About mirrors, laser head

[DocAndMed]

Hi all, i have some questions about mirrors and laser heads.

I see some people using HD disks like mirrors
- are they better than a cheap chinease mirrors set?
- machining this metal with normal industrials millers will not affect his shape and create internal bendings(caused by mechanical force of miller) that may affect superficial reflection or reflection precision?

How do you advice me to fix the mirror to a mirror mount?
- i thought to use two o-ring and between them the mirror or the lent and fix all like a sandwich with a perforated plug which is screwed to the mount, may work?
- how much get hot mirrors and lents? may they melt o-rings and affect precision?

I see small laser heads without a regulated mirror mount (like this: 404 - File or directory not found. ... M1-500.jpg)
- are they good?
- how much diameter need to be the output hole?
- how much distance is adviced for the offset(distance between nozzle output hole and material)?

Thank you.

[Randal_Kjolseth]

I have been using mirrors that I derive from hard drive platters for more than a year now. I can get about 8 mirrors from a standard computer hard drive, which I cut out using my cnc router. Mine are 20mm in diameter. They are very easy to clean as one can use just about anything to clean them, and they are very reflective. I have not had any problem with warping or heating up. And the best part is, they are FREE!!! Mine just sit in the mirror holder and the retainer is screwed on to secure the mirror.

[DocAndMed]

Thank you, can you tell me which type of mirror holder do you have? and if it use orings?