Fixing Pearl if the Z is stuck at the bottom

Pearl has had some incidents recently where the Z was “stuck” at the bottom. This isn’t actually a mechanical jam, it happens if the prior user jogs the Z axis all the way to the bottom limit and powers it off there. Upon power-up, the controller sees a limit switch already tripped and wrongly assumes it’s the upper limit and locks out the “jog up” button so it can’t be moved.

First, please make sure you don’t have the Z jogged all the way down to the limit when you shut it down. This most likely occurred while replacing the honeycomb after using the rotary jig, I suppose it’s a bit easier to not monitor for when the Z’s been taken down enough to create enough room for the honeycomb but instead just jog all the way until it stops at the lower limit. That’s still ok to jog to the limit, but just jog at least 1/2" back up any time before powering down and all is good.

Second, if the Z is found stuck all the way down when you power up, this can be corrected at the panel without any mechanical intervention. It is documented on the Wiki at Pearl - Asmbly Wiki
It’s a “hidden” menu item to disable the limit switch so you can jog it off the lower limit switch, and then reenable it.


Thank you for this explanation, Danny!

1 Like