I'm just going through my "to fix" drawer and for some reason I picked up my 16s Model 1860 Waltham to look at a little bit closer. It has a broken staff (both pivots). I have a new staff for it that is supposed to fit the 1860 model KW 16s, BUT, the new staff and the broken staff aren't even close to the same overall length. The new one is shorter than the broken one. The new one appears to be the same as the broken one in looks, it's just shorter. I can't drop the new staff into the movement to check the overall length because the pivots need reduced in size to fit the jewels. I'd need some kind of drive dog for my pivoting tool and I have no idea what I could use other than buying one of the dog sets which are a bit spendy. It's possible the broken staff isn't correct. It's also possible that NEITHER staff is correct. Most of the staffs for Waltham 16s movements are around 5.35mm but there's no info for the Mod 1860 KW staff that I can find. The broken staff with no pivots is 4.92mm and I added on some extra for pivots to end up with something around 4.97mm or so. The new staff is only 4.87mm. So, now I'm wondering how someone would measure for overall staff length from the movement. The only way I can think of is to pull the cap jewel off the balance bridge and run a wire down through the hole jewels to rest on the lower cap jewel. Bend the wire at the top of the upper hole jewel, clip it off a little bit long and trim until the wire is flush with the top of the upper hole jewel. That's a lot of fussy microscope work for not much result. Plus it'd be easy for me to screw up or break something else. Anyone have a better idea?