Jump to content

Helvetia cal 81-24 mainspring check

cduke

By cduke
in Watch Repairs Help & Advice

 Share

Recommended Posts

cduke WRT Addict

cduke

Posted
Posted

Hello Friends

i have a newbie question on checking a mainspring on a Helvetia movement. Without getting to the mainspring, is it possible to determine if the spring is broken? Watch will wind (not run) to full resistance. I assumed that if the spring were broken the watch would wind indefinitely. Is this true?  Getting to the mainspring involves quite some work and I am not sure how to diagnose.

thank you all again for the lessons.

Link to comment
Share on other sites
oldhippy Distinguished Member

oldhippy

Posted
Posted

If you can wind the watch right up, then the mainspring has not broken. if it had broken as you say you would be able to wind it for evermore. Depending on the movement, sometimes you are able to just remove the barrel bridge to access the barrel and replace the spring. Myself I never liked this way because you will dislodge dirt that can get into the train and it will stop the watch. It is always best to do a complete clean.

  • Thanks 2
Link to comment
Share on other sites
Nucejoe Distinguished Member

Nucejoe

Posted
Posted

Hi C     Yes you said it, winds to full resistance. 

Release the reserved power through the click, rewind and  repeat several times, you should get to full wind by same number of smooth turns,  about 20 to 30.

If broken , it turns indefinate as you said or wind some and suddenly discharges the reserved power, depending on the length of broken piece.

 

 

  • Thanks 1
Link to comment
Share on other sites
 Share
Go to topic listing


  • Recently Browsing

    • No registered users viewing this page.

  • Topics

  • Posts

    • Randy55
      Introduction

      By Randy55 · Posted

      Welcome to the group Stirky. You can search for just about every subject in the craft here. Don't be afraid to ask if you can't find the answer that may have already been covered ( some ad nauseum LOL ). You don't have to buy Bergeon to get good quality. There are many decent mid-range tools available that will last you a lifetime. Cousins would be a good place to start . Cheers from across the pond ! Randy
    • Jon
      What are these Seitz B-Jewels?

      By Jon · Posted

      I picked up a similar amount of these jewels some years ago in a watch and clock fair. Every now and then they come in handy. This week I've got a rubbed in bombe jewel in the balance cock that is cracked and needs replacing. Very handy to have a vintage assortment of these type of jewels!
    • Stirky
      Diagram for 6497 motion works

      By Stirky · Posted

      Thanks Jon.
    • Jon
      Diagram for 6497 motion works

      By Jon · Posted

      Great diagram with the teeth and pinion count. Simple way to reduce the speed of the hour wheel by the 12:1 minute wheel. Genius and yet so simple. Always good to reinforce the principal by what you have done in your drawing. Keep doing that. I had a drawing on my wall for years showing me this which is very similar to the drawing you have done. Here's a formula to work out the beats per hour of a watch movement. The movement's BPH is dictated by the wheel teeth and pinion count and the hairspring being vibrated to the correct BPH by finding the pinning up point on the hairspring using a vibrating tool.  The reason in the formula there is X2 on the top line is because there are two pallet stones.
    • DDean
      Incabloc Lyre Spring & Low Earth Orbit

      By DDean · Posted

      So I just wanted to say "thank you" again.  The angle is the key bit it seems and yes, it did basically just fall, or float, back into position when I got it lined up just right. I had meant to add that now that I see how it goes in, I totally see how it came out in the first place, and that whomever cloned the original movement didn't pay much attention to the fine details around the setting or how it interfaces with the balance cock or the "rings" on the regulator and/or stud carrier arms.
×
×
  • Create New...