As I learned yesterday, the brand new mirrors in our 80 W machine (glass tube) at Dim Sum Labs are of type K9. According to k40laser.se, a K9 mirror “is the worst mirror you can ever put in your machine.”
I am happy to buy new mirrors from China, which is just across the border. On k40laser.se, I found:
Si mirror: “Good reflective index for our machines (less than 50w)” – I assume for 80W, it’s not suitable, or is it?
On Taobao, 20 mm Si mirrors are dirt cheap at less than 40 RMB a piece (ca. 5 EUR / USD). Could they be fakes or of bad quality?
Mo mirror: “Good for up to 100w+ lasers.” – Is this the one to get?
Cu mirror: “Copper mirror, better than MO, a bit below SI when talking about reflective index” – Or better this one?