Laser module recommendations for DIY projects


I’m building a small laser machine for myself out of parts from an old 3D printer. Currently I’m looking at laser modules to use there - something like this looks ideal, but I’m weary as the price seems a bit low for such a high power laser.

I’d like to know what sort of stuff to look out for when choosing a laser diode. Currently I want to use this machine for:

  • vaporising spray paint from circuit board blanks, or exposing photoresist on either dry film or photoresist blanks
  • cutting thin sheets of plastic <= 1mm
  • engraving (but probably not cutting) wood and plastics


You can’t use a diode, you need a laser tube and mirrors

@tombull has a warehouse of knowledge here

The folks at Endurance Lasers would beg to differ, although they charge much higher prices for theirs :wink:

You can absolutely use a diode instead of a tube (i.e. gas laser) and mirrors - or any of the other many ways of producing a laser (doped fibre, solid state laser, semiconductor lasers, etc). The key things are: 1. being able to focus the laser on to your material and 2. your material being opaque at the wavelength of the laser you’re using. Generally for visible-light lasers (most diode lasers), most material that isn’t transparent or reflective to the eye will work. In terms of focussing the beam, most diode lasers also come with a lens that is appropriate to focus the beam over a fairly useful depth of field. So, yeah all that really matters is the power you get out of the laser - which will determine how fast / well you can engrave or cut various materials.

About that… there’s a lot of specification exaggeration going on with laser diodes. Often a ‘10W’ Chinese laser might actually output <2W in usage. Fortunately, equipment exists to measure the actual light output power of laser diodes. I’ve been scouring the internet for about half an hour to see if I could find a list of measured laser diode powers - I’ve defintiely seen one before, maybe on a laser pointer forum. But I can’t find where the hell it is. Anyway, more reputable suppliers will give a more accurate account of the actual power their diodes produce. Expect to pay around £100 from a cheap Chinese supplier for a diode that can actually produce 4-5W - which is a good amount for a decent, if fairly slow, laser engraver like you’re describing. Cutting through darker shades of acrylic up to a couple of mm thick will be possible too. For the same power from a reputable supplier who has actually measured the power, it might be £250+. Unfortunately, I have no idea what power the particular laser you’ve linked might actually produce.