how many Limit Switches do I need, is 3 enough 1 on each X Y and Z. ? Also do #i need a certain type of wire Sorry but I'm not great on electronics Thanks
One each for homing (so the machine knows where it is). Two each for limits (so the machine doesn't crash into the ends). You can do homing + "soft limits", where you tell grbl how big the machine travels are, and it refuses to run g-code that goes outside of that volume. Works pretty well, I'm sure many people run that way. Technically you can of course run without homing, limits, and/or soft limits, but you have to be very careful what you tell the machine to do and how you turn it on and off. Wires should be shielded, ferrited and ideally capacitor-filtered.
Get https://openbuildspartstore.com/xtension-limit-switch-kit/ - onboard RC filters and LED indicators (; Also has a pullup on the signal line so pretty resilient against noise, they were made for our typical setups!
