Popping and Sparks when cutting 3mm 6061 alum..why? 2

[LaserProto]

Using a mazak 1500 watt flat co2 laser.
When Im cutting alum. Some areas cut ok some areas the laser pops and sparks, Is there a reason for this.
and what can I do to stop this. There for getting it to
cut cleaner. thanks

 

[LASERNINJA]

I would say that the cut condition is too fast. If the mirrors are dirty, or the focus isn't at the right spot it will decrease the maximum feed allowable.

 

[laserman16]

It is probable that your cut conditons are off. It could also be your mirrors, lens, nozzle gap.

I suspect though that it is not your mirrors/lens but your settings and you will need to ensure they are acurate. Be sure to start fresh with recommended cutting conditions and then go from there. Prior to this be sure to clean your lens, clean and re-focus your lens and set your nozzle gap.

If after all that you still have issues then go out and buy some pepto bismal, pour a small amount on the material and spread it around, let it dry and you should be ok then. The Pepto bismal removes the refectivness of the aluminum and that is what is causing you problems.

I got this tip from a technician and at first thought he was nuts until I put my head around it and it works perfectly!

 

[LaserProto]

What settings would you use for 3mm T6061 alum.
As of now my setting is S1300-P400-Q100-F350
Im new to laser cutting and not sure what the recomended
settng should be for alum. Also do you have recomeded settings for all mild steel as well?
thanks in advance.

 

[laserman16]

Pronto, you would be best to order a manual for your machine from Mazak Optonics. It sounds like your having to run blind and really need to get a manual.

You can contact Mazak Optonics at 1-847-252-4600. I have this information I can give you but to best of my knowledge we cannot post e-mail addresses etc. If you want contact site admin and see if you are able to message me with your info and I'll help you out.

 

[LASERNINJA]

It has been my experience that Aluminum requires full power full frequency and full duty. The only real variables are feed and focus.

I have not run a Mazak before, but if 1300 watts isn't your max... Turn it up.

Am I reading that correct, 12 inches per minute? If that is as fast as it will go something is wrong other than cutting data.

 

[msandoval]

When your duty cycles is set to 100% , the frequency (Hertz) is ignored, this means you are using 1300 Watts Continous Wave. If your duty cycles were 99%, then your frequency will play a role on the cut (Pulsing).

Laserninja is correct when he says turn the power up. I imagine your machine must be a 1500 Watts machine. 1500 Watts may be enough to cut 3 mm (or 0.125") aluminum. Specially 6061 since it's more of an alloy and not so much pure aluminum.

If you can't run faster than 12" or 350 mm/min, there is something wrong and you should either replace the lens or have the machine looked at to make sure it's actually outputting the right amount of power.

You should be able to cut this material somewhere around 1200 to 1500 mm/min with full power and about 8 to 10 bars (kg) of nitrogen pressure or even shopair (if available) which will make the cut a lot more stable.

Good Luck

 

[laserman16]

LaserProto, based on the Mazak manual for a 1500 watt MKII laser these are what your cut conditions should be if usuing Nitrogen:

P1500/Q500/R100 - Gas Pressure 12 - noxxle gap -3 - 50ipm

In your inital post you state you running at F350 but I suspect that was a typo.