Does anyone know the proper balance staff number for a waltham 18s 15j HC sn8412107??

Thanks...Mark

Hi Mark,

This is a Model 1883 Grade 820, my parts book lists a waltham staff #1365 should be the correct one. Please be aware that there is three or four different pivot sizes for this model.

hope this helps.
Bila

Bila...Thanks for the info from down under,Appreciate you finding that for me,the Swigart book wasn't much help...since I am a newbie how does everyone determine pivot size? even if you have a caliper what if both pivots are broken off the existing staff??Best Regards,Mark

Hi Mark,

If both pivots are broken off I would measure the jewel hole size, I have a set of Swartchild tools for measuring the jewel while still in the plate. Otherwise you would have to remove the jewel if you have something like a Coates Jewel Gauge or similar. I have not been into this long so someone else on the forum might be able to enlighten us further.

Cheers,
Bila

Without the use of fancy tools you could use a small smoothing broach. Carefully pass the broach through the hole until it fits snug. Mark this position with your thumbnail pull it out and measure the diameter of the broach at your nail with calipers.

Regards, John

I "believe" there are two staffs for the 1883 model, the #1364 and #1365.