Metal Cutting on CO2 Laser... am I mad?

[Russell Collins]

I design clean combustion heaters and cookstoves for Indian usage generally (although now looking to make some local products here in Australia) and all our production in India happens on industrial lasers. I decided to improve the prototype to production pathway by getting myself a large bed laser (1500 x 3000mm) with a Metal Non-metal hybrid setup. It has a 300w CO2 YongLing Laser and the Ruida 6332M controller with Live Focus. So far so good... kinda. Learning curve is steep, so I'm here to learn from those who have paved the way ahead of me. Happy to share successes and learn from those with more experience than myself.

[Pete Cyr]

Welcome Russell - be sure to back up your vendor settings - they are easily lost and difficult to recover.
You are not mad. You have a goal and seems you are on the right path to meet your goal.

[Gene Uselman]

I am very interested in metal cutting with a CO2 laser and would love to see a conversation on the forum about them- we occasionally gain a member with this equipment but seems that as soon as they get them operational they move on with their lives. We have a lot of CO2 knowledge and may be of some help. Gene

[Russell Collins]

Welcome Russell - be sure to back up your vendor settings - they are easily lost and difficult to recover.
You are not mad. You have a goal and seems you are on the right path to meet your goal.

Thanks Pete... Actually I seem to have a software glitch already and can't find firmware for the 6332M online as yet. Do you have any ideas about where to track this down?

[Russell Collins]

I am very interested in metal cutting with a CO2 laser and would love to see a conversation on the forum about them- we occasionally gain a member with this equipment but seems that as soon as they get them operational they move on with their lives. We have a lot of CO2 knowledge and may be of some help. Gene

Ok well I'll be happy to share what I find out as I get it working. So far I have had partially successful cuts in up to 3mm mild steel... partially in that sometimes the cut is good, and sometimes the cut is blown out. I'm waiting for the gas supplier to arrive with laser purity O2 and have read that the quality of the steel is quite important. I can see that the 300w is capable of doing the job, but my experience so far is that getting the settings exactly right is super critical. I had achieved quite decent cuts in 2mm mild and 1mm SS before the machine glitched out on me. Now trying to work out how to do a software update.

[Pete Cyr]

Welcome Russell - be sure to back up your vendor settings - they are easily lost and difficult to recover.
You are not mad. You have a goal and seems you are on the right path to meet your goal.

Thanks Pete... Actually I seem to have a software glitch already and can't find firmware for the 6332M online as yet. Do you have any ideas about where to track this down?

No - I will look around this evening.

[Russell Collins]

I am very interested in metal cutting with a CO2 laser and would love to see a conversation on the forum about them- we occasionally gain a member with this equipment but seems that as soon as they get them operational they move on with their lives. We have a lot of CO2 knowledge and may be of some help. Gene

I'm starting to get some acceptable cuts with steel and one of the things that surprised me is that I've had to dial down the O2 quite a bit as compared to the many suggested rates of pressure. Seems the excess O2 was just blowing out big sloppy burns through the metal when it actually needs only just enough to get through and surplus is detrimental. When I've got something to show I'll do more of a comprehensive post about this.

[Gene Uselman]

Thank you Sir. Please keep your thoughts coming, too much O2 would seem counterintuitive. Gene

[Russell Collins]

OK so its been a while since the last update. Finally after several months I seem to have nutted out clean cuts in 3mm mild steel.

I was getting so despondent that I even made a call to the dealer for Kern lasers and got a quote (about the same price as mine, except with an extra 0... ie, 10x the price). Hmm... back to fiddling about.

This is what I did: 2.5" lens swapped out for a 4" lens, curve up as suggested on most forums. This seemed slightly better, but I was still not really getting results to be super happy about.

Laser O2 (high purity low moisture) set to 20psi (lower than some others suggest, but this seems to work best).

Then just last week, still not happy with the overly sloppy inconsistent and burnt out cuts, I decided to swap the lens around and tried it curve (convex face) down.

WOW!!!! Suddenly I have a machine that is doing those kinds of cuts I was dreaming about after seeing YouTubes of high end fibre lasers! Well, perhaps not quite that good... but as compared to what I had been getting, this is a revelation.

Final Settings: 4" lens, flat side up, focus at 2mm, O2 at 20psi, cut speed at 10mm/sec, power at 80% max / 70% min and 3mm MS is cutting like butter with a 300w CO2 from China (at 10% of the cost of a Kern 400w).