A quality diode laser should last 8,000 to 15,000 hours of actual use—that's 10+ years for most hobbyists. The diode itself can last for many years, but the module lifetime depends heavily on how it's driven and where it lives. This does not always look like sudden failure—more often it's gradual. The good news is that modern laser engravers last much longer than most people think. Obviously it depends on use, but generally that's what is expected. 10 hours for either is a lemon, dud, broken, not to be. I kind of new to the laser engraving world and I have a piece that's gonna run for an extended period of time (about 60 hours) is it safe to let my diode laser run that long at about 60 or 70% power? Is it a very big project, with a very slow speed or lot of passes? Cut or engrave? A run of one.
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