!