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Removing dial from a Chromachron ISA268 movement

potatan

By potatan
in Watch Repairs Help & Advice

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potatan New Member

potatan

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Hi,

I'm replacing an ISA268 movement on a Tian Harlan Chromachron Watch.  The movement was corroded by the battery.  Interesting as it has no "hands" as such, just a rotating disk that exposes a different colour of the face for each hour.

But I can't get the movement detached from the dial.  I think I have found the two dial feet, but I am confused by two screws next to the feet that appear to do nothing other than turn in their housings. I thought perhaps these would be something to do with how the dial is attached but I can't figure it out.  

I've added some pictures showing what I believe are the feet with the screws next to them - and a picture of the dial and "hand"

Any ideas?  Thanks in advance

face_hand.jpg

feet screws.jpg

foot.jpg

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Geo Distinguished Member

Geo

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If you look closely I think you will find these screw heads are eccentric and will turn away from the pins.  If they have been turned all the way around, they have probably cut a groove in the copper pin.  Look very carefully using a loupe to ascertain when the screw heads are turned as far as possible from the pins.  This is the point at which you should be able to prise off the dial.

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potatan New Member

potatan

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1 hour ago, Geo said:

 Look very carefully using a loupe to ascertain when the screw heads are turned as far as possible from the pins. 

Thanks, I'll take a look tomorrow but it's difficult to tell what is going on under the screw head even with a loop.  Plus both screws spin freely, i.e. they don't just move half a turn or something like that.

 

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  • 3 years later...
Petrus New Member

Petrus

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Hi Potaton its been 4 years since your post.

I have a question about it. Is it possible to buy a any (new) ISA268 mechanism and will this work with this watch which has no hands?

And are there any tweaks needed?

My Chromachron works but is not working as it should with a tick every hour.

 

Hope you will read this and it won't be an immense problem if you wouldn't read it.

Yours Faithfully

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