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center seconds movement Bulova 11BLC

dwhite

By dwhite
in Watch Repairs Help & Advice

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dwhite WRT Addict

dwhite

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This is probably a premature question but I'm about to attempt a cleaning of a Bulova 11BLC movement.  I noticed an extra gear on top of the plate so I guessed it was to run a seconds hand.  The best I could find on the internet was an arrangement called an indirect center seconds movement.  The watch does have a spring above the center wheel like the movements I saw online however it has no seconds hand at all.  I'm guessing they didn't use this arrangement to employ a seconds hand on this watch but all the stuff is still there.  Any pitfalls to working on this type of movement?  I read that this extra gear is attached to the third wheel.  Thanks!  Dan.

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wls1971 Distinguished Member

wls1971

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The spring would have held the centre seconds hand pinion in place, it is doubtful that they would have used this movement on a watch that had no seconds hand and left the pinion and drive wheel on the third wheel pinion, are you sure that the centre seconds hand is not missing ? pictures would help if you can supply them.

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wls1971 Distinguished Member

wls1971

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You should be able to find a seconds hand via Ebay or a parts suppliers, the only other thing to say when servicing these watches is that the drive wheel for the seconds hand sit on a extra long pinion on the third wheel it must be removed with care and needs to be pulled straight upwards a presto hand removal tool can be used for this I always replace them using a staking set other than that it should be straight forward to service this movement.

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dwhite WRT Addict

dwhite

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Here is the picture, sorry it took so long.  I checked and it does have a pinion for a second hand!  When you say get one from ebay or a supplier, what specs do I use?  I tried measuring the pinion with a Seitz jewel gauge but that didn't work.  I can try a micrometer but there is very little sticking up.

When you say remove the top wheel from the third wheel with a presto hand remover do I assume you do this before you take the plate off?  And when you say to use a staking set to put it back on do you mean to put the entire watch on the anvil and press on the wheel?  Again, I want to make sure we are talking about the large wheel above the third wheel.

I did see the post you mentioned but couldn't make heads or tails out of it.  Perhaps it will become clear when I take the watch apart.  Anyhow, many thanks, I have learned a lot!

 

bull-11blc.JPG

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wls1971 Distinguished Member

wls1971

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2 hours ago, dwhite said:

Here is the picture, sorry it took so long.  I checked and it does have a pinion for a second hand!  When you say get one from ebay or a supplier, what specs do I use?  I tried measuring the pinion with a Seitz jewel gauge but that didn't work.  I can try a micrometer but there is very little sticking up

You can check the watch hand sizes by using a sight called Ranfft :

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&&2uswk&Bulova_11BLC

In your case the pinion is 0.18mm for the seconds hand.

2 hours ago, dwhite said:

When you say remove the top wheel from the third wheel with a presto hand remover do I assume you do this before you take the plate off?

Yes

2 hours ago, dwhite said:

And when you say to use a staking set to put it back on do you mean to put the entire watch on the anvil and press on the wheel?

yes with movement held in movement holder there is enough clearance on my staking set

2 hours ago, dwhite said:

Again, I want to make sure we are talking about the large wheel above the third wheel.

Yes

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dwhite WRT Addict

dwhite

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23 minutes ago, Nucejoe said:

Glad center second hand pinion is found undamaged.

My question is:

Do we oil the hand and keeper joint?

What is a keeper joint?  Also, would you put a bit of grease on the little gear at the base of the seconds pinion?

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wls1971 Distinguished Member

wls1971

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25 minutes ago, Nucejoe said:

Do we oil the hand and keeper joint?

by keeper joint I assume you mean the friction spring and end of centre seconds pinion ? if so a tiny drop of 9010 can be used the springs job is to provide just enough friction on the pinion to stop the second hand moving in a jittery fashion when the watch is running.

11 minutes ago, dwhite said:

Also, would you put a bit of grease on the little gear at the base of the seconds pinion?

No not needed

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  • 3 weeks later...
dwhite WRT Addict

dwhite

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Thanks everyone for all the help.  I got the movement back together today and it runs great.  I re plated the case and polished the scratches out of the crystal so it should look good.  I will have to wait to case it because I just ordered a seconds hand from Ofrei and that will take a few days to get here.  I might have to ask for advise on inserting the stem but I'll play around with it first before I install the dial to see if I can get it to work.  Learned a lot on this one.

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