BALL-HAMILTON MAINSPRING

[Phil Weaver]

HELP!
Could someone please tell me what the proper mainspring is for a Ball-Hamilton
model 999, size 18 pocket watch?
--THANKS
PHIL

[Phil Weaver]

HELP!
Could someone please tell me what the proper mainspring is for a Ball-Hamilton
model 999, size 18 pocket watch?
--THANKS
PHIL

[doug sinclair]

Hi Phil,

Depending on the number of jewels your Ball has, there could be variations in the strength of mainspring that you require, but the hook, length, and width should be the same as the Hamilton springs listed below.

If it is 19 jewels, use a Hamilton 944 spring

If it is 21 jewel, use a 940, 941, 942 or 943 Hamilton spring.

If it is 23 jewels (lucky you, that's a rare one) use a Hamilton 946 spring.

Quite often, the higher jewel count watches used a slightly thinner (weaker) mainspring.In a pinch the 940 series spring should do for any one of the jewel counts.

You material supplier should be able to supply you the correct spring with this information since all of the parts for these Ball 999 numbered models interchange with the Hamilton numbered equivalent. It is surprising that some material suppliers do not know that Ball grade 999 watches (16 & 18 size) were made by Hamilton. Hope this helps.

Regards,
Doug Sinclair
Calgary, Alberta
Canada
83914

[mrmel]

What is the size ??x??x?? for the Hamilton 940 mainspring?