Internet Horology Club 185
Hairspring & balance wheel replacment issue

This topic can be found at:
https://ihc185.infopop.cc/eve/forums/a/tpc/f/1086047761/m/7823907197

July 08, 2018, 17:56
Timothy Fitzgerald
Hairspring & balance wheel replacment issue
I have a nice 21-jewel Hampden 18s "Special Railway" movement that had no balance wheel or hairspring when I found it. I'm just getting around to fixing it up. I have always been told to mark where the hairspring was on the wheel when removing it, which I do or photographs.
I got a staff, hairspring,wheel and balance staff how do you set this up so everything is in the correct position for assembly.
Any help would be appreciated
Thanks
July 09, 2018, 10:44
Douglas D. Weaver
Timothy

Since you don't have any previous reference, just go ahead and install the roller table - I usually place the roller jewel perpendicular to the balance arms. In this case, it won't matter which position you choose. Then, poise the balance. Install the hairspring and put the movement in beat.

You didn't mention if the hairspring and balance wheel came from the same movement. If not, you may need to add or remove weight from the balance to get it to keep decent time.

It can be a lot of work, but it's rewarding to bring a quality movement back from the dead.
July 09, 2018, 10:47
Brian C.
Tim,
I would first put the balance on the staff and make sure you have a good free spin. Then I would put the roller table on the staff with the jewel in the center of the balance crossbar. I would then install the hairspring and give the balance turn. When the balance comes to rest, the roller jewel should be in the center of the banking pins. If it's not, turn the hairspring until the balance comes to rest with the roller jewel in the center of the banking pins. When this is done, you can install the pallet. Good luck.
July 10, 2018, 08:34
Timothy Fitzgerald
Thanks everyone for the help.Much appreciated
July 10, 2018, 12:24
Kevin Hoffman
Hi Tim , I would not be too worried , if its wrong just change it , the only thing that matters is where it comes to rest ,the fork needs to be centered , and it will be pretty close , then adjust the hairspring by turning the collet

https://www.youtube.com/watch?v=uvMCNyrDZQo
July 10, 2018, 13:20
Timothy Fitzgerald
Thanks for the video link Smile