How can I cut 8 mm plywood with Sculpfun S30 10 W
Not easily. Try fast, at least 600mm/min at 90% and do tests how many passes you need. I guess you will need 8-15 passes, depending on type of plywood.
10W lasers are not very suited to cut that thick plywood.
I saw a video where some guy cut 18mm ply with an S30 Pro, 100% power but speed not stated. It looked like about 10mm/min, VERY slow. Can you imagine how bad that is for the machine?
I wouldn’t say that is bad for the machine - it just doesn’t make much sense As usual, you can take any laser to the maximum, and maybe cut 18mm ply as well. But it them might take 20 passes at very low speeds. So, a simple project already might take hours to finish. If time doesn’t matter, that might be fine.
Regarding running at 100%, that’s a never-ending story. I guess there won’t be any definite answer since one would need to test all those modules running continuously for months and years to check if the manufacturers statements are correct. Personally, I’m fine running at about 85-90% maximum.
Maybe one thing to add – it’s not the percentage that will cause the diodes to die, it’s the temperature. So if you can make sure the diode will never exceed 25°C, you can run it at 100% for 10,000 hours. But since most are cooled with ambient air, temperatures above 30°C are reached fast, and that will decrease laser lifetime.