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Bulova 6CF Movement

Folkvisor

By Folkvisor
in Watch Repairs Help & Advice

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HSL Distinguished Member

HSL

Posted
Posted

Well hard to say but if we would start some were you could start like this..
1. Release all tension from the mainspring( move the click from the teeth)

2. Take away the balance.
3. Take away the pallet fork.
4. Wind up the movement slightly (slow)

If the escapement wheel turns smoothly the fault is in the area we removed. If not we know it is either in the dive train or the motion works.

If the escapement wheel turns then start with putting back the pallet fork. Use a toothpick to manipulate the pallet fork and see if you get some action on the escapement wheel. Sometimes it has a wee bit to much oil and don't get that snappy action.

If it moves you for sure have your problem in the balance or hairspring.
 

After ticking of these boxes I'm sure we could find what is wrong with the little beauty..

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HSL Distinguished Member

HSL

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Posted

Try to clean of the pallet fork crystal and pallet cock  crystal with rodico, sounds like you got a little dirt or excess oil either there or in the balance crystals. sometimes when one cleaned the balance crystals one might have switched the upper and lower one. 
Before putting the balance in put the pallet cock in the upper position..

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yankeedog Distinguished Member

yankeedog

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Posted (edited)

Frustrating...do the gears spin when you wind it with the pallet and balance removed?.I apologize for asking if you have already answered.is the hair spring oily or sticking to itself?

Edited by yankeedog
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Folkvisor Super WRT Addict

Folkvisor

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It is working albeit slowly. I have yet to replace the end jewel in the top of the balance bridge but that shouldn't be the reason it works slowly. I'll oil it - again. But I hesitate to do that because it has already been oiled.

All the wheels have end-shake and the pallet fork moves more quickly now when I nudge it with a toothpick. The pivots on it aren't bent. No pivots look bent and all the jewels are good. I'm still not working properly.

I'm happy it is working but it can still be improved. I still need to oil the pallet stones so that may speed it up a little.

 

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nickelsilver Distinguished Member

nickelsilver

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Did you peg the jewel holes for the pallet arbor? They have to be truly spotless. It doesn't take much at all to suck all the power. With the watch unwound and balance out you should be able to tilt your movement holder and give it a little rap on the bench top one way and another and get the pallet to move around between its bankings. If it isn't absolutely totally free you'll never get any further. If you determine it's fine then you can proceed to the balance wheel (wait- stick the fork horns in clean pithwood a few times). Power down fork out, install the balance and a little twist of the movement holder should set it in motion for quite a few seconds. If not, start looking at why (hairspring distorted or rubbing, muck in the jewel holes). I've seen an almost invisible strand of dust that was clamped under an adjoining bridge that just came in contact with the balance that caused a lot of frustration.

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Folkvisor Super WRT Addict

Folkvisor

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Thank you for all your suggestions; they were extremely helpful. I especially like your suggestion re pithwood. I used it to reclean the pallet jewel ends.

I checked the pallet arbour jewel holes and I cleaned the pallet jewels; their ends were dirty. The balance spring was fine. 

I have the movement working now but I still have to put back the balance cock end jewel. 

The amplitude wasn’t good until I oiled the pallet stones. It has improved greatly.

When I get the oiled endstone back in I’ll put it on my time grapher and see what kind of reading it gives me.

These are really quite amazing little machines. You'd never expect a car to run 24/7/52 year after year!

Edited by Folkvisor
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