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Posted (edited)

I'm working on a Hamilton 917 and while testing the functions after reassembly I noticed that the escapement is showing a fault.

 

While checking the pallet operation on the escape wheel, I noticed that about 3-4 times per revolution the pallet fork will not snap over to the entry side banking pin. Usually when I check the locking and unlocking of the pallet, the pallet will snap from banking pin to banking pin with just the slightest touch of the tweezers. This pallet (Only on the Exit Stone) with release the escape wheel, but not snap over to the other banking pin. The escape tooth entering the pallet hits the entry stone on the face and forces the pallet back to the exit side banking pin without first locking on the entry pallet stone.

 

To narrow this down to the pallet and not the escape wheel, I swapped out the escape wheel and the same thing happens.

 

I swapped out the pallet with another and the problem disappears. So I'm confident that the pallet is at fault, but I'm not sure which pallet stone to adjust. I'm thinking the exit stone should be pulled out a bit, but I'm not 100% sure....

 

Any ideas on what I should do?

Thanks!

Edited by DJW
Posted

Hi Don, are you able to do a couple of close ups. One with the exit pallet locked and one with the entry pallet locked.

Posted

I really tried but all I have is my phone! It's just not working... I can say that it does appear that the escape teeth are hitting a lot shallower on the entry stone as opposed to the exit stone, quite a bit actually. Maybe a little more than half as much? Does that make sense?

 

So maybe the entry stone is not out far enough to catch the tooth?

 

BTW, I installed the balance and it seems to run quite well regardless!

 

I'm getting 300+ amplitude in every position (I did install a new mainspring).

Posted

Try it on one third wind - if it is stopping then you need to remedy the pallets, possibly by adjusting the lock.

 

 

If you are getting a nice 30 hours out of it on a full wind and it's keeping time, then I would not go to the trouble. 300 is a good amp. This is why I like the timing software from Graham Baxter (Google it) as you can leave it running all night and then check the graphs in the morning and see what gremlins you can find :)

 

 

Posted

Thanks for the direction Mark! I'll work on it tonight some more. I'll post what I find...

Posted

OK, so I checked the watch on just 2-3 winds and it runs fine and does not stop.  Although it really bugs me that I know there maybe something out of adjustment, I guess I won't worry about it. I'll check it in the morning to see how it's running.

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