Hello:
I purchased a non-working New Haven clock yesterday at the ESR. It is a small octagon oak gallery type clock with a balance wheel escapement. It has two mainsprings for the time. The hairspring needs to be replaced. Can someone tell me?
1) How I can determine what type of hairspring I need. Is it as simple as measuring the inside diameter of the collet?
2) Where I might find on of these little guys?
Thank you in advance!
Grant

Hello Grant, Bruce Forman has an ad in the services section of the MART. He does work with hairsprings, but I don't know for sure if he can help you with your particular problem. If not, perhaps he can give you a lead. Nice meeting you at the ESR. Mike C.

Grant,
Perhaps you could elaborate on what is wrong with the hairspring that came with the clock.
If it is still there, measure the thickness and width, like you would a mainspring.
Try to find one close (you can get an alarm clock hairspring from supply houses).
I have also used the hairspring off of the hermle replacement for the floating balance.
Start with the longest length if you don't know what it should be. Shorten it (at the stud) don't cut it...
The width can be wider to compensate for a thinner hairspring and vice versa.
A lot of times you may come across a clock that has no hairspring and no reference to go by. It then becomes a trial and error method.
In extreme circumstances where I cannot come up with the proper hairspring (usually too weak), I put in 2 alarm clock hairsprings and the comination will work out with some trials.

Hi James, good ideas on the hair spring problems.
I know i will work on and encounter some problems some day.
Enjoy the site.