PLEASE NOTE: I'm really not competing to win the laser, a t-shirt would be fine, thanks.
I saw the competition and thought it would be fun to show off my system.

INTRODUCTION. The general idea of this CO2 laser system is that a beam is directed down to a part for cutting. The part sits on a computer controlled platform which moves the piece around the stationary laser beam. Cutting is acheived by passing the beam through a focusing lens. A focused beam exits through the bottom of a cutting head nozzle. Gas, such as oxygen, is fed into the side of the chamber below the focusing lens. This gas exits the nozzle along with the beam and the laser beam/oxygen combination serves to vaporize the steel for cutting.

Click here to see it cut

One thing that I discovered when making this system is that purchasing the laser was the easy part; many other systems are required to be on-line in order to achieve anything useful with the laser. To give you an idea, this is a comprehensive diagram describing the basic components of a CNC laser cutting system.

This is a picture organizing many of these components around the central control unit and includes other sub components such as the motors, encoders, solenoids and flow sensors.

Assume for now that you have a really great laser, and these main components are handled:

  • Laser head and power supply
  • Optics
  • Control unit
  • CNC table and power supply.
  • Computer
  • Cooling systems

What other systems have to be on-line in order to have a cutting operation?

Two 110VAC 20 amp lines were run to operate ancillary equipment, a 220VAC 20 amp line services the laser power supply, a 220VAC 20 amp line services the chiller outside of my house, and another 110VAC 15 amp line runs room lighting.

It was also useful to make boxes like this that have 110VAC entering into them and also had relays system that could be driven by TTL levels to run various appliances like ventilation.

A ventilation system has yet to be installed in the work area. This will be required to remove fumes and reduce smoke that will contaiminate the optics inside the beam delivery system. The laser has the capability to cut a number of different materials like wood and plastic. Ventilation will be essential to remove the fumes produced by these materials.

Gas Lines
The laser cutting system can use either oxygen or nitrogen depending on the cutting application. This required that a couple tanks get installed and I ended up mounting the tanks up off the wall. This is to conserve floor space so I can cut larger sheets of metal. The brackets came from the welding supplier. The plastic chameleon has a couple magnets embedded in it for sticking to the tank.

Here's a pic of the gas set up. Here is another.

Support Arm
The laser head needs to be suspended about 48 inches away from the nearest wall. Another design criteria was that it has to be able to change the height of the laser along the z-axis. A CAD drawing was put together, and I bought a pile of channel iron, angle iron, and flat stock then went to work with my chopsaw. Note the lag bolts attaching the angle iron to wall and floor.

Here's the support.

Step 1: The Laser Head

This be that laser. My system is based the Coherent G-100, an RF excited sealed industrial C02 pulsed laser. It consists of 100 watt laser resonator and solid state RF amplifier integrated into an all aluminum enclosure. The RF amplifier provides pulsed RF power to the laser to ionize the CO2 gas mixture in the tube. A modulation signal applied to the laser head controls the output pulse width and period. The amplifier produces 3000 watts of RF power.

  • Average power range 10-100 watts.
  • Peak effective power: 250 watts.
  • Input power: 48 volts DC at 50 amps.
  • Weight: 35 pounds.
  • Cooling requirements: 2500 watts, water based.
  • Documentation
  • Original price: $27,000.
  • The Coherent web site.

DC Power Supply. The power supply was specifically designed for the G-100. It is air-cooled and digitally controlled. The supply produces 48VDC at 50 amps and requires 220VAC input.

Control systems. The G-100 has a DB25 connector that supplies control and input modulation signals to the RF amplifier and supplies status information from the amplifier. This allows monitoring of the temperature, duty cycle, and supports digital control of the overall power output of the laser.
hi where can i get this all item for build this?
<p><strong><em>Congratulations</em>, Sir!</strong> Your perseverance is well rewarded.</p><p>Living next to the world's workshop (<strong>China</strong>), in <strong>VietNam</strong>, I opted for the cheaper solution of simply buying our laser cutters BUT you article triggered some D-I-Y thoughts I am going to explore.</p><p>I cannot emphasise safety too much. It is essential to <strong>wear goggles</strong> any time the laser is on as even reflected laser light can gave a deleterious effect on eyes and body! My employees being somewhat lackadaisical weren't using these goggles (<strong><em>only </em>USD$10</strong>) so I fitted very small temperature sensors that are connected to the laser controls to ensure goggles are worn before the power can be applied.</p><p>Your <strong>D-I-Y</strong> surgical endeavours can be prevented by adding two safety buttons, either side of the work space, with protective rings, to prevent cheating the switches, so at least you know where the fingers are!</p><p>We also use CCTV and an closed off area for our workshop, it's amazing the stupidity of some people around dangerous machinery.</p><p>And <strong>OXYGEN</strong>, around oil, can be very dangerous!</p>
<p>I love you! </p>
<p>luv u too</p>
<p>I already have a CNC setup for cutting wood. I would like to add a laser head. Am I right in understanding that the laser you're using in this instructable is $27k? Awesome writeup btw.</p>
I believe the link to &quot;this is a comprehensive diagram&quot; is broken.
where is the laser tube ?
ok, here comes a stupid question., -Why can't you just laser cut by hand-?
The machine would be much more accurate. Besides, how would you wield a 250 Watt Laser with 2500 Watt water coolant?
what if you had it mounted like this but with no motors and used like a bandsaw <br>
I agree, Thanks.
Congratulations, it's a great work and perseverance sample. I would like a CNC of those at home.
This is very cool. The kerf on my machine is 1/8&quot; running a CNC plasma torch. What is the kerf (width of cut) with your laser here?
the secret pro metal cutting laser 150W co2? <br> are the mirrors, lens, polarizer cut quality enhancer, or the collimator, or the laser tube?
Just a little bigger then we will need it in the military. <br />Psssssh Ahhhh wheres my wing!!!
Link near top - &quot;comprehensive diagram&quot; - is 404 Not Found... :-(<br><br>Great project - been thinking about building such a thing (after finding out that TechShop here in the Bay Area doesn't have a metal-capable laser cutter... :-(<br><br>(Hint, hint, Jim, Ridge, et al... &gt;;-)
Lovely project - but expensive.<br>And it doesn't have to be.<br>Less than $350 can get you 3 axes *with* controlling electronics and motors.<br>(see the reprap project for a great example, although with a moving head. a moving table is just as easy and maybe even cheaper though.)<br>You don't even need 3, but if you use 3 you could save on laser power and thus on laser cost a lot by using a reciprocating laser setup which adjusts focus during the cut.<br>A quick look on ebay gives me $1375 (that's with worldwide shipping) for a laser with power supply included.<br>Your transformer setup requires a large, bulky, line frequency transformer which gives you horrible regulation and high cost. A computer power supply or some other form of SMPS will give you much better regulation at a lower cost. The $350 figure already includes the power supply with the electronics though.<br>Cooling with a cheap pump and water is fine, so I'll say $100.<br>I have no clue about optics though, but the optics can't cost a lot more than the laser so I'm making that $1000. <br><br>laser: $6500 - $1375<br>CNC table: $ 500 - $ 350<br>Optics: $2500 - $1000<br>Cooling: $ 500 - $ 100<br>electronics:$5000 - $ 0 (driving electronics included in table price) <br>total: $15000 - $2825<br><br>Savings: $12 175<br><br>Or, if I am wrong about the optics and it's indeed $2500, the total is still only $4 325. Savings $10 675.<br>I hope this is of use to someone =)<br><br>I just realised that the $350 table might be a bit unrealistic for a laser cutter cutting steel sheets - but even a $1000 table still means significant savings.<br><br>Just my $10k ;)<br><br>--Nathan
Hi,<br><br>Do you have any sources to buy Laser Head, Optics..?<br><br>Thanks<br>Yatish
Hi,I am Praful here.I am setting up Laser cutting with Coherent 400W especially for sheet metal.Can you please let me know who can support me for laser head,optics etc.I found 1 laser head frm precitech but its too expensive (20k-Euro).Can you pl give me some inputs rgd this.
dear sir <br>I want to build a cnc laser for cutting stanless steel 6 mm <br>so I need electrical parts . like power suply400w- laser gun-and ets <br>if it is possible for you send me comlete lists of parts and price I.ll need to <br>building these machine. <br> <br>best regards
Really neat and creavtive. Another options, a plasma cutter to save much more money.
I think mr owhite made a mistake the energy density while making the calculations <br>the correct correct is 0.1643 watts/mm2 .
You might update your 'ible with the embedded pics. Apparently the links are dead.
really very nice, great job
dude that is sick awesome!! but way to expensive. its gonna take me forever to gather that much money.
I have a 5KW CO2 laser- when cutting stainless use Nitrogen (99.5% pure) and you'll have clean shiney edges on your steel :), also do you where any eye protection?! I really hope you do, as CO2 lasers emit radition that burns away your eyes lens without you feeling it.
what kind of eye protection do you recommend, would regular safety glasses/sunglasses work or would you need smoething stronger
Regular goggles won't do anything for the laser frequency... you need goggles that are designed just for that purpose... start here...<br/><br/><a rel="nofollow" href="http://cascadelaser.com/safetyeyewear.html">http://cascadelaser.com/safetyeyewear.html</a><br/><br/>Jerry<br/>
CO2 lasers emit a 10.6 micron wave. Regular safety glasses will work fine.
Most safety glasses filter UV. This is IR, 808nm (or 10.6micron, whatever you like).<br>And either way, I wouldn't bet my eyes on a cheap pair of safety glasses.<br>A $100 pair of laser goggles might seem expensive - until you lose your sight.<br>The $50 you saved won't get you back your eye.
808 nm doesn't equal 10.6 microns. That would be 10,600nm which is in the far IR band, and regular lexan blocks it effectively. A few sheets of plexglass would make an adequate enclosure. <br> <br>808 nm, on the other hand is in the visible range and will pass right through anything that visible light passes through.
It is ingenuous to think protection glasses are the definitive solving panacea in protecting your eyes from hundredsW/mm&sup2; and up, reflection fluences.<br><br>It is really important to have the laser cutter inside an enclosure or to precisely study the angles of possible reflections coming out to the observer to create and set protecting panels in the correct paths.<br><br>Most people isn't aware of this and handle lasers with absolutely insufficient care.<br><br>Be aware! You have only two eyes, no spare!
is your laser a diode or a miror laser?
CO2 based laser
Thus, a &quot;mirror&quot; laser.<br>Known to most as a gas laser.
Nice I'ble, but waaaay too expensive for me... Good write-up. But how do you get from 106 watts/in&sup2; to 1550 watts/mm&sup2;? The conversion of 1in&sup2; = 645mm&sup2; is correct, but that would give 164 mW/mm2. Real world check: 100W on a square inch, that's the heat of a strong (old school, non-green ;-) ) light bulb on the area of a bigger stamp. That would be warm, even hot, but not enough to melt steel. 1550W on a square milli-metre? That would be the energy of a bathroom heater on the surface of a ball point tip (give-or-take...). Yes, that might be enough to melt metal. By the way that would mean 1,55kW*645 or about 1MW per square inch!
There's this magical thing called lenses too..
You don't have to melt the steel in order to cut it. The laser ( or torch of say oxy-acetylene or propane-acetylene) only has to heat the surface to the point where the oxygen will start burning the steel which is well below the melting point.<br>The oxidized steel has a melting point of ~ 1450 C and runs off the steel which melts at a little over 1500 C.
the last one is my favorite :D<br /> <br />
What IS the last one anyway?
I believe he/she is referring to the &quot;Items I've Made&quot; section with the last photo being his finger cut by the laser...
Yes, I would have to agree with others. Very, very nice job on the device, but put a metal box around it when it's in use. Cheap insurance against instant blindness...
I think most of the media links on the intro page are broken...
Shame, the video is missing.<br><br>Great blog though, many thanks, Andy
I loved this concept. Would you just clarify the ownership cost?<br>Approximate would do it too.
This really isn't an instructable, but thanks for sharing. This is more like sharing a really complicated project, where no one was meant to follow without extra attention. :)
This is excellent work but pricey for average hobbyists. I think your next project should be an inexpensive CO2 200 watt laser!
&nbsp;Great project but PRICEY!!!!<br /> gotta find a good bank to rob :D<br /> Project is well thought out and&nbsp;<br /> it shows you have put in a lotta effort.<br /> I like but I no makes it!&nbsp;
You could prolly rig a plasma cutter in a similar fashion. The laser is nice and techy but I think plasma will be in the budget range of a few more folks and you can get similar results if you know what your doing.<br />

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Bio: just trying to make sense of this world.
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