A. Lange & Söhne

Hi all Just bought a Grand Langematik (ref 309.031) on an auction (well respected house, combined online/hammer auction). The price was....well higher than my pre set limit but you know all about the heat of the moment etc 😉 When I got home I more or less... 

Screws are part of the structural integrity of the watch. If they are loose my guess would be an impact of some type. Send it in for service. Hopefully. no big deal and an easy cheap fix.

Regarding the missing screws and due to the fact that you have no service history about this timepiece, I will send it to Lange for a full service right now. Best wishes Alkiro

It's very hard to fake a Lange, I doubt that would get past a credible auction house even without papers, so rest assured I don't think that is your problem. Loose screws are a sign the thread is worn. I have attended workshops and tried it in person, the... 

There is usually a pattern established to tighten screws in sequence. But when assembling a movement especially with blued screws I think it more likely the watchmaker undertightened them (to avoid marking the screw slot) rather than overtightening them t... 

Also, there was at least one Lange movement (can't recall which one) in which Lange customarily replaces one screw type with another screw type because the older type would loosen to easily. I recall that from years ago.

As others have said, providing a picture and indicating the position of the loose screws would be helpful. Loose screws don't necessarily indicate the watch is fake, so I wouldn't worry about that. The main concern with loose screws is that they can move ... 

The auction house will pay for a full service and all potential repairs related to the loose screws. Also sent pictures to ALS and they said that most likely the screws that were loose should not have damaged other parts of the movement. Now we just must ...