Seiko oscillating weight - is it possible to reduce play in the bearing?

[mikepilk]

Has anyone managed to reduce the play in the rotor bearing on a Seiko?  This is from a cal 7019

A good tap with a large punch on the lower surface?

[Nucejoe]

 It always a good idea to make sure you have a good bearing before you reduce the play, sometimes I tear the bearing to check all parts, steel balls ought to be checked under microscope. 

Must avoid strong tap or press  as you might create dents on retaining washer. 

REPLACE WITH NEW IF ANY PART LOOKS LESS THAN PERFECT. 

Good luck.

 

[mikepilk]

The bearings aren't available, you have to change the complete weight.

 

[AndyGSi]

If there's play then I'd just replace the complete weight.

[mikepilk]

1 minute ago, AndyGSi said:

If there's play then I'd just replace the complete weight.

I was expecting to do that, but if it's possible to reduce the play, I may as well give it a go

[VWatchie]

10 minutes ago, mikepilk said:

I was expecting to do that, but if it's possible to reduce the play, I may as well give it a go

1 hour ago, mikepilk said:

A good tap with a large punch on the lower surface?

Can you expand on what you mean by "lower surface"? Do you mean to reduce the bearing hole or expand the bearing? This is interesting since you haven't got anything to lose by trying it. Keep us updated, please!

[mikepilk]

31 minutes ago, VWatchie said:

Can you expand on what you mean by "lower surface"? Do you mean to reduce the bearing hole or expand the bearing? This is interesting since you haven't got anything to lose by trying it. Keep us updated, please!

The hole is actually a thread. The slots on top are to screw the bearing on. 

I just found a scrap one from an old 7s26 movement. The bearing is different but similar construction. I'll try to disassemble it ...

Well it came apart 

The are just pushed together. I cannot see any shoulder, so the play just depends on how far the bottom is pushed on. 

Those balls are incredibly small !

Correction - I was forgetting the washer. The top and bottom do push together solidly. There is no more adjustment available. The play is from wear on the sloped edges where the ball bearings run. 

So to answer my own question - no you cannot reduce the play.

Edited August 3 by mikepilk

[AndyGSi]

I would have expected some sort of shoulder as otherwise how do you know the bearings will still roll?

[mikepilk]

18 minutes ago, AndyGSi said:

I would have expected some sort of shoulder as otherwise how do you know the bearings will still roll?

As I wrote in the correction above, the two parts do push together solidly. The balls run in the 'v' shaped gap created by the chamfered ends. It's wear in these chamfered surfaces that causes the play, with no way to reduce it.

I cannot find any new replacement parts, and second hand ones may have as much wear. 

[AndyGSi]

30 minutes ago, mikepilk said:

I cannot find any new replacement parts, and second hand ones may have as much wear. 

What part no are looking for as there are numerous ones that will work.

https://www.spareparts-watches.com/product/9834333/509-184-oscillating-weight-with-ball-bearing-substitute-509-004-509-080-509-074-509-069-for-seiko-7005-seiko-7006-seiko-7009-seiko-7019-seiko-7s26-seiko-7s36

https://www.cousinsuk.com/product/seiko-part-number-from-500?code=SEI509184

Edited August 3 by AndyGSi

[nevenbekriev]

It is easy to reduce the free play of the bearing, even easier now that You have disassembled it. You need to bring the cones that form the internal part closer to each other. Of course, to do that You need to grind the downside part like I have shown in this thread.  Look at my message from January 24. Then nobody toke me serious I think.

 

Edited August 3 by nevenbekriev

[rjenkinsgb]

How about using fractionally larger bearing balls?

There is also likely to be some wear in those anyway, so even replacing them with nominally identical ones may help as bit.

Going up in size, if possible, would allow it to be re-adjusted or shimmed for minimal play. Swapping imperial<>metric for alternate sizes, even?

 

[mikepilk]

42 minutes ago, nevenbekriev said:

It is easy to reduce the free play of the bearing, even easier now that You have disassembled it. You need to bring the cones that form the internal part closer to each other. Of course, to do that You need to grind the downside part like I have shown in this thread.  Look at my message from january 24. Then nobody toke me serious I think.

As long as it doesn't take a lathe !

[nevenbekriev]

Sorry I have forgotten to add the link to the thread. Now it is there. No lathe needed, just fine diamond disk or file.

Edited August 3 by nevenbekriev

[HectorLooi]

1 hour ago, nevenbekriev said:

Look at my message from January 24. Then nobody toke me serious I think.

Sorry Neven. It's not that nobody took you seriously, it's just that we don't read Russian. 

I didn't know that the bearing was constructed this way. I always thought it was a standard deep groove bearing.

Are all rotor bearings constructed this way?

[mikepilk]

1 hour ago, nevenbekriev said:

It is easy to reduce the free play of the bearing, even easier now that You have disassembled it. You need to bring the cones that form the internal part closer to each other. Of course, to do that You need to grind the downside part like I have shown in this thread.  Look at my message from January 24. Then nobody toke me serious I think.

Great, thanks. So basically you remove some material where I've highlighted in yellow?

BTW I put it back together, just to prove that I could. It's not difficult to take apart and reassemble.

[nevenbekriev]

Yes, exactly. You can take off material from there but in the end the separator must still rotate free. Be careful - not to grind to much. 3-4 movements on the file and try the end shake, and if still big - again.

Assembling is easy, but use some grease to 'glue' the balls. When assembled, wash the bearing from the grease in petrol.

[Nucejoe]

The free play is not neccessarily due to wear, but  often due to the plate/ washer pushed outwards by weight of the rotor having overcomed the friction that holds it where put,  as Seiko just friction fitted it. 

You should first check all parts under good magnification.

In case the bearing or balls are  anything less than perfect, just replace the whole thing  with new.

Cut four small nick around the washer for tighter fit, since the washer might be pushed back again if just  refitted as it came out. 

 

[rjenkinsgb]

6 hours ago, Nucejoe said:

The free play is not neccessarily due to wear, but  often due to the plate/ washer pushed outwards by weight of the rotor having overcomed the friction that holds it where put,  as Seiko just friction fitted it. 

By "washer", do you mean the notched disc as the lower left of the photos? (That's the only item shown that seems to fit?)

That is the part that functions as the bearing cage, it must rotate completely freely, separately from the inner race parts. 

Apologies if you meant something different.

[Nucejoe]

47 minutes ago, rjenkinsgb said:

By "washer", do you mean the notched disc as the lower left of the photos? 

 Oops, washer would be the one on upper right, the looks of it is what I call it by.  

Can't just call it a bad design , rather one that sells, possibly with every seven years service.

Thanks for bringing this up, gave me a chance to explain to be clear to understand.

Since the rotor is not balanced , there is always a force exerted on the heavy side which tends to tilt the rotor and create the free play in the long run.

Rgds 

Edited August 4 by Nucejoe

[mikepilk]

On 8/3/2024 at 7:44 PM, nevenbekriev said:

Yes, exactly. You can take off material from there but in the end the separator must still rotate free. Be careful - not to grind to much. 3-4 movements on the file and try the end shake, and if still big - again.

Assembling is easy, but use some grease to 'glue' the balls. When assembled, wash the bearing from the grease in petrol.

It worked perfectly !

I have a 1000 grit diamond sharpening stone which was ideal. Sliding the washer about 100mm 4 times took off about 0.01mm. I ended up taking 0.025mm off in total, which left it spinning perfectly with very little play.

Good tip about using grease to hold those little balls in place.

[RichardHarris123]

On 8/3/2024 at 6:52 PM, HectorLooi said:

Sorry Neven. It's not that nobody took you seriously, it's just that we don't read Russian. 

Totally agree.  We definitely do take you seriously, you have proved yourself. 

[mikepilk]

34 minutes ago, RichardHarris123 said:

Totally agree.  We definitely do take you seriously, you have proved yourself. 

 @HectorLooi  The post was in Bulgarian and not Russian. Which my browser did an excellent job of translating.

I'm not sure of @nevenbekriev's nationality - his profile says Bulgaria, a country with a long and proud history and member of NATO. I'm not sure what Neven thinks about Russia, but we're not allowed to discuss that here 

[nevenbekriev]

I am Bulgarian and I live in Bulgaria. What I think of Russia... It is a long story, but we are frightened to be the next after Ukraina, together with the all Eastern Europe... I have many Russian friends and participate in the Russian watchmaker's forum, but this is different thing

3 hours ago, mikepilk said:

It worked perfectly !

I have a 1000 grit diamond sharpening stone which was ideal. Sliding the washer about 100mm 4 times took off about 0.01mm. I ended up taking 0.025mm off in total, which left it spinning perfectly with very little play.

Good tip about using grease to hold those little balls in place.

Glad to hear it worked well for You.

When I was student (back in 1992) I was on student's brigade in UK (Wrockham, Norwich) picking strawberries. There, from a carboot sale, I bought my first Seiko 5  7009 (I think it was 3.5 pounds). It was my first not-russian watch. Of course, the bearing was badly worn. When I came home, I figured this decision how to repair the bearing. I wore the watch about 10 years after that with no problems, then replaced it with quartz.

[VWatchie]

On 8/4/2024 at 1:52 AM, HectorLooi said:

Sorry Neven. It's not that nobody took you seriously, it's just that we don't read Russian.

In this day and age, you don't have to! Just right-click the page and select "Translate to 'whatever language you prefer'". It only takes a second or two. Not all languages using Cyrillic letters are Russian. The page @nevenbekriev linked to was in Bulgarian.