08/31/2026
I spent some time this weekend figuring out exactly how the k***s on the rear pop-out windows of my 1966 Volkswagen Beetle are supposed to work. The k**b screws onto the threaded portion of the window latch assembly, but there's also a tiny set screw in the side of the k**b. What confused me was how that screw could do anything without preventing the k**b from turning.
The answer is pretty clever. The set screw isn't tightened against the threaded portion of the shaft. Once the k**b is screwed into position, the set screw is tightened just enough so that its tip extends underneath the threaded portion of the assembly. The k**b can still rotate normally on the threads, but when you try to unscrew it completely, the set screw catches below the threaded section and prevents the k**b from moving far enough upward to come off. In other words, it's a retaining screw, not a locking screw.
That also explained what was going on with my Beetle: both of those little set screws are missing. The k***s still work, but without the screws there's nothing to prevent them from eventually being unscrewed completely and coming off the latch assemblies. One actually came off and that's what led me to find out what was going on. I've now ordered replacement set screws so I can put them back the way Volkswagen designed them.
It's a remarkably simple little piece of engineering—and one of those tiny details on a 1966 Beetle that you might never understand until you actually take the time to figure out how it works.
