Problems with Z-axis if not all axis home

Couse off installation second printhead, moved the Z axis down.
It got down till it didn’t stop.
Problem with this, its has no emg off end switch. This couses the helicoil coupler to tear apart.
Friend of mine also had this problem.
Now its time to design some solution to this problem.

Is there a way, ad a proximity switch or soem kind of end switch to prevent this kind of damage.
On a standard CNC machine, there’s allmost Always a dog, or some kind of protection so that it can’t damage the hardware.
Someone can think with me, to get a solution.
Maybe we can add a falesafe, so that axis can’t be moved further than max 50mm from starting point. That it has to be homed to get the full range!!!
Axis couplers allmost live a lifetime. this one got damaged in less than a month!!

regards Nico

I hate to say this, but that falls under user error. Always home axes before using the printer imho.
That said, you could add a bit of code to the firmware to make it always home before you can move any axes…

Yes that would be a solution…
How can i add that to the sourcecode ??
Anyone have experience with programming this!!!