While examining a staff removed from an old model 1857 Waltham, I was somewhat surprised to find that .67mm was missing. For an 18s staff with a broken pivot, I was expecting something around .30mm.

Examination with a 30x pocket microscope revealed what appeared to be a hole drilled in the end of the staff. If the hole could be drilled deep enough, could a new pivot be inserted?

Compared to the new staff, the old one appears to have been turned by a watchmaker. If this were true, then why turn a .67mm long pivot that is only .16mm wide? It wouldn't take much of shock to snap a pivot like that!

Could someone have turned a new pivot with what was left of the staff and then bend the balance cock down? If so, wouldn't the roller table rub against the pallet fork?

The new staff hasn't been fit tested yet. The new staff pivots need to be reduced from .18mm to .16mm and my Levin balance chuck won't accept anything larger than .14mm. I may have to chuck the staff in a collet, find another balance chuck or buy a Dorrington pivot polisher.

Has anyone experienced a staff with such a long pivot as this one?

John D. Duvall
Vice President, Education

John,

It could have been either scenerio... extra long repivot or bending of the balance bridge.

I have has a few of these model 57's and have seen both fixes. One of the problems with this model is that there wasn't stringent standardization of parts yet. The Model 57 had many developments from different balances, potances, hairspringing, beats, etc. An excellent cronology can be found at Ron Price's online resource

Ron Price's Orgins of the Model 57 page

When watchmakers were given these things to fix, they often had to make due with available resources. Given all of this, working on these is almost like working on swiss craft industry stuff, and that usually means having to turn a custom staff.

Mike Miller

Mike,

Thanks! BTW, did you get my email about the staff dimensions?

John D. Duvall
Vice President, Education

Hi John,

Yes I received your email. Been a long day. I'd like to take you up on that offer if it still stands.

Mike Miller
NAWCC Member# 154831
NAWCC-IHC Charter Member# 27

Heartland Horology

Based upon what I see in the images above.........

I'd say the old staff is hand made (and not very well). I'd also say that sometime afterwards, the lower pivot was replaced, and the replacement pivot is now missing. Furthermore, it appears as though the upper pivot may have been replaced in a similar manner, although it's really tough to tell for sure.

It amazes me that someone still has a new staff for an undersprung Waltham 1857. Most of those were depleted prior to the start of the 20th century, and a NOS one is probably a lot more rare than the watch it's going to complete! As evidenced by the fact that a watchmaker in the past found it necessary to make a new staff by hand, and then another watchmaker found it necessary to repair the existing staff at least once, it's fairly obvious that staffs of that sort have not been readily available.

For what it's worth, the simplicity of the design of the #279 staff is probably not an accident. They were probably designed that way to (A) keep machine processes as simple as possible for manufacture, and (B) to make replication as simple as possible when necessary for repair.

A while back, I checked into getting a relatively obscure staff reproduced on a limited production basis. S. LaRose has/had a contact in Switzerland who will do that, but the minimum order is 1,000 pieces. Needless to say, no one wants to have their capital invested in something that would take years to sell, and that's why only staffs for common models are commonly reproduced.

In all the years I've been repairing watches, I can only remember having to restaff two or three 1857 Walthams, and I had to make the staffs for those.

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Steve Maddox
Past President, NAWCC Chapter #62
North Little Rock, Arkansas
IHC Charter Member 49

Steve,

Thanks for looking at this one. I thought the cuts looked quite odd on this one.

Are most staffs manufactured today done with computer controlled lathes?

John D. Duvall
Vice President, Education

Sorry for the delay, John -- I failed to re-check this topic after my last reply!

I really don't know how staffs are produced now in watch factories, but since large quantities of exactly the same dimensions are required, I'd say the old mechanical "screw machine" type lathes that were used a hundred years ago, are probably still being used today for that purpose. Once one is set up to produce a particular pattern, it should do that as well as anything else.



So how did the 1857 turn out? Did the new staff require a lot custom "fitting," as I would expect, or did you get lucky and everything work out? What sort of "fun" did you have trying to poise the three-spoke steel wheel, and what sort of positional rates did it produce when finished?

Just curious..........

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SM

Steve,

Thanks for the info. I haven't gotten around to replacing the staff yet. My Levin balance chucks would only handle pivots up to about .14mm. The 1857 staff that Brian C. donated has pivots that are around .18. Brian was kind enough to loan me his balance chuck that will handle the larger pivots. All I need to do now is reduce the pivots to approx .16mm. I was going to do that Sunday night but I wrenched my back just before leaving for church trying to catch the new puppy. So it was just the preacher and me doing most of the standing during the service. I can only set for a few minutes at time and there's just no way to set at the bench and do any delicate work. I’m hoping my back muscles don’t spasm anymore and can get back to the watch by the middle of the week.

To top it all off, Sunday was my birthday!

John D. Duvall
Vice President, Education

I sympathize with your back problems..... My back isn't too great either, and sitting at the bench for 14 or 16 hours a day certainly doesn't help it.

In any event, I hope you feel better soon!

================

SM

John, just want to say:

Thanks Steve and thanks Carlos for the wonderful card!

John D. Duvall
Vice President, Education