Automatic Movement Rotor Repair Fell Off!

[StuartBaker104]

I would be inclined to try the loctite route once you have confirmed the fit is reasonable. This way you get to keep the correct matching part. Buying used parts or generic parts can be a bit of a gamble.

However, loctite 222 is a thread locker designed for applications where there is a relatively large gap to fill. This application really requires a “retainer” as you should have a very limited gap e.g. loctite 620.

 

[radbrad777]

That makes sense, so how would you best apply the locite 222?  Toothpick route in the interior of the rotor - set the bearing inside and let dry for a day?

[jdm]

1 hour ago, Maxi said:

You could also try to make the hole of the rotor more little by hitting it with something which is bigger than the hole and a hammer. The hole will get little and the rotor will get in and stay there.

That has been suggested above already:

Quote

a staking set properly used could tighten the hole enough for a good fit. 

The things is, I'm not convinced that it's likely for as watch owner to posses the needed tools and dexterity.

[StuartBaker104]

The datasheet is here

http://tds.henkel.com/tds5/Studio/ShowPDF/620-EN?pid=620&format=MTR&subformat=REAC&language=EN&plant=WERCS

You need to clean the 2 surfaces with something like isopropyl alcohol on a cotton bud, then apply to both parts - a toothpick is fine.  The bearing may well be lubricated so I wouldn’t dip it in any cleaning solution, and if you get glue on the moving parts it will be toast, so take care, and use a magnifying glass so you can see what you’ve applied. You will need very little and don’t want to have to clean off too much excess when you’re done.

It’s really important that you remove the bearing from the watch to reassemble the parts, then refit when cured. Don’t try and fit it in situ.

[jdm]

1 hour ago, StuartBaker104 said:

However, loctite 222 is a thread locker designed for applications where there is a relatively large gap to fill. This application really requires a “retainer” as you should have a very limited gap e.g. loctite 620.

Correct. Just looking at how foamish 222 looks like makes you think that it is far from a common definition of "adhesive".
However, I'm also against using glue as much of possible. A philosophy point maybe, but we don't wear mechanical watches just for necessity.

[clockboy]

2 hours ago, Maxi said:

You could also try to make the hole of the rotor more little by hitting it with something which is bigger than the hole and a hammer. The hole will get little and the rotor will get in and stay there.

Personally I think this is a bad idea. As I explained in a previous post the rota has to be balanced and once you start distorting the centre you are in great danger of the rota going out of balance. 

[jdm]

46 minutes ago, clockboy said:

As I explained in a previous post the rota has to be balanced and once you start distorting the centre you are in great danger of the rota going out of balance. 

Why? If you think about it, on a rotor  all the weight has to be one side, totally unbalanced to make it work. That makes so that any infinitesimal unbalance (it's even smaller being so close to the axis) introduce by deforming or gluing is irrelevant.

[radbrad777]

I have gotten the loctite 620 and plan to remove the rotor today.  Will update soon.  For tonight, I suppose I will use the watch as a winding one.

[radbrad777]

OK so I heeded the warning and did not immediately start with loctite.  Rather, I used the little hammer found in most watch kits to gently hammer the rotor in to the weight (after unscrewing it obviously and away from the watch).  Then I re-screwed it back into the movement.  I noticed if I screwed too far, the weight scraped against the movement.  Therefore, I lessened the screw tightness and now the weight sounds much more fluid with no interaction with the movement.  That said, it looks a little wobbleish but seems to be working. Is it normal for the screw to not have to be screwed tightly? I have put the case back on and will see how it goes.

[jdm]

2 minutes ago, radbrad777 said:

 Is it normal for the screw to not have to be screwed tightly?

No, you need the screws to be tight. Try driving the rotor up a bit, again with gentle tapping on the bearing.outer race. 

[radbrad777]

ok thanks - this is the hammer and weight + rotor.  I will remove it and tap the rotor less deep into the weight?  So I will take it out and tap it a couple times in this orientation, correct?

Edited January 26, 2018 by radbrad777

[jdm]

I realized only now this is simply about an impact that made the rotor fall off... nothing is defective.

2 pages of useless speculations.. including mine's  Oh well. 

[radbrad777]

I mentioned this occurred after dropping in the first post.  That said, I was surprised a drop would cause this. The un-tightened screw did in fact fall out, so I am adjusting the rotor now. 

Edited January 27, 2018 by radbrad777

[radbrad777]

Rotor adjusted, screw tightly in now.  Lets see how long this lasts, but sounds smooth at the moment!  One other question, I have some surface scratches on the case, especially on the case back.  I have some varying grit sandpaper.  Any recommendations for the best way to take out the scratches and polish?  It is a mirrored back with a brushed finish in the middle.  Thanks

[jdm]

29 minutes ago, radbrad777 said:

One other question, I have some surface scratches on the case, especially on the case back.  I have some varying grit sandpaper.  Any recommendations for the best way to take out the scratches and polish?  It is a mirrored back with a brushed finish in the middle.  Thanks

Do not use any sandpaper. The technique is called "buffing", check: