Expert: Melvin Mills - 12/11/2008

Question
QUESTION: I recently purchased an Illinois sangamo 21j pocket watch whose serial number dates it at 1901. The dial has hairline cracks and i want to carry the watch for daily use. Will the cracks effect the watches operation? Also, what is the difference between the Bunn and the Sangamo, and are the Sangamo Special and the Bunn Special extremely different in construction from the Bunn and Sangamo? I read somewhere that the early sangamo specials had a diamond jewel on the main mechanism, is that right? Is there a big difference between rubies and saphire jewels for pocket watches? I have noticed that the specials have a different looking gear arrangement than my watch. Any information or history you can give me on my watch and the differences in these other watches would be much appreciated. Thank you for your time.
Josh

ANSWER: Josh,

For starters, no, a hairline crack in the dial will not affect the performance of a watch.  

The following applies only to 16 size movements.

The Sangamo and Sangamo Special were never made in 18 size.
The Sangamo was made in Models 4 and 5 with 21 and 23 jewels. These are also called the Getty Model.

No Bunn or Bunn Special movements were made as Models 4 or 5.

The Sangamo Special was made in 19, 21 and 23 jewel movements, all with individual finger bridges. Some of the earlier examples used diamond endstones over the balance hole jewels. The Bunn and Bunn Special movements used a regular 3/4 plate layout and were made in 17 and 19 jewels (Bunn grade) and 21 and 23 jewels (Bunn Special grade).

The Sangamo Special was considered the highest grade and carried a price premium over the Bunn and Bunn Special when new.
Illinois did lots of odd things over their long history and there are probably some exceptions.

The difference between ruby and sapphire is color only.  
Both are corundum, a 9 on the hardness scale (diamond is a 10). When corundum is red it is called ruby, when it is any other color it is called sapphire.

Kind  regards,

Melvin



---------- FOLLOW-UP ----------

QUESTION: sir, i noticed that the watch gains a few seconds an hour average over several
days, can i adjust this or should i find a qualified person for the job? Is my
watch reliable? thanks
josh

ANSWER: Josh,

Your watch is a high grade watch and, with a proper servicing, will still keep accurate time based on today's standards.  That is not to say as accurate as a quartz watch, but almost as accurate as a mechanical watch.  Certainly good  enough for daily use.

You will not be able to fix this problem because it is much to fast for a quick fix.  

Check to see if it is magnetized.  If you have a boy scout type compass, the kind to determine north, south, east and west, put it on a table.  Next, put the watch next to it and see if the needle moves.  If it does, it is magentized.  Any watchmaker can de-magnetize it for you.  That MIGHT fix it.  

You may want to consider having it serviced anyway if it has been a long time since the last servicing.  It doesn't hurt to make sure the watch is well lubricated.  It will help prevent any future damage.

Kind regards,

Melvin

---------- FOLLOW-UP ----------

QUESTION: sir, i am sorry to take up so much of your time, but my main spring just gave up,
could that have been causing it to be fast? any idea on what it costs to have the
main spring (windable spring) replaced? thanks
josh

Answer
Josh,

No,  the mainspring would not cause the watch to run fast.  

No one will replace the mainspring without servicing the watch.  You wouldn't want that anyway.  

You should really consider having it completely serviced.  One will take the watch apart, clean it, reassemble and time the watch.  

You are probably looking at 100-150 dollars but you will have the peace of mind knowing that the watch will be in good condition.

Kind regards,

Melvin