Hi,
first of all, this is my first post here, thank to you all that make this cummunity a great source of information for diy hobbyist like me.
I am new to cnc, I have built a DIY cnc milling machine and it is working great, exept that I have to get a better grisp on the software and programming side of thing, but that is another subjet, the machine is worling well on the 3 axis.
Then I tough, I will mount a cheap chinese laser side by side with the mill to be able to burn thing and make some cool looking thing I don't know what , but laser are cool.
So I bought a cheap 3000mw 450nm laser diode on ebay, exactly this one:
Focusable 450nm 3W Blue Laser Module TTL Carving/Burning/Engraning Gift Goggles | eBay
It come with a pair a safety glasses, that I totally don't trust! anyway.
Then I begin to have safety concern about operating, calibrating and playing with this laser, This is not a cheap 5mw laser pointer laser, from what I read, its a class 4 laser ( output greater than 500mw) and the more I read about it, the more I am aware of all the possible hazard and danger of this thing,
I will shop for a safety glasse for 450nm laser, but I don't know wich one to buy, there is a parameter on glasse called 'OD' that make the laser dimmer of a certain factor, but on the laser I am buying, it say nothing about what "OD" glasses I should buy, anyone have a tip on this? If I buy with "OD" too low, the laser will not be dimmed enought to be safe, and if I buy with the "OD" too high, I will not be able to see the laser at all, is that correct?
Also, another concern I have: If I can't look directly at the laser ( obviously) and I can't look at the reflection, how can I perform a good focusing of the laser beam , knowing that the focusing system is done by rotating the lens by hand? I have to see the dot?
I have read enought about all the potential danger of this type of laser, now that I know it and I am aware, I want to know how can I operate it safely, and that is where I am lacking information, I see everywhere danger, warning and hazard, but no where documentation about how to perform calibration and operation once you know the danger.
Anyone using this king of cheap laser ( this is not co2 , and the machine is not in a enclosure), can descripe to me how it operate it safely, and what glasses he is using to pretoect there eyes, I don't trust the 3$ one on ebay,
thank you very much,
Martin