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Trying to correcly identify a wheel name for an "Ebauches Bettlach EB 1504" movement.

Vacheron7

By Vacheron7
in Watch Repairs Help & Advice

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Vacheron7 Member

Vacheron7

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Hi All.

As we are on lockdown my mum has been tidying up and she asked me if I could do anything with a locket watch which she has since she was about 20 (she is in her 70's now).

After taking a look, the watch contains an Ebauches Bettlach (EB) 1504 movement which is a Swiss, 17 Jewel, Pin Lever mechanism using a "Roskopf" construction with only three gears.

I immediately noticed the tell-tale wobble of a broken balance staff, which was indeed the case, however after ordering and re-fitting a new balance I noticed during re-assembly that there was a further broken staff on the wheel highlighted in my attached photo.

The wheel train goes

  • Barrel
  • Wheel A (damaged)
  • Wheel B
  • Escape Wheel

Cousins do stock parts for this movement, but what I can't determine is what this  "Wheel 1" would be referred to?

Standard thinking determines that this would be the "centre wheel", but as this is not centred, it should be the "second wheel"?

However, to confuse matters further, information I have found online states that the centre seconds hand is driven from an intermediate wheel "driven from the outer teeth of the second wheel" but this intermediate wheel is actually driven from "Wheel B" which I would have considered to have been called the third wheel?

If anyone can help me shed some light on this I would be extremely grateful! :-)

Cheers:
Paul. 

 

2020-04-12 21.59.00-1 - Copy.jpg

Vacheron7 Member

Vacheron7

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Hi watchweasol. 

what I find confusing is the wheel that is broken is driven by the barrel. Wouldn’t the 4th wheel be  normally next to the escape wheel, but as this only has 3 gears would the escape wheel be driving the third wheel? 

Hopefully this explains my confusion! :)

watchweasol Distinguished Member

watchweasol

Posted
Posted

Hi   As it happens I repaired a Durowe 320  which is the same construction as yours. The barrel carries the min wheel attached, the canon pinion stands on a post with the hour wheel and the rest of the layout is the same.  I believe the construction is Rospkof and the wheel designated by your drawing and that in the attached book is the third wheel.  Take a while and look at the attached book on Rospkof.  hope it helps you      cheers

TheRoskopfWatch.pdf

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Vacheron7 Member

Vacheron7

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Hi watcheweasol.

That's a fantastic resource and extremely helpful. Thank you so much. 

It is certainly referred to as the third wheel and Cousins do list a third wheel on their site so I will buy one and hope for the best!

I will read up on this style of movement from the information you have kindly provided. Because if this is successful I will need to consider what (if any) lubrication I would need to consider for the friction plate which holds the minute wheel to the barrel (as this has now been ultrasonically cleaned).

This may be covered by the information you have provided when I have had a chance to have a detailed look at it!

(I have attached a photo of the interesting barrel arrangement from my mums watch FYI).

Thanks again. 
Paul. 

2020-04-12 22.28.38-1 - Copy.jpg

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