Wiring Limit switches to Leadshine MX3660

[Clive S]

I do not have an automatic tool changer and therefore have to zero the z each time a different bit is used. Zero-ing the z to the spoilboard each time. This effectively changes the amount of travel the z can make. The longer the bit the shorter the travel distance etc. I have approx. 150 mm of travel on the Z.

Yes exactly. So how are you using a Z- limit switch to stop you from diving in to the spoil board?

[malgazz]

It does not prevent one diving into the spoilboard, just limits the amount of damage. I have found that sometimes care is not taken in setting up the toolpath on how the machine zero's on the Z axis. When setting up the material in the cam software, persons sometimes overlook where the Z is zeroing (top of material, or top of the spoilboard).
It is some times confusing to some who are just starting out, that the Z homes reverse to the other axes and incorrectly apply how the machine zero's in their toolpath can inadvertly cause them to cut into the spoilboard.
I sure helped me in the beginning. Subsequently have just left the limit in place, just in case.

[JAZZCNC]

It's just a Spoil board so what's the issue.? Spoil board is meant to cut into it's no big deal.

To Limit the end of travel makes sense if you can run the bearings or ballscrew off the end but just running a little deep into spoil board doesn't warrant limit switches and they can be more trouble than there worth on low end of Z axis.