Got a new tube, got it installed, got it aligned (maybe the best alignment we have ever had!)
Started to do the glasses for our party (on Saturday!). The old laser tube would engrave them at 5%. Slightly defocused, looked great!
New laser is at 30%, increased lines per inch from 250 to 375. Still getting horrible striation. And just barely etched. If I defocus at all, I lose all etching. Not sure what could be so different.
Going to muscle through so we have something for Saturday (only 12 glasses) but want to trouble shoot it. Could tubes be that different? Thinking I could do a ramp test, as I seem to be loosing any lasering at any slight distance change.
One thing I noticed, if I go below 10% I get no mark on the glass at all. I have to go above 10 to see anything at all. The RUIDA controler shows 10% power. That is not a bottom limit, is it?
Any other ideas?
Using APC lenses on Omtech 50W laser. TEN-HIGH 50W CO2 Laser Tube 800mm D50mm.
Not only that, you can lift a defective tube right out of its shipping crate.
Do a test to verify TEM00 resonance at 30% power or so. This lengthy thread covers the territory:
You want a scorch on paper, not a hole torched through, so set the pulse power and duration from the KT332N display:
Then the Pulse button on the display will do the same thing every time and you can adjust the time & power for useful results.
Glass is tricky, so see how it behaves on paper.
However, glass CO₂ lasers typically do not fire below about 10% of their rated power, so it’s surprising the previous tube did anything at 5%.
And if these are new glasses, then the material will almost certainly be different and require some fine tuning.
My guess remains a bad tube, though.
That’s going in the wrong direction, because the focused spot is typically around 0.2 mm = 127 LPI. Using Line Intervals much less than 0.2 mm (or much more than 127 LPI) overlaps each trace with the previous one, which can lead to overcooking & cracking the glass.
That’s going in the wrong direction, because the focused spot is typically around 0.2 mm = 127 LPI. Using Line Intervals much less than 0.2 mm (or much more than 127 LPI) overlaps each trace with the previous one, which can lead to overcooking & cracking the glass.
I actually want them to overlap, as this will eliminate the obvious striation I am getting.
Same glasses as I have used before. We do the party every year, so we stocked up!
