Odd behaviour from a Venus 188

[Delroyb]

Just servicing this Venus 188 from a Breitling 1190. Balance was OK but the hair spring shot to bits. I've replaced the hair spring with a spare I had. All appears to be well, but this is the behaviour I'm getting on the timergraph. https://youtu.be/ylBTMAq9RHc

What could be causing this. Everything appears to be in order.

[Delroyb]

 

Edited May 12, 2017 by Delroyb
video not placed correctly

[Delroyb]

So, is this too much oil on the pallets?

Edited May 12, 2017 by Delroyb

[StuartBaker104]

Its hard to tell from the video, but it looks as though the escape wheel is occasionally skipping past the other pallet stone. Could be a chipped stone damaged tooth on the escape wheel or bent pivot on either...

[clockboy]

I would say it is a mile out of beat. Check the balance jewel visually to make sure it is in the middle of the banking pins.

[Delroyb]

Right, an update on this. Last night and this morning, I did the following. 1: Fulled pallet fork, cleaned and re-oiled stones (with a lot less oil. 2: Stripped the balance and reset the hair spring so the impulse jewel is definitely in the centre of the banking pins.

No change at all. Stil beyond erratic.

Next stop is a check of the escape wheel, fortunately I have a few spare 188s so will see how we get on there. Thanks for the suggestions all.

[clockboy]

Looking at the vids I would say it not the escape or escape area. Something is slowing the watch possibly a bent pivot.As I stated in previous posts it only takes the smallest of faults to stop, slow or cause erratic behaviour


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[Marc]

I would remove the balance and inspect the drop and the run to banking on each tooth of the escape wheel, moving the pallet manually using a dry oiler. It may be that the pallet stones and/or the banking pins are out of whack (although these faults might be expected to manifest more consistently), or that there is damage to some of the escape teeth. It would at least be a good idea to be confident that each tooth on the escape wheel is engaging, locking and releasing consistently and correctly in order to rule out escape wheel / pallet issues. It might also be worth checking the guard pin and safety roller. If all these are ok then it looks like something is intermittently fouling the balance wheel causing it to occasionally rebound before it has reached its natural reversing point. In fact it might be worth just checking that first.

[Delroyb]

Thanks Marc, I will continue my investigations via process of elminiation. All good experience!

[VWatchie]

On 5/13/2017 at 10:16 PM, Delroyb said:

Thanks Marc, I will continue my investigations via process of elminiation. All good experience!

I know it's been a long time, but do you remember if you found the source of the problem and if you found a solution? Thanks!