Here is a new motor assembly complete with circuit board that is made right onto the thin sheet metal. Black circle is around a scratch I put in board. Looks like the Mfg. just primed the thin steel (I imagine to act as an insulator) then put on layer of copper, light sensitive material, photoetched and wave soldered SMCs and other components. Amazing! Of course there is no price reduction for new style assembly compared to old way of doing things when you buy as replacement part.
Hmmm wonder if you could use this process on thin aluminium?
Y9-02-06
