Prusa i3 Z-shaft end stopper

The Z-axis shafts on my acrylic frame Prusa i3 had to tendency to creep upwards as my prints progressed to the point where they would dislocate themselves from the bottom hole in the frame. After checking everything I could think of to fix the issue with no luck, I made this little add-on.

The shafts protrude from the top by 3mm so I made the captive hole 3.2mm deep, you may need to adjust this to suit if you have the same issue (or tell me how you fixed it in the first place, LOL)

The par