Powderless etching means the additive does the work that a powdering machine used to do mechanically. Instead of dusting the plate between passes to protect the side walls, the additive in the bath forms that protection continuously, which makes the process faster, cleaner and far less dependent on operator timing.

That also changes what the machine has to do. It circulates and sprays the etchant at a controlled rate and temperature, and the result depends on the three parts being matched: the plate, the additive and the spray pattern.

Buying the machine from the producer of the plate and the additive removes the integration problem. Where the three come from three suppliers, a poor result is usually blamed on the plate, which is the only part the workshop can see.