Best place for hard stops?

[Robin Hewitt]

Before fitting hard stops, calculate the maximum force you are looking to handle.

eg: 3Nm on to 5mm pitch = 0.378 tons

Then make sure your soft stops are good

[magicniner]

If you envisage that the likelyhood of a nasty crash is high then supply your stepper PSU through a cut-off circuit with switches at the ends of travel, if you use a multi-pole, double throw relay you can E-Stop your spindle controller and E-stop your control software at the same time.
No matter how kind your hard stops are if your machine winds into them hard you're no better of than if you hadn't fitted them at all,
- Nick

[mitchejc]

Thanks for the advice gents. I like the idea of avoiding running into any hard stops by using additional switches to disable the drivers or cut the power to the drivers and I'll look into that a bit more. I wanted a foolproof way in case something goes wrong and I run thru my limit switches and these additional switches you suggest will do exactly that.