mainspring installation: double bridal with hook

[LittleWatchShop]

Is there a trick to installing a mainspring with a double bridle and hook? DBH. Example: Elgin 539.

I did it, but it was not pretty.

Edited September 25, 2022 by LittleWatchShop

[RedVitus]

There are some tips I've learned that make it easier - still takes 2 or 3 tries each time (or more).

They cant be installed from the ring AFAIK.  I let the spring out into a "parts barrel", since the tab will scratch the bottom. Then I remove the usual way before winding.

This is the way I learned - leave the bridle out of the drum plus a little bit extra when winding. Line up the tab piece with the slot in the barrel, then hold in place with screwdriver (in between the tab and the winder) before depressing the button.

It's the same procedure for the t end springs and the springs without a hole. The hole should line up right if the tab is in the correct spot. 

 

[JohnR725]

1 hour ago, RedVitus said:

This is the way I learned - leave the bridle out of the drum plus a little bit extra when winding. Line up the tab piece with the slot in the barrel, then hold in place with screwdriver (in between the tab and the winder) before depressing the button.

It's the same procedure for the t end springs and the springs without a hole. The hole should line up right if the tab is in the correct spot. 

with anything that has a protruding T type end they cannot be inserted from the ring they come in they will never ever catch. The only way is to use a mainspring winder as described above. 

then in addition to the largest screwdriver you have the hold it in place you can also use the end of your tweezers just something to hold it in place when pushing it out as a heck of a lot of force.

 

https://www.watchrepairtalk.com/topic/7137-placing-a-t-end-mainspring-back-in-the-barrel-how-to-line-the-t-up/