How do you deal with the noise from the spindle pulley?

[david_geng]

Hi,

I got a Syil CNC SX3. The problem is that there is a bit noise from the mill head, which sounds like something loose there, it's not squeezing, not continuous even noise.

I disassembled the head and located the problem between the belt pulley and the motor spindle. I don't know what's in the original SX3 mill, with the Syil SX3, the pulley has been changed to bigger size.

I reckon the cause of the problem goes down to the motor driving circuit, which simply uses the Hall sensor communication for the brushless motor. Such circuit generate big torque pulse somehow. And such torque takes the advantage the tiny gap between the spindle key and the belt pulley to make a kind of knocking noise.

So I wonder if there is any glue like grease can put there? I've tried lithium gre ase and copper grease without big difference.

cheers
David