Bi-fold door top slider - 4" long for 3/4" rail

The top sliding carriage in my bi-fold door failed, so once again I had to decide between hunting for hours in stores for a replacement part, or design and print one in 30 minutes. I chose the later and designed a carriage suitable for 3d printing: for example the clips are mounted on compliant blades to give them better elasticity than the original. I've reused the springs from the original Stanley carriage, but in theory the springs could be 3D printed too (maybe next version :) ).

So far seems to work really well, I'll improve the design after the 1st failure (likely friction wear in the clips)

Prints without supports (but you have to cut the 4 tiny built-in supports post-print).

The included model is for 102mm (4") long carriage and fits rails that are 18mm wide (3/4") and 12mm internal (1/2"). I've also included the original OpenSCAD source in case anyone needs it for different rail or spring sizes.