SDS would not settle down.

[rlw3]

i have a tnt whose sds readout would not settle down (can't be good for the sds lifespan). Thought this was due to my ac quality. Turned out that when I changed from using the spider pully to not using it and going directly to the platter from the motor; the motor was spinning too fast for the sds to compensate. VPI solved this problem by sending me a different motor spindle (the wood piece connected to the motor that the belt goes around). New spindle has smaller diameter so belt now turns slower and within the sds's operating range. New spindle is also same diameter top to bottom which allows a second belt to be used

[Markd51]

Not at all trying to be rude, but this account sounds awful weird.

A wood Pulley? Never heard of VPI supplying a wood pulley to anyone in 17 years.

On my HW-19 SAMA, I have a stepped Delrin Pulley, which can be fine tuned previous to further fine tuning with the SDS.

[rlw3]

maybe the black piece the connects to the motor and the belt goes around is plastic. Important point is sometimes you can wind up with one with too big a diameter, too fast for the sds to operate correctly and it is easy to call and get a smaller one.