Noisy X and Y Motors

[cstorer]

Just thought I'd pass this on as I have not seen anything like it on the forum. A couple of days ago the X motors and Y motor on our ShopBot started making a chatter as they were moved. Our school has a PRS Alpha ShopBot. We have a laptop computer next to it that is used primarily for the ShopBot. I dropped the X motors and made sure that the gears were good, were tight, and that the carriage was tracking correctly. Everything seemed good. When I ran the motors in the dropped position both were chattering. When I ran the Y motor...it also chattered. I spent several hours tightening and re-positioning the motors and gears with no changes to the chatter. After several hours I noticed that the power cord had become unplugged to the laptop computer. I plugged it back in and started testing the motors again and incredibly discovered that the chatter had disappeared. I unplugged the laptop and tried again....the chatter started up again........plugged it back in....and the chatter disappeared. I am at a loss why this is but would be interested to find out.

[adrianm]

Probably the Power Plan the laptop is using when on batteries (check in the control panel power settings) is affecting the CPU and/or USB causing communication slowdown.

I know a lot of people use laptops on their CNC's without problems but personally I would always opt for a "proper" PC as laptops have all sorts of power saving features that cause issues like this.

[bleeth]

Don't ever try to run the bot from a laptop on batteries. Com is slowed down.
I second Adrian.