A belated thanks for your reply Overloaded.
In truth I don't have a clue what kind of switch is being used. They are simply the ones that came stock on the MaxNC lathe. I suspect that they are not the snap action type as they don't make an audible click when operated manually as well as not behaving as you describe - i.e., they are very sensitive near home and can yield a home location that vaires a couple of hundreths
. It seems to me they are likely simple push switches.
As for the debounce, the XML file provided by MaxNC has the debounce set to 2000. Since there is no obvious shielding on any of the stepper, encoder or switch wiring, I suspect that noise is a general problem.
As is certainly readily apparent, I am a rank novice at all of this and have my hands full just figuring out the mechanical and software aspects of this art. If anyone has any recommendations for replacement switches, I'd be grateful. The machine is set up to accept 1/4" diameter axial switches.