Sprinkler for rear window in one of my (actually only) retro cars got broken and lost long time in The Past.
As shooting random people with window cleaner fluid while you try to wipe back window was probably funny as in youtube video, but not really appreciated by people who are personally concerned , i've decided to print replacement nozzle.
It will definitelly fit 3 door version of 1996 VW polo 6n.
It might fit other VW cars about this date (probably up to 2001) like jetta, golf, etc.
v2 uses slightly larger nozzle sizes - pick it if your printer can't print v1 reliably.
v3 - i think final version. it sprinkles where it should, it can be locked securely, and it got improved shape to allow excess fluid to drop from it's bottom tip instead of spoiling VW logo below. Also it got (most) overhangs resolved.
After printing you need to clear interior supports with sharp knife.
also apply a (stainless) nut in the trap - you'll probably need to heat it up to and push it in as the trap is bit fishy in design.
next step is positioning the wiper locking nut.
There are two methods for this - hardware or software :)
for software version (good route if your nut is rust-stubborn to the wiper and you don't want to spoil antique value of your car) you need to open blender file and rotate the 'wiper lock nut' along z axis. this might require change of position of locking parts aswell.
for hardware route
you might need some kind of washer (brass , stainless, teflon) or just a bit of well. Force ;). you need to just place nut in proper position (so when you apply sprinkler it's nozzle is in 'top' position) once nut is in proper position you might try to push the new sprinkler on top of it - it should fit snugly, if not - use hobby knife or small file to make it happen.
test it throughly - it should work even without locking
As sprinkler gives fair amount of pressure, it's good idea to use some sort of glue (like silicone or acryclic) to seal the voids - just don't sprinkle before it fully cures.
ofcourse there is also locknut mechanism to finally secure it to the nut
If anything does not work as you would expect it to (like you get your car fluid sprinkling all over to front window instead of back like it happened with my prototypes ;) - you can tweak the (provided) blender source file.