Selecting a suitable laser toolhead

There are two basic traits I look for when hunting for a commercially available toolhead: optical power and required input power. Optical power tells me how strong the laser is and whether it can cut through the materials I am planning to use in as few passes as possible. The strongest toolhead I dare use at home is a unit with 15W of optical power. These days, you can purchase toolheads with 20W or more of optical power. These are mostly diode lasers that use one or more diodes to achieve the rated cutting power. When I first started out, a typical toolhead had a single diode for the beam. Today, you can purchase a toolhead that features a combiner that merges the beams of multiple diodes to increase power. This way, diodes that can generate 5W each can generate 15W or 20W combined for excellent cutting power.

Remember that we are talking about a laser head that we are adding to a machine here. There are machines you can buy online that are already...