Mike wrote “Strange that there is no indicator…” Yes, that baffled me when I found it and I had no idea that it was a permutation/combination lock until I got it home. You are right, tolerances are low.
In operation there are up to 14 turns on the crank one way until it hits a stop and you can feel it when it picks up each tumbler–more so now when it is as dirty as it is–probably much less so when I clean it up. I had first assumed that the flat spring pushed the bar or “locking dog” as the patent puts it, out of the way as the tumblers lined up, and there would probably not be a click or noise at all. Or the spring could only be there for friction so the tumblers do not slop around as the others are turned. I will need to investigate the spring position more fully. At the time I just shook the broken pieces out and simply noted that they were deep in the mechanism. If the lock is oriented one way, then gravity would drop the “locking dog” and a spring for this purpose is not necessary at all. I will eventually clean it up and refit the spring to see how it feels when it works.
It is a much different perspective when you are looking at a lock in terms of manipulation as an escape artist might. Thanks for that insight Mike.
I have written to the historical society of Irwin Pa. but as yet no reply.
