Threaded saddles…

[T70]

I have a few vintage bridges here that I’m trying to match to the appropriate guitars for restoration.

Some bridges have coarse threads on the low E, moving to fine threads at the high E. However some have consistent threads across the saddles (more coarse than fine).

Is there a rule of thumb for when Fender used which style?

[bulrich]

Up until late 61 JM bridges were all wide thread. During late 61 to early 62 you see the bridge thimbles go flush with the body (to make room for the Jaquar mute). You also see the 2 saddles for the plain strings high E, B go to a fine thread.
Of course this wasn’t always consistent and as it goes with these bridges, things were often changed, swapped or flipped.

[T70]

Up until late 61 JM bridges were all wide thread. During late 61 to early 62 you see the bridge thimbles go flush with the body (to make room for the Jaquar mute). You also see the 2 saddles for the plain strings high E, B go to a fine thread.
Of course this wasn’t always consistent and as it goes with these bridges, things were often changed, swapped or flipped.

Thank you! This info is hard to find.

[JSett]

Thank you! This info is hard to find.

Not in this offset nerd-hole

[Highnumbers]

Up until late 61 JM bridges were all wide thread. During late 61 to early 62 you see the bridge thimbles go flush with the body (to make room for the Jaquar mute). You also see the 2 saddles for the plain strings high E, B go to a fine thread.
Of course this wasn’t always consistent and as it goes with these bridges, things were often changed, swapped or flipped.

Nice forensics!

I can confirm that at least by Q1 of 1962 the bridges had a mix of wide and narrow threaded saddles. I have two '62 Jazzmasters (March and June), both of which have the mixed thread saddles and smaller bridge thimbles.