Gaurd pin rubbing on safety roller -Timex

[Neverenoughwatches]

Hi watch folk ...having returned to some watch repair after a long break, i am back with a little Timex that is having amplitude issues and low power reserve. I dont expect much from a pin lever but performance is not enough yet to justify putting it on someone's wrist, a day and a bit of run time would be acceptable. I think I've narrowed it down to rubbing of the gaurd pin on the safety roller. There is safety clearance when moved but the gaurd will rub in most instances. I'm fairly sure this is due to excess side shake in the lever  ....the v-Conic balance has almost none, so the roller is stable, but the lever bearings do have wear. Should I be looking for any other reasons besides this ?  Tia.

[RichardHarris123]

Sort the side shake on the lever and see what happens. Take it from there.

[Neverenoughwatches]

9 minutes ago, RichardHarris123 said:

Sort the side shake on the lever and see what happens. Take it from there.

That's not an easy fix Rich, the train and escapement are plate bearings. I think closing the lever bearings might be a bad move, they have a deep narrow sink as do all the train bearings. Fitting friction jewels might be possible but again a big ask in something this basic. I thought about shaving the gaurd pin down so it has a little more clearance but still holds the escape teeth lock. 

[nevenbekriev]

Sorry Rich, I have missed this thread .

Pin lever escapement is a special one. It is simple, but often simple things has more complex action and action explanation than the complicated ones.

I need some photos or at least to know if there are banking pins or no.

The movement of the pallet fork after unlocking can be separated to two parts: First part is obligatory movement, caused by pushing one of the pins by impulse plane of one of the EW tooth. Then the next, second  part of the movement is 'run to the banking', which is generally caused by the 'draw'. As we have discussed before, the draw is like attraction the fork to the banking pins if like they are magnets. The draw is good thing, but it's presence in pin pallet movement is much more problematic to ensure due friction and the design and it is much more reliable on one of the sides than on the other. Small wear of the teeth where the pin drops on rest plane will kill the draw. Do You have reliable draw on both sides? But I know the answer...

Now about depth adjustment and the things the depth affects...

Increasing the depth will increase the limits of the obligatory movement of the fork. This is good, as if You increase this limits, then probably the guard finger will stay more away from the safety roller, in both sides. So, even if there is no reliable draw, this can solve the problem. BUT, in movements where no banking pins, increasing the depth will decrease 'run to the banking' and the limits of the entire movement of the pallet fork (just like closing the banking pins in regular movement), thus bringing closer the guard finger to the roller.

If the distance the guard finger stays to/from the roller is different on both sides, it is simply corrected by bending the fork. Generally, adjustment of worn pin pallet escapement is question of compromise between all the needed conditions to ensure normal work. But it is not good idea to shorten the guard finger. The worn bearing holes of the pallet fork and escape wheel make the compromise hard, sometimes impossible, so it is good idea to restore the holes, may by closing by punching and then broaching or by rebushing. In worst cases, EW teeth reshaping helps. But this are cheap movements, so  one usually will do it only for fun...

 

 

[Neverenoughwatches]

2 hours ago, nevenbekriev said:

Sorry Rich, I have missed this thread .

Pin lever escapement is a special one. It is simple, but often simple things has more complex action and action explanation than the complicated ones.

I need some photos or at least to know if there are banking pins or no.

The movement of the pallet fork after unlocking can be separated to two parts: First part is obligatory movement, caused by pushing one of the pins by impulse plane of one of the EW tooth. Then the next, second  part of the movement is 'run to the banking', which is generally caused by the 'draw'. As we have discussed before, the draw is like attraction the fork to the banking pins if like they are magnets. The draw is good thing, but it's presence in pin pallet movement is much more problematic to ensure due friction and the design and it is much more reliable on one of the sides than on the other. Small wear of the teeth where the pin drops on rest plane will kill the draw. Do You have reliable draw on both sides? But I know the answer...

Now about depth adjustment and the things the depth affects...

Increasing the depth will increase the limits of the obligatory movement of the fork. This is good, as if You increase this limits, then probably the guard finger will stay more away from the safety roller, in both sides. So, even if there is no reliable draw, this can solve the problem. BUT, in movements where no banking pins, increasing the depth will decrease 'run to the banking' and the limits of the entire movement of the pallet fork (just like closing the banking pins in regular movement), thus bringing closer the guard finger to the roller.

If the distance the guard finger stays to/from the roller is different on both sides, it is simply corrected by bending the fork. Generally, adjustment of worn pin pallet escapement is question of compromise between all the needed conditions to ensure normal work. But it is not good idea to shorten the guard finger. The worn bearing holes of the pallet fork and escape wheel make the compromise hard, sometimes impossible, so it is good idea to restore the holes, may by closing by punching and then broaching or by rebushing. In worst cases, EW teeth reshaping helps. But this are cheap movements, so  one usually will do it only for fun...

 

 

Thanks Nev, I will answer in order of questions, there are no banking pins with this movement.  The draw...no draw on one side but maybe a very small amount on the other. The gaurd shake was a little more on one and looking at the finger did have a slight bend which I corrected a few days ago. But also has a rough burr on one side of the tip, I did think of a compromise instead of reducing the finger, shape a slight curve to each side at the tip so IF it touches the roller the contact area is to a minimum and also polish the tip to minimise any friction. I wondered if it was posiible to increase the lever pull.... run to banking by changing the draw angle...adding a shape to the lever pins. I assume one of the reasons for poor draw with pin levers is the contact angle of a round pin, that becomes worse after wear.

But yes mostly for fun, my wife and daughter both love Disney , my daughter is covered in Disney tattoos and I thought this old 40s Mickey Mouse watch would make a nice restored keepsake from a crazy dad that tinkered with watches when I'm gone

[nevenbekriev]

Hi Rich, this is not rare thing for pin lever to have no draw and guard finger to touch the roller but to work well enough. The roller... It is usualiy part of the staff and is polished, also with small diameter. And, adding some small quantity of oil there also helps. But what is the condition of the staff pivots tips? I mean, the free oscillations test count DU and DD? As this is the main reason in such movement for bad amplitude.

[Neverenoughwatches]

11 minutes ago, nevenbekriev said:

Hi Rich, this is not rare thing for pin lever to have no draw and guard finger to touch the roller but to work well enough. The roller... It is usualiy part of the staff and is polished, also with small diameter. And, adding some small quantity of oil there also helps. But what is the condition of the staff pivots tips? I mean, the free oscillations test count DU and DD? As this is the main reason in such movement for bad amplitude.

Thanks Nev, now that i have the lever removed I can test for oscillation counts. Yes the roller is part of the staff but quite rough in appearance, not so much polished.  The v conic pivots look a little rounded as well. So I have a couple of things to improve here.