Elgin balance staff 857, old style vs new style, long hub vs short hub, not sure which I need

[GregG]

I purchased an Elgin grade 288 pocket watch with a broken balance.  After looking up the balance staff number, it is part #857, but there is a footnote to look up what's in the special information section.

Here is a link to that section: https://pocketwatchdatabase.com/guide/company/elgin/catalogs/elgin-watch-co-material-catalog-c.1927/294.

It says for part #857, it comes in four varieties, old or new style with a short or long hub.  It also says a few lines down that the old style was used in most watches with serial numbers below 3,000,000.  My serial number is 12,375,905. 

I also saw this thread, and from the illustrations of the ends of the balance staff (and the attached pictures here), I'm guessing I have either the old style long hub or new style long hub.  Given that my serial number is well above 3,000,000 (meaning I have a new style), and my screenshots match the long hub, is it safe to say I have the new style long hub?

Thanks

Greg

[JohnR725]

On 4/3/2023 at 7:42 PM, GregG said:

I also saw this thread,

seeing as how you posted that link I don't have to post the pictures again. then you did notice that there is a pivots size difference but the staffs not that you're going to have a lot of choice today possibly.

usually when I just do is measure the old staff and then figure out what I have.

Oh and another place to get Elgin part numbers is the site

http://www.elginwatchparts.com/

 

[GregG]

1 hour ago, JohnR725 said:

usually when I just do is measure the old staff and then figure out what I have.

What do I measure if the staff is broken?  I could try to estimate, but the 0.005" difference between the two styles is well within the margin of error for an estimate.

[JohnR725]

On 4/3/2023 at 7:42 PM, GregG said:

is it safe to say I have the new style long hub?

yes you probably do. But no matter what when you remove the old staff and you get your new staff you want to measure all dimensions to make sure they're the same to avoid unpleasant surprises. In other words a new staff for some unknown reason is physically bigger than the old staff you can break things. Or things won't fit and they'll be loose it's nice to know before you try to put it together. Ideally a micrometer works really well here much better than a veneer caliper. Just be careful with a micrometer and the pivots it's easy to damage them. Then for a micrometer you typically want metric because everything in watch repair almost is done in metric.

[GregG]

Thanks.  The upper and lower hole jewel on this particular watch are both cracked, so I want to get replacements for them.  Someone on eBay makes new hole jewels, so I figure I will purchase them, but I need to pick the hole jewel size.  Is the current recommendation for total side shake (both sides combined) ¹⁄₁₀₀ mm or ²⁄₁₀₀ mm?

The pivot size on the replacement is 12, so I'd need to buy either a 13 or 14 size jewel.

Edited April 5, 2023 by GregG

[JohnR725]

10 minutes ago, GregG said:

The upper and lower hole jewel on this particular watch are both cracked, so I want to get replacements for them

then you're lucky according to the parts listing both upper and whole jewels for the balance of the same part number 443

14 minutes ago, GregG said:

so I figure I will purchase them, but I need to know the hole jewel size. 

as the availability of staffs in all different pivot sizes is not what it once was I would find a suitable staff contact the seller of the jewels and ask what size they recommend. Typically the higher the jewel count the smaller the pivot.

 

 

[mbwatch]

On 4/5/2023 at 3:40 PM, JohnR725 said:

Typically the higher the jewel count the smaller the pivot.

Oooh I never knew this, thanks! It will come in handy the next time I'm trying to find a replacement when both pivots are missing and I'm guessing at sizes.