Pendulum Suspension Spring needed

[David99]

Hi, I have a Dumoulin Neuf aH Molle mantle clock stamped 858, I'm looking for a replacement pendulum suspension spring to replace the one that has broken. The one I have measures (A dim) 5.12mm wide by (B dim) 24.83mm to ~25.07 length (estimate), with two side by side lengths of suspension spring (C dim) ~9.73mm long (estimate) (1.45mm wide x ~0.03mm thick).

Which one do you recommend?

 

[demoman3955]

I just bought a bunch like yours from Ronell clocks and i like their site because they gave all the measurements of them. The bad thing is there are so many to look at. I didnt even have a good sample, and still found one that worked.

 

[tracerjack]

The important measurements are spring thickness, total distance from hole in the upper block to the pin in the lower block, and the width and shape of the upper block. Since yours looks to have standard square/rectangular blocks, spring thickness and total distance from hole to pin are the most important. Since you have these measurements, you must look through pages of suspension springs at suppliers like Timesavers, until you find one that matches. Slight differences can usually be tolerated by the movement, needing only to adjust the rating nut for time keeping. The blocks can be slightly shorter in height, as long as the distance from hole to pin is correct. Or, you can take the pieces to a clock repair person who will either have the correct one or can order it for you.

 

[Dick Feldman]

David,
Check this link: Timesavers
You may need something like P/N 11068.
Many times those suspension springs will have to be modified (the cut out on the top block) to clear the adjusting mechanism.
Once you have a suspension spring that you are comfortable with, you will have to adjust the beat on the clock. Check out this link for that process:
https://mb.nawcc.org/wiki/Encyclopedia-Subjects/Clock-Repair/Beat-Setting-101
The most important dimension for timekeeping is length, hole to pin or hole to hole.
Best of luck,
Dick

 

[David99]

Thank you to all who responded.
I am learning quite a lot from all of you as I go through your posts and your input has been a great help.
Due to a few other issues, suck as cracks in the fame discovered via a more through inspection, significate repairs to the frame would be required. Although repairable, soldering the frame, and a few other things I found during the inspection, we decided that we will not perform the repairs to this clock at this time.