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

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

Regards

Iyer

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

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.

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

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.

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

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

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.

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

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

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.

Many of the medical lasers you will find today are Nd:YAG. They have a wavelength of around 1054nm, and do use fiber optic light guides. They are typically pulse lasers, and are typically more efficient at cutting metals than CO2, being 1/10th the wavelength. They are rated in KW output, but the beam is short in duration. They will instantly sublimate ANY material you are likely to machine, unless highly reflective. Big fun, but difficult to know if they are working properly when purchased. Also, more maintenance costs on flashlamp pumped units. Modern, continuous wave diode pumped units are spectacular in performance.

Keyence has also released a lazer said to cut metal.

Many medical lasers are indeed Nd:YAG

A few corrections:

1064nm not 1054nm

Most of them are actually CW, in the 100 watt range, though they usually have modes where the laser is pulsed for short times, it is still operating at 100 watts..the pulsing is done mechanically.

There are a class of Nd:YAG lasers that operate with a Q-switch, with many (like 10,000) high power (tens of killowatt) pulses per second. Their average power is actually lower than the CW lasers, perhaps as low as 10 watts. They can engrave metals because the high peak power of the pulses overcomes the reflectivity of the metal and vaporizes it. These are MUCH rarer in the used medical laser field, though there are a few that also are frequency doubled to 532nm green..but the light show guys snap those up.

3) Almost all of them are arc lamp pumped, where the arc lamp is operating continously at an insane amount of power (like 4 killowatts to get 100 watts of laser light). These lamps are actually resting in a high flow stream of distilled water!!! and will blow up instantly if the water flow stops. Also, you have the fun of 100-200V at 30 amps in water..so it needs to be de-ionized, filtered pure water so it does not conduct.

4) The diode pumped "solid state" Nd:Yag lasers use 808nm arrays of little diode chips mounted on heatsinks to pump the side of the laser rod just like the arc lamp did, however they are producing the exact wavelength the rod enjoys...it gets really excited by this wavelength (pun intended). The arc lamp was producing rays all over the place, IR, UV, lots of stuff that turns the rod off. So you use 100-300 watts of laser diodes instead of 3 to 4 killowatts of arc lamp, and you get a nicer beam too, because the rod is not deforming under the intense heat and absorption of light it cannot use (this deformation causes something called thermal lensing, which reduces the beam quality, reducing how well it can be focused on the workpiece).

Please send me any Q-switched diode pumped medical Nd:Yag lasers you have gathering dust in your garage and I will put em to good use ;-)

Syp

Sure you could bolt on a 20 watt co2 laser and cut stuff.... like really really thin paper and such. I wouldn't.

There are some successful attempts with fiber and co2 lasers at 10,6 um! Lord knows when and if they're availiable, though...

Cutting copper or aluminum is easy, all you need is a good laser (TM 00) with preferably 2 - 3 kW of output-power and and a good reflection absorber (lambda-4 mirror)

Actually 20 watts of CO2 laser will cut 1/4 inch balsa, 1/4 inch acrylic, 1/8 hardwood, cloth, thick paper AND really really thin paper :-)

Syp

Syp - If you can cut through 1/8 in hardwood with 20 watts, can you tell me what is the minimum power to cut through one sheet of paper (choose any kind you like ) with a co2 laser ?
I've asked on the forum before, but never got a clear answer.
If you go to my site at www.fanmaker.co.uk you'll see why I only need one sheet cut at a time. I'm assuming also a minimum cut line, say 0.1mm.
Speed can come later - at the moment I just want to gather the info for the minimum config for actually cutting it.

John

Sure...I would say the minimum power to cut through 1 sheet of paper at like 60IPM is about 4 watts with a CO2 laser. I am guessing a little here, but that sounds about right. Or at least I modulate my 15 watt CO2 laser at about 25% and cut paper at that speed. The really cool thing is when you get the power *just* right you can cut out a sticker or label from a sheet and not cut through the backing! I have to turn my dinky little 15 watter down to about 10% modulation for that...

The CO2 wavelength REALLY likes to burn/cut paper and wood..that wavelength is much more absorbed by organic products that the 10x shorter wavelength of yag lasers.

Many thanks Syp.
John

I was doing a bit of CO2 cutting today.
We have a Baasel Lasertechnic CO2 machine (Slow flow external He, N, CO2 gasses mix)which usually runs about 75W at the nozzle in pulsed mode. (200W max) I set it up for CW and tuned it down to 1W.

At 1W I was able to cut through two sheets of 4mil Mylar and a series of other thin "plastics" supplied by a customer who wanted to laser weld the sheets together.

(pretty small window between welding and cutting...would be better to "print" on a UV-activated adhesive and hit it with a UV laser)

So if you need CO2 to cut thin paper, plastic etc, 20W will definately work. My guess is that 5W will do it if focused properly, so SYP is right-on with his estimates.

Co-axial airflow thru nozzle will also help keep down scorching and clear ablative debris from embedding in reflow in meltable materials.

If you intend to be pulsing CO2 for CNC, don't skimp on the power supply.

TOM

tintruder - thanks for the input - would nitrogen(or even co2) be better for reducing scorching ?
Any idea what width cut/beam diameter for your mylar cut ?

Greetings Everyone-

This a topic I may be able to address reasonably well since I design lasers for marking and cutting for a living.

If you're looking to do simple marking or engraving in polymers or anodized aluminum I would suggest going with a small 10-watt diode around 808-nm. You'll need a driver and a small water chiller with a cold plate. I'd suggest looking on E-Bay.

If you're looking for something to engrave or cut wood, you'll need a CO2. These are the easiest to work with in my mind. I'd suggest you look at Sam's Laser FAQs (search Google). I recently purchased a 20-watt CO2 Tube on E-Bay with RF Driver and Power Supply for $100.00US. It's then a simple matter of cooling the unit with water and pump and applying a 0-10VDC analog signal for power level. The Spindle function in MACH3 works well for this.

Christian

give us the nuts and bolts on the mach3 spindle deal. Did you make a board that makes the 5v ttl signal to a 0-10v signal???

Most RF driven CO2 lasers use a 5 volt digital signal, whose duty cycle is varyied to obtain different power outputs. You probably *don't* need a 0-10V signal.

Syp

awsome!
thanks

Hello

http://www.emissiontechnologies.com/plans.htm for a home made laser.

Greg

Not worth it nowadays, unless you just want the educational experience.

sorry wrong thread

Greetings All-

For paper cutting, and even anodized etching (not metal engraving) you may want to look at the Cipher V-10 from Nutfieldtech.com

10-watt CO2.


I've got one and it works great. The only issue I have is that it is a small marking field.

But it includes the Galvos and Scan Lens, is air-cooled and easy to operate.

I added a X-Y stage 14"x14" beneath it to 'shuttle' my large parts around.

The trick of course is making sure the galvos are aligned to the X-Y Travel. Otherwise you wind up with a stitching issue.



0-10VDC. Eariler I posted that I use the 0-10VDC for the analog control. I left something out so I should clarify that now.

I use the same controller for a Ytterbuim fiber laser which looks for 0-10vdc for 0-100% power out.

I run this 0-10VDC signal into a MAX232 chip to convert it to 0-5VDC for the CO2. The MAX232 and MAX233 chips were designed to convert TTL to RS-232 levels (-12<-->12 to 0-5vdc).


Christian

Hi,

What is the price of cipher V-10?

Thank you,

Zoltan

I have a couple of lasers that I have decided not to use. I just listed one on ebay today as I was a little worried about using them. No experiance with this stuff. Now i am wondering if I should this keep one and try and make use it. It is a spectra-physics J20 – BL10 - 106Q. The power supply is a 20 watt fibercoupled q switched supply and the bl10-106Q head is capable of 3 watts average output.

This is where I get confused and can't quite put a frame of reference on the power as output. Three watts does not mena much by itself. Interms of the pulse energy I have these specs.

Pulse width is 10nsec at 10khz
Average power of 3 watts at 30 khz
and pulse energy is 150uJ at 10Khz

I still don't know what it will do at the end of the day. It would be great if some one could give and idea of what this laser is capable of processing.

Thanks all for your comments

It may be that no one knows.
My feeling is that 3 watts is not going to cut much more than a piece of paper.
If you want people to view your posts, keep bumping them every so often so that they appear in the new posts.
Paul

it is a new RFlaser .it is 30W
it is not HVlaser (glass laser)

i have read the post by gbm_design about a new
10 watt co2 laser,
here the link http://nutfieldtech.com

and i would like to expand on the subjet like setting it
up on a cnc machine. It would need probably no mirror
and could be a easy installation.

so if anybody know more about this, let hear you.

I like simplicity. Bob