Quote Originally Posted by Soyb View Post
I have the option of using mechanical switches that have enough travel to react in time to a crash / runaway so I will use them but have a play with the proximity switches to learn how they work, every day is a school day!
Proximity switches are much better, even the cheap ones, than mechanical switches unless you buy expensive high-quality mechanical switches.
They react faster and are more reliable, a long time ago I did a test showing the repeatability of the cheap proximity switches to show how repeatable they are, it's on youtube and this forum somewhere. But since that time I have literally fit 1000's to machines I build and I have very few issues, probably 2-3 in every 100 will arrive faulty and I rarely have any fail when in use on the machine, I can't remember the last time I had one fail on a machine.
However, everyone I've fit slides by the target rather than face on. They sense and repeat just fine when sliding past the target and you don't risk crunching them if crashing the machine at high feeds where inertia will cause overtravel even though the switch reacted quick enough.