Revue/MSR T43 unusual balance cap jewels, are they correct ?

[mikepilk]

Stripping an  MSR T43 movement, I noticed too much end float in the balance, and then found these cap jewels.

I've never seen any like it. The jewel is flat, which may account for the excessive end float, the pivots appear OK.

On the Incabloc site they don't reference T43, but for T44 T46 the cap stones are 122.11 

which are the same as ETA 2824, 2892. 

Anyone seen any of these, are they correct ?

 

[rogart63]

Never seen that. If original? Why a cut out on a balance jewel? 

[mikepilk]

1 hour ago, rogart63 said:

Never seen that. If original? Why a cut out on a balance jewel? 

Strange aren't they !

Maybe so that you can oil without removing the jewel ?

[nickelsilver]

I've seen cutouts on train jewels with caps that were pressed in. To facilitate cleaning. Never on an Incabloc though. In this case I imagine it was to allow cleaning assembled, which became sort of accepted by some out of desperation in the late 70s to 80s.

[WatchMaker]

Intriguing!

This chap had the same observation... https://www.thewatchforum.co.uk/index.php?/topic/108514-incabloc-query/  ... so it seems this is a feature!

And yet if I go to a close up of another T43 movement and zoom in on the balance I can't see any reflection anomaly to indicate a cutout.

Maybe something MSR introduced in the movement's history?

[mikepilk]

I've changed them for the normal shaped ones (122.11) but still have too much end float.

Maybe  I can push the lower Incabloc in a touch.

[nickelsilver]

I've changed them for the normal shaped ones (122.11) but still have too much end float.
Maybe  I can push the lower Incabloc in a touch.

They wouldn't change the endshake. All are flat (with the exception of some that had offset concave sections, very rare).

[mikepilk]

1 hour ago, nickelsilver said:

1 hour ago, mikepilk said:

I've changed them for the normal shaped ones (122.11) but still have too much end float.
Maybe  I can push the lower Incabloc in a touch.

They wouldn't change the endshake. All are flat (with the exception of some that had offset concave sections, very rare).

The cut-out ones are flat both sides - unlike the 'usual' ones with one convex surface. 

The watch over-banked when I got it, and the guard pin has a bend in it, so someone's been playing with it. 

I need to see how the pallet fork and guard pin sit, then decide what to do. The pivots look OK, so I'm not sure where the problem is.

[clockboy]

Not all end cap jewels are domed in shape some are flat. The cut out is new for me and does not make a lot of sense. I would have thought the lubrication could creep away.

[rogart63]

Make no sense to me either. You oil the jewels when service and then it's not needed until the next service. Only russian movements need extra oil once a month. At least so it seems to be when opening then up  

[Nucejoe]

I have seen cut cabs used in other makes too. I am pretty sure on bulova 11blacd.

I too thought that is likely to give easy access for oiling. Then thought anyone who can oil pivot through this cut would do it easier with the usual method. Plus oiling the cab itself  involves more than just pouring oil on it.

We all seen cases of cabs stuck in place and sometimes are real pain to remove, the cut lets you pry the cab open/seperated  with an oiler or needle. That too can be regarded as an advantage.

[rogart63]

Wouldn't be very prone to breaking when having a cutout like that? Have an 11BLACD here that i am going to service. Would be intresting to see if it has such endcap.