Record 170

[StuartBaker104]

Would appreciate some thoughts.

I've been working on a record 170 movement which I've cleaned, reassembled and oiled, but it has an odd timing fault.

Dial up and dial down I get 305 degrees amplitude, but when the movement is on side (crown up, down, left or right) the amplitude drops to about 255 and it runs about 2 mins a day slower.

I've tried recleaning and oiling the balance jewels (not shock protected), and I've had a good look at the balance staff under a microscope and don't see any signs of wear or dirt on it. There is no sign that the hairspring is touch anything in any position, and none of the train wheels or pallet staff have exessive side shake.

Does anyone have any good ideas for how to troubleshoot this?

Thanks in advance!

S

[frenchie]

random thought: the balance is true, correct?

[StuartBaker104]

Yes, looks pretty much perfect.

Going to check the pallet fork pivots, and then probably strip the train down and re-clean it later tonight.