A lot of people asked me about additional information about my laser cutter project.
The Laser Driver, is based on the A 1 MHz Analog Laser Modulator Based On LM317 Regulator. I planned to build a Laser PCB Exposer like this one. But after some calculations I was not longer convinced that it would provide satisfying results in resolution and usability. I canceled the project and the laser with driver was unused for more than a year.
However, the driver has some serious disadvantages for this use case.
First of all, if the Atmega (Arduino) is booting up, all pins are high-Z - this is enough to power the laser, not on full current but it is damned bright. I highly recommend to build another driver from Sam's page. The analog modulation is not necessary, neither is the switching time.
Secondly, a current monitoring by the Arduino would be nice maybe even current controlling. I think this is worth to invest some time in.
Thirdly, no emergency switch-off or at least a second enable pin.
The Laser itself is a 445nm Diode I've purchased for about 50€. It was labeled 1000mW, but I don't believe it will run this long on that power output.
Now to the mechanical part. I don't feel comfortable by releasing the complete design because I'm not happy with it. It was very quickly done and has a lot of disadvantages. The worst part is the swinging of the Y-axis.
I think, a possible solution is a second belt, but this increases the cost and complexity of the device.
I used Skeinforge to generate the G-Code.
I added a M103 to turn off the laser and a M101 for turning it on. So you have to add these two commands in the Commands.cpp file of the firmware:
I hope some of you found parts of this entry useful.