Helvetia cal 81-24 mainspring check

[cduke]

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.

[oldhippy]

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.

[Nucejoe]

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.