Need Laser Unit

[watzmann]

Hii All ,

actually am having a cnc router machine , i made it myself , i thought as many here to add a laser cutting unit to my machine , but i don't know where to find this unit ,

can anyone help me please to find a source which sell such a component?


Ali

[iyerks]

check out syndrad.com or coherent.com, they have lasers which could cut most materials.

Regards

Iyer

[jetstuff]

I think that should be http://www.synrad.com/

[christo]

Hello!

What kind of output in terms of power do you need? What are you going to cut? A CO2 laser resonator is in most cases stationary due to it's sensitivity to vibration and it's size. You use mirrors and lenses to move and focus the beam. This is tricky and expensive but it can be done.....

Christo.

[Syp]

Not true! Synrad now has 20 and 40 watt rf excited sealed lasers that weigh less than 15lbs, have fixed mirrors, and could easily be mounted to a medium sized gantry. This has the advanage of simplicity and much easier setup/focusing, but probably at the cost of significant decrease in speed.

The only problem is, they are around $5k to $8k new. :-(

I don't think there will be an open source rf excited laser project anytime soon...

Syp

[rolandf]

Be sure to match the type of laser to your application. An example is NOT to use CO2 to cut aluminum. This can be dangersous since the laser will melt the aluminum which when it turns into a liquid will reflect the beam. The material being cut must always absorb the light radiation in it's solid and molten form. Also be sure to buy yourself laser safety glasses matched to the light frequency of the laser.

[Syp]

rofl

"laser will melt the aluminum which when it turns into a liquid"

*giggle*

Much more dangerous is the 440 volt 3 phase power you will need to operate the 1500 watt 10 foot long CO2 laser that is melting said aluminum.

Syp

[tintruder]

watzmann,

what do you want to cut?

There are several sources for CO2 lasers 50W-150W for under $1000 (kit-style...you will be messing with power supplies, optics etc.)

These will cut thinner materials at moderate speeds.

There are materials CO2 will not cut. Copper, for instance. You'd need a UV laser for making circuit boards.

Obviously, a lot depends upon the wavelength of the laser, so if you list what you want to cut, I'm sure you'll get pointed in the right direction.

As a note, there are lots of "medical" lasers you can pick up cheaply, and since many of them are delivered via fiber-optic, if what you want to cut falls in with their capabilities, it's pretty easy to run the fiber optic cable out to the "spindle".

Tom

[rolandf]

Syp

I'm glad you find my post ammusing. The danger is not from the molten aluminum rather from a high power laser beam that is now being reflectedted into random directions instead of cutting your material. Any beam that is powerful enough to cut through material can generally cut through you. My only point was that the laser wavelength needs to matched to the material you plan to cut so that the radiation is absorbed and not reflected. A reflected high power beam IS more dangerous than a confined high current power supply.

[Syp]

No CO2 laser delivers through fiber optic. Very few materials will pass the CO2 wavelength efficiently, because it is so long (almost far IR, like a heat ray). The medical lasers use a system of mirrors in an articulated arm (up to 9 mirrors in certain arms) to bounce the beam back and forth down to a handpiece which has the focusing lens. These arms can be used as-is by mounting a lens to the z axis of a mill and using the arm to deliver the beam to the lens, or you could take apart the arm and build a flying optic type of laser engraver/cutter. For some reason, a lot of the arms I have taken apart have had their mirrors cleaned with like a brillo pad and spit, because the mirrors are in bad shape. I guess the medical tech guys don't know squat about how to clean optics (optic grade methanol and lint free optical towelettes). Note that you lose about 5 watts or so in the arm optics, more than that if the mirrors are dirty.

Still, the medical lasers are a great source of parts, and you can usually get them almost free from hospitals and companies that deal in used hospital gear (they actually get paid to haul these lasers to the dump when the hospital decides to scrap perfectly good units). At worst case, pull out the triodes, filament transformers and sockets and sell em to ham guys on ebay for mucho $$$$.

Syp

[Syp]

Hey Roland, it was not your safety post I found amusing, but rather the fact that 99% of these guys will be dealing with a sub 100 watt CO2 laser, which would look at the alluminum and run the other direction instead of melting it. You need to be very carefull around a CO2 laser beam, but there are a few things that make it one of the safer lasers to use.

1) The 10,600nm wavelength is blocked by common items like glass and clear plastic, making laser protective eyeware available at home depot for $2.99

2) A focused beam that is reflected from a shiny surface such as bright copper or alluminum (which you should not be trying to cut anyway, because as I said, the laser is going to run howling in the other direction) will be diverging rapidly. By the time it gets several feet from the focus spot, the beam intensity is way down, and *probably* will be absorbed by safety shields or worst case the plastic goggles you should be wearing. Still, it is best, like you said, to know what material you are cutting and how it will react to the laser beam.

The worst problem is that cutting certain materials will produce very toxic gasses, such as cyanide from kevlar, that you will NOT want to breath.

Syp

[CNCadmin]

I'm off to build my second co2 laser machine. This time I'm installing a beam expander and the table is much larger. My table is enclosed in plexi glass and I use and high volume vacuum to suck the smoke out which it produces a lot of.