Beats per minute

[Craigmile]

Hi, my first request from sunny South Africa.
Anyone know the beats per minute / hour for a Swiza Cal 8 ? I cleaned and re oiled but cannot get it running fast enough. Adjuster at stop point, and didn't want to move hair spring securing point

 

[Willie X]

Did the balance hairspring go in the US?
If so, thars yer problem. You now have an etched (weakened) hairspring. Willie X

 

[Craigmile]

Did the balance hairspring go in the US?
If so, thars yer problem. You now have an etched (weakened) hairspring. Willie X

Thanks, presume "etched" meant to be "stretched"?

 

[gmorse]

Hi Craigmile,

presume "etched" meant to be "stretched"?

No, I'm sure Willie meant what he wrote; if the surface of a spring like this is in any way compromised, it has an effect on the strength of it. A spring's strength is directly proportional to its width, inversely proportional to its length, and proportional to the cube of its thickness, so any damage to the surface of such a thin piece of steel has a greater effect.

Regards,

Graham

 

[Craigmile]

Hi Craigmile,


No, I'm sure Willie meant what he wrote; if the surface of a spring like this is in any way compromised, it has an effect on the strength of it. A spring's strength is directly proportional to its width, inversely proportional to its length, and proportional to the cube of its thickness, so any damage to the surface of such a thin piece of steel has a greater effect.

Regards,

Graham

Thanks all, got it sorted now. Many thanks