Nice write-up! Thank you… I have a Model 395, Type 4, and pretty sure I have a switch problem… Took the unit apart and cleaned with alcohol, but no change… The tool ramps up to speed (seemingly correctly) until I reach about 3-to-3-1/2 on the switch. It then levels-off at that same speed through the “4” setting, and then completely quits at 4-1/2-to-5 setting on the switch… It does that every time.. So the 3-1/2 speed setting is about as fast as it goes…

This familiar to anyone else? Again, pretty well convinced it’s a switch issue, but just thought I’d post to see if anyone else has experienced this, and the solution… Thanks!