Laser for very thin metal cutting

[Woodsy]

Hi everyone

So, new here, so go easy on me!

I have it in mind to make a rig that will cut holes in very thin metal, thin as in the same thickness as a coke can for example.

Now, I've found a 905 nm, 100W pulsed diode (CVD 167 TO5C)

http://skycraftparts.com/ebay/pdfs/cvd46-to18c_4502404.pdf

At this stage, I'm not worrying about driving it, as I can worry about that later. Being a diode, I expect fairly shoddy beam characteristics, but achieving a focal point of 0.1mm (diamater) or smaller should be possible with careful calibration and good optics. What I'm after is advice really. Has anyone used this sort of power at this wavelength?

Of course, I could just buy pinholes, but that is far less cool

Thanks in advance!

PS: apologies if this has come up before, I did a search and couldn't find quite what I needed.

 

[IsaacT]

You might want to consider getting a CO2 laser...thats what most people round here use for higher power cutting/engraving IIRC. Not too expensive either.

 

[Woodsy]

Just out of interest, how expensive is "not too expensive"?

 

[Benm]

Cutting metal is pretty difficult. Even a watt of 445 nm will hardly cut through a sheet of tinfoil.

The problem is mostly that metals are very good reflectors, so little power is absorbed. As they are also thermal conductors, whatever does get absorbed gets spread over a larer area easily.

CO2 lasers have the advantage of their long IR output, not all metals remain to be reflectors at that wavelength, so it least your laser energy is absorbed in the first place. Near-IR lasers will not have that benefit, as most metals remain good reflectors to very well over 1000 nm.

 

[IsaacT]

I think when I looked a ~60W CO2 was gonna run me about 400-500 dollars(on the lower end Chinese tubes), so about there.

 

[Benm]

Something like that - you could browse around ebay for those.

I guess the best option would be to buy somewhere you can pick it up yourself - CO2 laser tubes are expensive to ship and easy to break.

 

[Woodsy]

Wish I could, the UK is terrible for things like this... unless I spend a fortune with a UK based company, I have to import :/

 

[TheTeslaWarrior]

actually a co2 isn't that feasible. to cut metal you want at least 100W. 60W won't scratch it. also > 100W co2's will not be cheap, at all. as for pulsed, you need a good power supply and quite a bit of power. look into ssy-1s if your interested in pulsed lasers. they range about 200W pulsed however i have only gotten mine to poke hole in aluminum foil.