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The laser head from Creality is likely to disappoint you. I don't know if they mentioned cutting speed in their material, but based on my experience with my 100W laser cutter, 3mm ply cutting speeds will be in the range of a few mm/sec. I haven't tried cutting comparable PWB fiberglass, but would guess that it cuts very significantly slower. I don't know the wavelength of the creality laser, but the CO2 laser in mine will effectively not cut metal at all. On most metals it will not even leave a mark. By coating the metal with appropriate materials you can make a mark, but it is more of a fusion with the surface than material removal. Some wavelengths will interact better, but generally kW of laser power are required for cutting applications.
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That's absolutely correct. Unfortunately, metal cutting or etchning with a laser needs a lot of power and the required laser source is not sold by Creality.
And when we talk about power, this means optical power, not electrical power, as usually indicated on Aliexpress.
Furthermore, the optical power is actually a peak power when speaking about a pulsed laser source, or a CW power if the lasers' output is a...CW.
The metal cutting domain for CO2 lasers usually begins at 400W optical power, (which means at least 4-5 kW electrical input power). But the fun only begins at 2 kW CW. You will also need 2500 l/h of process gas (Ar, N
2, O
2).
For high speed sheet metal cutting (0,8 mm steel), 6 kW CW optical power is standard. If you build an oil tanker with 10 cm thick steel, 20kW CW is definitely required.
CO2 best works for iron/steel and also, with limited performance, for aluminium.
Pure copper or matter that contains copper is almost not machinable with a CO2 laser.
A good alternative for high power (> 1 kW) CO2 laser are Ytterbium (and other rare matters) doped fiber lasers. They are rather cheap, really handy, and have very good efficiency.
For YIG lasers or even NIR diode lasers, lower power values can be sufficient for metal cutting, but I doubt that anything is seriously doable below 250W for iron/steel/aluminium. For copper, significantly more power is required.
LKPF uses green laser sources (12W, 8W) and also a 355nm UVA laser (5,7 W) in their Protolaser series. But, as a 'pulse frequency' is indicated, these power values are likely average electrical values. The laser source is probably Q-switched, which leads to optical power values in the kW range. And that's probably the ballpark value required for pure copper etching, even at these relatively short wavelengths, down to UVA.
As a comparision, sheet copper soldering requises
a 1kW CW green laser.