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Hypothetical Skeleton Movement Eta 2801-2

bobm12
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bobm12 Distinguished Member

bobm12

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So, if I wanted to case an ETA 2801-2 -- or similar -- which is a skeleton version in this particular case, and therefore has no dial to offer support to the hour wheel (and no friction face down) Does it use a special pinion wheel? What is the most popular solution? (I've seen this version around and was wondering about it)

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Geo Distinguished Member

Geo

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Hi Robert, here's my take on it.

The plate that holds the minute wheel in place would appear to be the key to this. The captive minute hand will prevent the cannon assembly falling forward, so when the hour wheel is in place and the minute hand is fitted, it will keep the whole lot together.

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anilv Distinguished Member

anilv

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Dear Bob,

 

If the watch is originally made as a skeleton (as opposed to being skeletonised by an enthusiast), then the manufacturer would have made it so that the hour wheel can't come off.

 

The hour wheel is the last wheel on and is retained by the dial/dial washer. Theoretically the minute hand will retain the hour hand/wheel from coming off but the hour wheel may skip as the hour wheel/driving wheels are quite thin.

 

I can think of 3 options...

 

1. You could fabricate a spring off one of the dial side screws..(the setting lever bridge?) to hold the hour wheel down.

 

2. Use clear plastic to make a dial, the dial (with movement ring) also serves to position the movt in the case.., correct height in the case so the crown tube aligns correctly with the stem 'hole'. A clear dial of the correct thickness would help.

 

Finally...

 

3. You could also skeletonise the original dial.. leave the dial feet in place and cut/drill out strategic areas..a bit fiddly but do-able.

 

Anil

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naugamonster New Member

naugamonster

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Hey @bobm12, I have a similar skeleton problem. I took a skeleton Asian 6497 and cased it in an Otto Frei #10 case, and have been having a hell of a time keeping the hour wheel from slipping ever since. I attempted to use a crown o-ring to keep it all tamped down, and that ended pretty badly. How did you eventually solve for this?

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bobm12 Distinguished Member

bobm12

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Wow, I hadn't seen this post in ages...Sorry Anil, I didn't see your excellent response! I appreciate it and learned some more!

naugamonster, I don't work on skeletonized movements so this was all hypothetical...from a long time ago (old thread). I'm sorry but I never did work on any...I don't usually like those movements and prefer the regular ones. I did come across some rather "skeletonized" and old/vintage Swatch ETA 2840 which use the plate that holds the minute wheel (modified for that purpose) to do the job. In my mind, if you could get your hands on one of those and the movement is of the 2801 family you may be able to use the same plate (interchangeably). For the 6497 I believe the "forum" in the TZ course has dealt with it in its own way -- found in the old posts section --...you might want to ask the instructor if you are a student.

As Anil said, they usually have their own solution when first acquired...unless someone has tinkered with the one you have previously and lost the part or something.

Do you have a picture showing the movement and trouble area? It might be helpful in case I or any other member can help.

Cheers,

Bob

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naugamonster New Member

naugamonster

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3 hours ago, szbalogh said:

Skeletonized movements have the hour wheel retaining plate/spring screwed to the baseplate. No dial needed.

Unless they are cheap Chinese 6497 clones...I bought this a while ago to disassemble/reassemble for practice, and later, tried to case as a gift. It's been a headache. The keyless works is a mess, too.

skel_6497.JPG

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szbalogh Super WRT Addict

szbalogh

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1 minute ago, naugamonster said:

I'll note that that tiny little brass washer in the photo did NOT come with my movement, and that's probably the source of my problems.

Meanwhile checked my 2650 skeleton movement, it has that hour wheel retaining plate. But the 6497 surprisingly missing it as can be seen on all pictures google pops out.

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naugamonster New Member

naugamonster

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7 minutes ago, szbalogh said:

Meanwhile checked my 2650 skeleton movement, it has that hour wheel retaining plate. But the 6497 surprisingly missing it as can be seen on all pictures google pops out.

Heh. Yeah I checked my 2650S last night and noticed the plate. The 2650 is 12L (27mm) diameter. Do you know where I can find movement casing rings (plastic or otherwise) for something like that?

IMG_20160514_095917852.jpg

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szbalogh Super WRT Addict

szbalogh

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Well, i suggest You not to go with this movement. It is a really low end basic one. I got mine for 5 USD in a complete watch in an auction. Poor guy suffered all of my learning practices and still working :)I would stick to the 6497. Dont know where to buy spacer rings. 

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bobm12 Distinguished Member

bobm12

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You can probably use some Seiko case for the 2650 as long as the stem lines up...the Seiko movement is about 12 ligne if I'm not mistaken so the well in the case should be ok...just a guess. The ring could be ordered from some suppliers like ofrei and cousinsUK by size or made with any material you can think of...one expensive solution that requires some work is using Speedi-fit...

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Alastair WRT Addict

Alastair

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On Accutrons--The Minute-Hand holds the hour-wheel in place in the spaceview models with no dial. There is no added keep-plate or other item for the hour wheel.

Is it not possible to drive the minute-hand on a little deeper to do the same here?

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