Denford Software & Machines

the machine was working fine, though it would get 'lost' on longer jobs and lose the z-zero then misbehave.

then it started 'shuddering' moving in the y or x axes on jog.

the other day it got much worse, losing all zeros immediately and unable to run the simplest job. now it cannot even home, slowly sinking in the z axis when home all is pressed.

any help would be appreciated.

The Homing routine for the machine is that the slide moves towards the home switch until it hits it and opens the contact. Once the contact is open it reverses and moves away slowly until the home switch closes again. It then stops and is at home.

It sounds like there is dust trapped between the contacts of the Z home switch. If you vacuum the switch whilst pressing and releasing it it should clear.

In home mode the status of the datum switch is displayed. If any of the datum switches are operated (the contacts are held open) then the axis is shown highlighted in green.

If the switch has dust holding the contacts apart or you have a faulty switch the axis will be displayed. With the guard open and in home mode if you manually press the home buttons you will see the indicators going on and off.

When you get it back up and running it sounds like you need to spray the slides with silicone lubricant. If you spray it at the end of the end it should dry overnight.

that makes sense, thanks so much!

I hit the switch with compressed air while flicking it on and off. that fixed the homing problem.

then i had a student (I"m a high school teacher) vacuum out the machine, blow out all the crevices with compressed air and vacuum it again. then he lubricated the leadscrews and slides according to the manual. we have not been lubricating enough - the manual says daily, which seems excessive. how often would you recommend lubricating?

Would use silicone once a week if getting well used.
Vacuum out daily.

thanks everyone! now we're back to milling microscope-smartphone adaptors.

arrr! the z-axis is acting up again. i think i have a bad microswitch. does anyone know where i can get one in the US? i'm only finding suppliers in the UK

got it! denford was able to help, once i called england.