Hamilton 992 help

[chaplin37]

I'm servicing a Hamilton 992 and it is running slow in the dial down position and I've tried everything and I'm stumped. Look at it under the microscope. I have cleaned and oiled it multiple times, no cracked jewels, no worn holes,nothing is rubbing or touching anything, hairspring is flat, mainspring is correct and new, no dirt or old oil, wheels are not bent or broken, nothing wrong with pivots. Runs fine in all other positions. I'm lost at this point.

[JohnR725]

 

I'm servicing a Hamilton 992 and it is running slow in the dial down position and I've tried everything and I'm stumped. Look at it under the microscope. I have cleaned and oiled it multiple times, no cracked jewels, no worn holes,nothing is rubbing or touching anything, hairspring is flat, mainspring is correct and new, no dirt or old oil, wheels are not bent or broken, nothing wrong with pivots. Runs fine in all other positions. I'm lost at this point.

This is a place where a timing machine would be nice you didn't mention if you used a timing machine? Then very nice if the timing machine can measure amplitude. So timing difference between dial up and down with a timing machine you will usually see a amplitude difference. that will tell you that there's a difference between the ends of the pivots. Then what is your definition of too slow?

[matabog]

All the pivots and jewels on the dial side should be checked. Also the axial shake off all the train wheels and the pallet fork.

[matabog]

Imho you lose power dial down.

If this is not the case, then also check the hairspring between the regulator pins, dial down. Also the regulator pins should be paralel and straight.