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7750 Part Question


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Ive been working on 7750s for over a year now and have run across all sorts of variations etc but the lock 2 functions pn 8200 pictured below is a first. Anyone shed some light on it??acf37ae16451ef6e8cd63919cb5fd270.jpg

 

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I've never seen one like that on ETA 7750. Is it from a clone?
J
I dont know. I bought a spares and it came off it. Could very well be from a clone but the main plate is def an ETA. It seemed as though it was all original at least as far as I could tell.

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I can't tell from the pic, but is it all metal? Likely a variant as you already know....all I found was an older Horotec guide with this (33 Var), but yours doesn't have the second cutout:
1614624965_ScreenShot2019-05-29at10_07_29PM.png.e4fef21336c9bf9dd7ca969c619d7d68.png
Its like a flat peice of plastice with a wire sticking out. Appears to be teflon or some soft plastic. I have a clone on the way so well see whats inside it. Thanks for looking into it. I wonder if itll perform as the normal one. I honestly dont see the advantage from a manf standpoint making it this way. It almost would seem like itd be more costly than the stamping that the eta parts are made from so thats why im curious.

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It may be cheaper to cut out polyethylene  (cheaper than teflon) than to do stamping/grinding metal. It will be informative to see what the clone has, but I did see this on the 'bay so maybe it is ETA:

248220142_ScreenShot2019-05-29at11_54_56PM.thumb.png.a18040db575072d849f569948b0dd7dd.png

Edited by noirrac1j
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I got a 7750 which turns out to be the original made by valjoux before the company was bought by eta. Dosn,t say eta7750 rather val7750. This varient too, came with plastic lever, Dr ranfft tells about the lever in diferent variants, I think the plasic is not a sign of inferior material or clone. Chrome plating is awful and I have never seen a balance wheel move this free in any movement. 

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I got a 7750 which turns out to be the original made by valjoux before the company was bought by eta. Dosn,t say eta7750 rather val7750. This varient too, came with plastic lever, Dr ranfft tells about the lever in diferent variants, I think the plasic is not a sign of inferior material or clone. Chrome plating is awful and I have never seen a balance wheel move this free in any movement. 
Would you mind posting pics for the record????

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It may be cheaper to cut out polyethylene  (cheaper than teflon) than to do stamping/grinding metal. It will be informative to see what the clone has, but I did see this on the 'bay so maybe it is ETA:
248220142_ScreenShot2019-05-29at11_54_56PM.thumb.png.a18040db575072d849f569948b0dd7dd.png
I agree, however the secondary labor to install the wire is where the cost over run I think would occur as it would have to be done by hand. Anyhow.....it looks like the one I have is in fact an ETA part by your findings. This is good stuff for the 7750 body of knowledge. As always thanks for your input. BTW.....im ready when you are for the next iteration of 3D prints for your project. I posted my thread for the first Bronze CNC run. Im slowly getting up to speed on the CAM programming for the machine in fusion 360. If the machine will do what I think it will do we'll have metalic options at least in soft metals such as bronze.

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1 hour ago, noirrac1j said:

So many watches, I sometime slose track of what I've overhauled, but I keep good records....I HAVE worked on a Valjoux 7750 with this same plastic part. It was a Lorenz chrono:

reassemble_00001.pdf 2.54 MB · 2 downloads

reassemble_00002.pdf 3.24 MB · 0 downloads

reassemble_00003.pdf 3.75 MB · 0 downloads

so it's the same as in my movement.....

s-l1600c.jpg

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2 hours ago, bjd1020 said:

I agree, however the secondary labor to install the wire is where the cost over run I think would occur as it would have to be done by hand. Anyhow.....it looks like the one I have is in fact an ETA part by your findings. This is good stuff for the 7750 body of knowledge. As always thanks for your input. BTW.....im ready when you are for the next iteration of 3D prints for your project. I posted my thread for the first Bronze CNC run. Im slowly getting up to speed on the CAM programming for the machine in fusion 360. If the machine will do what I think it will do we'll have metalic options at least in soft metals such as bronze.

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Great information to have on the 7750. I am going to test a piece of curved plexi for the crystal and also have to try the drill holes for the stem/crown. I'll let you know when I get all that sorted out. Thanks!

J

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