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Any special information on 7.75x 11L Wittnauer 7TN?


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Greetings. I just bought a nice rectangular, slightly curved case, Wittnauer with a 7TN movement in it. I'm very impressed with the finish on the movement, with its mirror-polished winding wheels, highly polished pallet-fork, gold center and third wheels, and jewel settings. I'm just tearing it down for a clean and oil, and was wondering if there is anything I should watch for with this movement? The balance was a bit tricky to maneuver out. That got me thinking that there may be some hazards that someone may help me avoid with this movement. It's a rectangular movement that is 7 3/4 x 11 lignes. If there's something I should know, please share your knowledge so I don't learn the hard way. Thanks.

 

 

Edited by MrRoundel
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9 minutes ago, MrRoundel said:

Greetings. I just bought a nice rectangular, slightly curved case, Wittnauer with a 7TN movement in it. I'm very impressed with the finish on the movement, with its mirror-polished winding wheels, highly polished pallet-fork, gold center and third wheels, and jewel settings.

Sounds nice, any pic for others to appreciate?

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Sorry, that was silly of me not to post some images as I beamed about the watch. I'll attach the auction I won it in, as well as some pic's I took as I dismantled it. Needless to say, the watch was undervalued or missed by the market. Seriously, this is a very well finished grade, and the case is quite presentable.

Sorry about the image quality. I just took them for reference. It's all about the polished steel parts. Cheers.

https://www.ebay.com/itm/VTG-Art-Deco-1930-039-s-Brown-Face-Stepped-Case-Wittnauer-Parts-Repair-/232633951949?_trksid=p2047675.l2557&ssPageName=STRK%3AMEBIDX%3AIT&nma=true&si=6LKeT04jGXX1XLHK0jGnSx9zB4M%3D&orig_cvip=true&rt=nc

DSC06044.JPG

DSC06046.JPG

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Well, she's cleaned, oiled, reassembled, and running pretty strongly. I don't have a timing machine so I have to just see how it keeps time while it's on my wrist. I had a beautiful Watchmaster G47 timing machine, but it was impossible to get the necessary paper rolls for it so I got rid of it. Someday soon I'll get one of those new electronic ones that a lot of guys are using.

Anyway, the biggest tip that I'd give on this Wittnauer 7LT is to be extra careful when replacing the balance in the watch. It comes in from the side and has to get under the center-wheel and the fourth-wheel. It's very easy to get the hairspring hung up on top of the center-wheel, so beware of that. Wittnauer was kind enough to provide a channel in the pillar-plate that lets the lower balance pivot, roller-table, etc., drop a bit lower to make it doable. Still, it's a bit of a challenge.

The arrow in the image points to the channel in the pillar-plate. As I said above, it's a very nicely finished movement. It does seem that all of the 7LT movements were not finished the same. The Revue model, along with others I've seen don't have the polished winding wheels. I guess that was about different years of production. Cheers.

 

7LT Runway.jpg

Edited by MrRoundel
Removed dark image. Added better image.
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Oh, and check that statement about the gold third and center-wheels. They may not be gold. They are, however, of a different composition from the fourth-wheel, which led to what may be my confusion. Still, the beautifully polished pallet-fork, winding wheels, and under-dial setting parts, impress the heck out of me. The pallet-fork reminds me of those found in early Howard pocket watches. They were beveled, polished, and counter-poised. Cheers.

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