40khz vs 120khz or 40 plus 120khz US cleaning?

@george53,

So long as it's a DC motor, and the power supply that is provided with it will state that, reducing voltage is a way to reduce motor speed.  Problems come up with high load/torque applications where the low voltage can draw a lot current and potentially damage the motor or overload the power supply such as some pumps.  But the spinner is very low load/torque, so I have never heard of anyone damaging the motor so long as sufficiently large power supply is used.  

@antinn 

Provided wall wart for motor only shows input voltage/amps.  Box for motor states DC motor, so I’ll go with that.   Hey great I feel good about this.  There’s no heat provided with this unit so I can at least slow it down.  Thanks for EVERYONE’s input on ultrasonic cleaning.  

My VPI 16.5 gave out. I removed all the parts and made a new box out of 7 layer plywood. The old particle board started to disintegrate and it was leaking. I should be back up and running this weekend.