Please help: spindle dropping when attaching Dust Shoe

[Jimmy Phillips]

On my PRSAlpha BT48 while the controller is on and when I attempt to slide the the dust shoe on the spindle carriage, it will drop from the additional weight (I am guessing), and thereby lose the Z-axis position within SB3. I then have to re-zero the Z axis. I would think with the springs and stepper energized it should not drop like that?

Thoughts anyone?

Thanks, Jimmy

[khaos]

Check the set screws are tight in the drive gear.

[phil_o]

Contact Shopbot directly for technical support. You may to upgrade the springs. I had a similar problem, SHopbot sent be new springs.

Phil

[Jimmy Phillips]

Thank you. Will do.

[MaxFrenzy]

On my PRSAlpha BT48 while the controller is on and when I attempt to slide the the dust shoe on the spindle carriage, it will drop from the additional weight (I am guessing), and thereby lose the Z-axis position within SB3. I then have to re-zero the Z axis. I would think with the springs and stepper energized it should not drop like that?

Thoughts anyone?

Thanks, Jimmy

This definitely shouldn't be happening. Turn on your system, make sure the Z motor is powered/energized and with your hand, see what kind of force is required to break that axis loose. Pay attention to the sound you hear. You'll know if you're fighting against the motor. At idle, the holding torque is going to be essentially the best it's going to be, and that should be really difficult to do by hand (e.g. you'd really need to yank down on it). Checking set screws is a good idea. Make sure the spindle is mounted tightly. While your at it, check your v-rollers are snugged up appropriately. You shouldn't be able to move the Z car (not spindle) front/back or left/right. Those Z springs are essentially just keeping the spindle from bottoming out on your table when the machine is off.