MOPA or not

[John Lifer]

Well, I've got a line on some work that appears to be long term and will most probably need a fiber laser to accomplish. Got quote for three different fiber lasers from my favorite Chinese lady. I'm looking at a 20 watt as time isn't a concern at this point and from what I've gleaned from you guys past posts is that more power isn't needed except to reduce passes and thereby time.

But I'm intrigued by the MOPA laser. Potential for black marks without cermark is good, maybe colors? I say maybe as it looks like mixed results from these lasers. And I don't have use at this point for say a color logo, or marking.

So is it worth spending $1900 for black marking - which I could use now and a potential for a color job? And if I have the time, marking on plastics?

[Chris Bratton]

I have a 30 Watt MOPA that I'm selling because I bought a trotec. It does black, gold browns really good but the other color have been elusive to me. For me I do many one off jobs so the time to set up the job is crucial to me so I'm going with the trotec. Message me if your interested. Paid 15k for it in August. Sell it for 10K. Comes with servo rotary and 2 lenses.

[Kev Williams]

Did you leave a zero off the price? ;)

I've come to the conclusion that, with my 30wQ, if I want black I'll use Cermark. I've found that the knife blades I engrave for a few makers around here will go acceptably black using Gary's 'low 'n' slow' approach. Even then It's kinda like a 'hologram' black, as the black changes colors with different light sources and/or lighting angles. My knife customers think it's really cool. Then last week a guy brings me a big claw hammer. Low 'n' slow wouldn't turn it black for love nor money.

I'm THIISSS close to picking up another basic 30w unit because I have enough work to keep 2 of them busy, AND I need a spare machine in case of a problem.

But- I too am looking at getting a MOPA, a 60 watter. I've been getting many RFQ's as of late calling out for rather deep laser engraving, which I'd normally do via rotary-tool engraving. My 30 will deep engrave okay, but it's very slow going at best.

I'm curious as to how quickly a 60w Mopa would hack out a square inch to .015" deep. Just guessing, but my 30 would take close to an hour, maybe longer. I can do that with my IS7000 and cutter tools in about 2 minutes. But then I'm needing to sharpen the tool already, which eats up nearly as much time as the engraving ;) If a 60w MOPA could do a 1x1x.015 in say, 10 minutes, then I could justify buying one.

I don't know that I'd have any use for colored engraving, but if a MOPA would do a respectable black, that would be a bonus.

>edit<, as Chris beat me to the post :) -- So, does it deep engrave appreciably faster than a basic Q machine? (assuming you've owned/used a Q machine before!)