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HAMILTON 950 Missing Serial Number

David Nelson

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Apr 21, 2010
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Has anyone come across or heard of a 950 Hamilton with no serial number? I have not taken it apart yet to check plates and balance cock for a number but there is no number at all visible . The usual place is just blank.
 

Larry Treiman

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Jan 18, 2009
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What do you mean by the "usual place"?

The "usual place" on a Hamilton "bridge model" such as the 950 is on the under-side of the pillar plate, where it should be visible from the back of the movement down in the recess between the barrel bridge and the balance cock.

Larry Treiman
 

terry hall

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Procured one a few years ago from Art Zimmerla a 950B with no serial number, Art obtained directly from Hamilton.

Purchased at mid-winter Florida regional when it was located in Orlando... if that helps to date it.
Resides now in a collection about 40-50 miles from me.
I believe in a 'madeup' model 17 skeleton case unless my recollection is wrong.
I thought I may have a pic, but the pic may not have survived 2015 crash.

Larry is of course correct, serial if there will be visible between bridges and will have a "S" or a "2B" prefix.
no other bridges will have serialization.... maybe the balance

If a 950 or 950E, i would expect all bridges to be serialized...
 

Larry Treiman

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[EXCERPT]Larry is of course correct, serial if there will be visible between bridges and will have a "S" or a "2B" prefix.
no other bridges will have serialization.... maybe the balance

If a 950 or 950E, i would expect all bridges to be serialized...

Hi Terry,

David said he had a 950, NOT a 950B or 950E. Neither the 950 nor the 950 E would have a letter prefix to their serial number, so I wouldn't have said that!! They were numbered with serial numbers in the non-prefixed numbers used for earlier Hamiltons. The 950B was numbered in its own serial number sequence, most of which had an S prefix.

Since you mentioned it, the 2B serial number sequence was intended for a 23-jewel Ball Watch Company model, a Ball version of the 950B, to be designated 998B, and numbered 2B 001 through 2B 800 but the Ball order was cancelled before any watches were completed.
.
Serial numbers 2B 001 - 2B 700 were completed as standard Ball 999B, 21-jewel movements, which would have been otherwise numbered with a 1B prefix. The remaining 100 movements in the Ball order, 2B 701-800 were finished as Hamilton 950B movements and were the only ones with other than a S prefix.

There was no need to mention the letter prefixes since they didn't apply to David's 950. However, since they were mentioned, I thought I had better offer an explanation to prevent any confusions for readers of this thread.

Actually, I hate having to explain what I didn't say, but it is sometimes necessary in order to prevent confusion and to eschew obfuscation! <];>)

Larry Treiman
 
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terry hall

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yesir Larry, you are correct in regards to 950 and 950e lacking any prefix to the serial number.
Sorry if i caused some confusion there... and yep 2b711 resides here... and I've observed some S prefix apparently finished as 992B instead of 950B just to throw anudder wrench in the works :)
 

Rhett Lucke

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Has anyone come across or heard of a 950 Hamilton with no serial number? I have not taken it apart yet to check plates and balance cock for a number but there is no number at all visible . The usual place is just blank.
I would be interested in seeing pictures of the subject watch and hearing if you find any serial numbers on the pillar plate or back of any other plates.

As Terry mentioned previously, Art Zimmerla found a couple 950B's, as well as 992B's and 999B's in the engineering vault without serial numbers. These watches were reportedly associated with a decision that was made (and quickly reversed) to remove serial numbers from these watches as they were no longer required for manufacturing purposes. The realization that these serial numbers were required by repairman and railroad watch inspectors was likely the reason for the decision not to go through with the change. A copy of the engineering memo, reversing the decision has been seen.

In regards to your watch, I've seen a number of 950's as well as other grades without serial numbers. A few of these were documented to have come out of the engineering department and were likely prototype, production sample or test watches of some type. I've also wondered if some of these could also have been used for assembly or other factory training. It's also possible that some unmarked plates made it out of the factory and were assembled outside of Hamilton (i.e. lunchbox specials).
 

David Nelson

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Apr 21, 2010
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Hi.
There is no serial number where it should be. No number anywhere visible. I am very familiar where it should be as I have owned a few over time. I plan on removing the balance and the bridges tonight to look there. I will try and post some pictures.
 

Larry Treiman

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Jan 18, 2009
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Your hairspring does not appear to be the Swiss-sourced Elinvar, which Hamilton used during the 1930s, and which was dyed blue to cover up a rather ugly, uneven buff-color in its natural state resulting from the heat-treating process. Rather (if my eyes aren't deceiving me), it appears to be the new and greatly improved alloy that Hamilton first introduced c.1940 on their all-new grade 992B and dubbed "Elinvar Extra". The new Elinvar Extra is easily differentiated from the earlier Swiss blue colored "Elinvar" alloy by its mirror-like, white metallic color.

The main problem with the original "Elinvar" was that it was softer than the steel hairsprings used previously, resulting in more sluggish balance motion, and it was more easily distorted and damaged during normal handling by watchmakers; when you are working on Elinvar watches BE EXTRA CAREFUL!!!

Hamilton had been searching during the 1930s for an alloy that could replace the rather problematic Elinvar, developed by Ch. Ed. Guillaume, for which Hamilton had an exclusive license from the Swiss for American use. They finally found it at International Nickel Company in the form of NiSpan-C. This time Hamilton got an exclusive license to manufacture the alloy in their own factory and use it for horological purposes, mainly as "Elinvar Extra" hairsprings.

David, I noticed that the portion of the 2-piece barrel bridge that carries the crown wheel has the last five digits (49895) of a serial number that fits into the last run of 950 E movements, from 1940-41. Note that the damaskeening pattern on that bridge matches that of the 950E, and does not match that of your 950.

Also, the "heel" of the balance cock appears to be numbered 2118, The latest run of 950s that I could find that 2118 could fit into would be 1652001 - 1653000 from 1924-1925-1926, though I could have missed a later one while squinting at the small print!

The plot thickens; I'll leave the fun of solving the mystery to you and others!

Larry Treiman
 
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John Cote

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David,

Does this watch have any provenance/history that you know of which might lead to some conclusions about...well...how it came to be? Is it just a pawnshop find?
 

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