Looking through microscope-style eyepieces, the operator can manually direct the parts beneath the beam. Lasers have also become more reliable. Today, it's much better. One of our customers uses both a spot welder and a laser welder on the same line. The spot welder is down much more often than the laser, and there aren't many machines that are simpler than a spot welder.
Most laser welding is done on thin materials.
The maximum part thickness is typically 0.25 inch. The best metals for laser welding have low thermal conductivity and low reflectivity. Nickel, titanium and steel weld better than highly reflective metals, such as aluminum. Resistance welders have difficulty with these metals because their resistance to electricity is very low. Lasers won't work well if the metallurgy isn't good for fusion welding.