Q: What's more frustrating than losing one of the darned #K64 pawl springs from a Sturmey Archer hub? A: Finding half of one... :-(
Anyone have a stash? (In fact, what I was working on was a common FW, 4-speed, wide range unit from a '49 Lenton. I had a bit of trouble - still do - with some excess drag in the freewheeling mechanism, so I opened a later ('64) spare, for comparison. That's the one with a broken K64, FWIW. Not sure if it is good news or bad that almost all the parts are identical, but a couple of things had been simplified...)
Q: How many different types of cog-mounts or "drivers" have there been?
A: Well, most of us have seen the the quasi-universal variety with three notches in the body and three matching protrusions in the cogs. Easy change-over with just a spring holding things in place. Before that there was a unit with something like 12 splines and a lock ring. What I found today, I think, on the older FW, was a pure threaded-on cog. Maybe that's the one that allowed building up with a 2- or 3-speed cog assembly for a derailleur assist. I haven't messed with one of those for decades, and don't regret it at all.
Q: If taking apart FW is insanity (as we have discussed), where does that put breaking down SA hubs, and only doing it every few years, so you forget how?
A: On a rationality scale from 1 - 10, about a -5.
Your mileage may vary