Chrono hand reset

[Bonefixer]

I think I need to tighten up a chrono hand. When I reset it's overshooting the zero. I'm pretty sure this is happening at the hand/pivot interface rather than inside the movement - if I reset from past 30sec it goes the other way. 
 

can I tighten up the little tube on the hand without ruining it? Would it be a sin to use loctite?

[nickelsilver]

It's rare for it to be internal, that's to say between the arbor and the wheel (though possible in some cases). It's either between the tube and the pivot, or the tube and the hand- and sometimes both.  Loctite is indeed a sin here. You can close the tube either with a fancy Bergeon 3010 tube-closing tool, or, in a collet in the lathe, or, with a small pinvice. You want to go slowly, it's easy to close it too much. If you find that the tube is turning in the hand, you must rivet it a bit more. Here I use a pointed staking tool in the hole, with the bottom of the tube flat on the block of staking tool, couple of light taps, then, a very small concave punch to hit the outside of the protruding tube. It's very easy to bend/crush the tube doing this, be careful!

[praezis]

Rather often I find a crack in the tube (on vintage). Those cannot be tightened, hand or tube must be changed then.

Frank

[AndyGSi]

Photos will help but it's a big NO to any sort of glue.

[Neverenoughwatches]

[Bonefixer]

Pin vice seems to have done the trick - no glue required

 

 thanks for the tips. 

[Nucejoe]

 In general,  If the tube is long enough so you can reach the middle of its length  with a nail clipper, just tighten the midpoint on the tube, you want the tube's free end wider, to facilitate pivot entering in the tube.

 You are likely to tighten the free end of the tube as well if you tighten in a pin vice.

 In case of Chrono hands, there is  usually a flat side inside the tube, which is to face the flat side of pivot, tightening best be spotted over the flat side, bcuz its the  flat side that keeps the tube from over shooting.

Do you fix bones with glue.

 

[Neverenoughwatches]

10 minutes ago, Nucejoe said:

with a nail clipper, just tighten the midpoint on the tube, you want the tube's free end wider, to facilitate pivot entering in the tube.

 You are likely to tighten the free end of the tube as well if you tighten in a pin vice.

Makes sense Joe.

[Bonefixer]

35 minutes ago, Nucejoe said:

 

Do you fix bones with glue.

 

Not generally, but if the bone mass is so weak that a screw won't bite on occasion we do augment the fix with bone cement.