If you deside to build a laser cutter in general and a CO2 laser cutter in special you have to consider that you must take precautions to not hurt yourself or others with direct or reflected laser light. Where the light of a diode laser is mostly visible, that of a CO2 laser isn’t! Furthermore the power of a CO2 laser is much higher. After this build you come in the adjusting period, then you have to work with an unshielded laser beam in order to line up and direct the beam to the right spot.


Where laser light, direct or even reflected, in the visible spectrum can destroy your retina, the laser light of a CO2 laser can destroy your cornea. That is not very pleasant!

So please be very very carefull and allway be aware of what you are doing!

One other thing to be aware of is the power supply needed to drive a CO2 laser tube. These power supplies can kill you! The one for this build wich can drive a 40W tube, has an output voltage between 15 and 25kV! Even if the machine is switched off, you have to wait a while before handling the HV-cables, because it takes some time fort the power supply to fully discharge! Wait at least an hour and then test it with an isolated srewdriver with the metal part connected to earth!

The power supply and the HV cable going to the laser tube must be shielded with grounded shielding. Further on in this instructable you can see how I did this!

The toxic fumes coming from the lasered materials has to be discharged to outside your home or building. You can do that with a motorised air vent and hose, trough a window or wall, or, as I did, with a hose connected to a central mechanical air exhaust system of my home.

And to make all the misery complete: DON’T LET THIS MACHINE WORK UNATTENDED! I mean really don’t! Do not leave the room while the cutter is cutting or engaving! It can catch fire! And allways keep something at hand to distinguish a starting fire instantly!


In this build I have as safety precautions: a 5mm thick polycarbonate window to safely look trough at the working laser, a emergengy kill switch wich totally disconect all the mains power lines, a normal and a key switch to switch the HV on or off and microswitches on doors to switch off HV when opening, thus the normal and key switch has to be in the on position and all doors has to be closed to let the laser work!


If you are new with laser cutters/engravers it is advisable to read more of this topics on the internet, specially the CO2 types where you can familiarise yourself with the do’s and dont’s!

Well if this all isn’t discouraging you and you build a thing like this, you will be rewarded with a great tool to make beautifull things!

But first of all: BE SAFE!

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