Cutting circuit boards?

[Niklas Bjornestal]

Does anyone know if its possible (and safe) to cut circuit boards with the laser?

[Rob Young]

Depends on your setup. Go over to www.lpkfusa.com (http://www.lpkfusa.com) and look at their laser equipment. It is ment for exactly that job. I think it is used more for flex circuit board material (polyimide) than rigid fiberglass (FR-4, G10) but with enough power you can cut the FR4 and certainly ablade the copper.

[James Stokes]

I have tried to cut it with my 100 watt laser with no sucess.

[Martin Reynolds]

Yes, phenolic materials burn rather than cut. Lots of smoke and occcasional flame, dirty burnt incomplete cuts. Very slow, very hot. The polyimide material should cut well, but the copper will probably be too much.

[Dan Hintz]

Not with the hobby-/semi-professional-level lasers most of us use. The resin and fiber strands in FR-4 make it pretty much useless to try and cut with the sub-100W units. A typical 64 mil PCB could be cut with a 100W laser at a rate of 1ips with the use of Nitrogen as the air assist gas, but you're not going to be too happy with the cut... heavy char, ragged edge, etc.

[Richard Rumancik]

I have cut bare FR4 1/32" (about .032") and it worked, but the edges were black and charred. In my case I was able to sand off the residue. I doubt if I could do much thicker with a 30 watt.

I also tried Kapton polyimide film and it did not work. It created a lot of black charring and buckled the Kapton film. If you look at the LPKF lasers for Kapton, they are not normal CO2 lasers. The lasers we use have a wavelength of 10.6 microns. The LPKF lasers, although they are CO2 lasers, have a wavelength of around 9.4 microns. CO2 lasers have a couple excitation levels and they use lasers designed for the lower wavelength. Apparently it makes all the difference . . .

As far as cutting copper: copper is difficult even for machine-shop lasers due to refectivity. I doubt you can even get through .001" of copper with (say) a 50 watt machine.

[Niklas Bjornestal]

I have tried it now.
I was able to cut through 1.5 mm (about 1/16") with my 25W (30W real output) Mercury but with alot of flames and smoke. It might be possible to increase the speed or lower the ppi to get a better result with less flames.

[Michael Simpson Virgina]

I found the best way to cut Circuit boards using reasonable equipment is a Band saw with a bi metal blade.

I have cut thousands that way. Nice edge and very fast.