[JackW]

Hi,

I'm mostly interested in Gruen watches and have recently taken the jump in to actually servicing the watches that I buy. In the first two of the three cleaning and oiling 'jobs' I've performed (can I call this an overhaul?), I got the stud back into the balance cock without too much fuss. Movement #3 went down hill and I ended damaging the staff. :roll:

The hair spring stud. It is a vexing little POS.

The way I'm doing this is that I place the balance complete and staff assembly on the top plate jewel and get the end of the staff set. I then place the balance cock on top and get the other end of the staff set into the jewel. Then using my tweezers I try to get the stud to line up with the hole and 'wiggle' it in. What are others doing? Should I try to attach the spring stud first then try to assemble the whole thing into the bottom plate?

Tips and suggestions are most welcome.

 

[Archer]

Have you tried laying the balance cock upside down on the bench, and placing the balance on and feeding the stud through? This way you can line up the stud and also the balance spring in the regulator pins, then tighten the stud screw, flip it over and install it on the movement. Depending on the watch this can be a bit easier than trying to coax the stud into place while it's all on the movement.

Cheers, Al

 

[Paleotime]

Have you tried laying the balance cock upside down on the bench, and placing the balance on and feeding the stud through? This way you can line up the stud and also the balance spring in the regulator pins, then tighten the stud screw, flip it over and install it on the movement.

This is how I go about it. It is possible with a round stud to rotate it accidentally and deform the hairspin. This hasn't ever caused any damage in my experience but it will prevent the movement from running. Just make sure the hairspring coils are concentric when you tighten the stud, or you get to do it again.

BTW, it is still possible to slip off the stud and mangle a hairspin but this is also quite possible with the other method too.

 

[Henry Hatem]

Generally speaking the technique is to place the oiled balanced cock upside down make sure the balance spring stud screw is adequately backed out and with regulating pins opened place the sprung balance upside down into the balance cock jewel. When you are proficient you will have a very high rate of success getting the balance spring stud into it's hole. The stud is then tightened using the screw. The balance is then picked up and gently turned over above the bench as to let the balance hang from the cock. After the balance is in the movement check that the balance spring is in the regulating pins and adjust the height of the balance spring by loosening the screw and using a CIMP to set the balance spring flat. Cleanliness and lubrication rules apply.

 

[JackW]

Great! I appreciate the insights you guys are offering. One question: I was advised awhile ago, that I should not let the hair spring support the weight of the balance wheel. Apparently, Gruen Hair spring are soft. It was suggested to use tweezers to hold both the assembled balance cock and balance assembly together to place it right side up onto the movement. Well, the advise was on the removal of the assemble, so I had figured that it should be true in reverse too.

Another question: What is a CIMP?

for additional reading, I cross posted this at the Gruen Forum, where I have gotten at least one response.

 

[Henry Hatem]

Balance springs can support the weight of the balance. Be careful and deliberate with your movements and use a balance tack. On older watches the steel wasn't as hard or elastic. So being softer requires more care - any stretching can distort the spring out of flat - but - the balance spring can support he balance. A wildly bouncing spring can of course distort or tangle - be careful and deliberate and use a balance tack (yes I repeated myself). I think the "don't let it hang" is somewhat of a tale in that it provides a safe approach to the unskilled. I am speaking of relatively modern watches here not boars hair or glass etc......

The CIMP is my un-patented but copy righted "Carl Issacson Memorial Pick" Do a search and you will find the info - it is a DIY pick for delicate manipulations.

 

[JackW]

Thanks you.
Found what you are talking about here. Although the picture is gone, it is well described and making new tools is a fun part of this hobby. Especially if it is one that seems helpful on different levels.