Pinnacle ZX engraving erratically...

[James Fillmore]

I use my laser to laser cut foam, foam rubber and plasticy foam (like the white bubbly thick sheets that protect a computer inside the cardboard shipping box).

This last material, the plasticy white sheets, approx 1/4 thick, used to cut GREAT. Now if I cut a square, it will engrave fine for about a 3/4" then the power seems to drop off to like 50% and it doesn't cut through for about 1/4" then it will cut fine again for the next 3/4" and do this all the way around the square. Not good. Odd thing is, if I set the speed at 3.2%, 100% power, it cuts perfect. If I just drop the speed to 3.0% or lower it does the pattern described above. Odd thing is if I drop the speed to 1.0% is barely cuts all the way through. In fact 3.2% speed cust BETTER than 1.0%. Basically anything under 3.2% cuts the same. Odd?!?!

I also noticed at 3.2% I can set the ppi to say 45 and watch the laser led indicator on the main panel flash at 45ppi. But when I change the speed to 3.0% or lower the led comes on with a constant glow no matter if I set the ppi at 30, 45, 500, etc.

I have firmware 3.25 (I see LaserProna.com has a rev 3.28 but I can't access it and don't know what the changes are). I also have Windows XP driver 3.55.

Not sure whats different other than something changing over time.

Again, everything appears fine and appears to cut just like always as long as I have a material that cuts well at 3.2% speed and above. Below that it appears to be at like 1/2 power? For reference I used to cut through this white plasticy foam that was 3/4" thick NO PROBLEM at like 0.7% speed, 100% and 500ppi. Now, it absolutely will not cut even at .1% speed. Again, acts like 50% power under 3.2% speed. Machine is 2 years old and I use about 40+ hours a week. So about 5000 hours on it.

Any ideas? Anyone else see this?

Kevin? :)

(PS The major beam alignment worked GREAT Kevin. The above problem is NOT beam alignment, dirty lense or mirrors either)

[James Fillmore]

After a TON of testing I fond that the laser won't cut properly at 100% power setting. It actually cuts properly at the 90% power level. In fact if I reduce the power level to 90% and the ppi to say 45, I can see the laser indicator plse at the 45ppi rate.

Am standing here by the laser testing and I jst ran a test at 80% power and it cut just as well! 70% power cut the same!!! Bumped the speed up from 0.6% to 0.7%, 80% power and 500ppi and it cuts the same! At those settings it cuts like it always did at roughly the same speed and ppi but I ALWAYS left the power at 100%.

Just tried the same setting as my last, great cut, above but changed the power to 100%. Gave me that same BAD stitch cut. 90% worked fine. 80% works almost the same. 100% doesn't cut!

Whats up Kevin?

[Robert Ray]

If this was happening on the Rofin DC35 lasers at my day job, I would do a CO2 gas change first, test again, try a PWM calibration, then replace the PWM module if it persisted.

If it happened on my Laser Pro, I would suspect the laser needs recharge, but call service and ask if they seen this before, suspecting the laser, power supply, or PWM control as culprits.