a galled watch case?

[horologist]

I was informed by a watchmaker that on two occasions he had 2 watches that the case back had galled onto the case. He said that it is very rare but when it happens is when the tips of the case threads cold weld onto the case and in many situations the watch case had to be destroyed as it could not be opened. It is NOT cross threading. It can also happen to a new watch that has not had the threads lubricated. Has anyone ever experienced this with a watch case and if so did it happen half way when removing the case back or when putting it back on? Thanks for your replies

[highoeyazmuhudee]

something similar happened to me, i had a disassembled case that i ultrasonically cleaned, let dry and screwed the case back back on, next day it wouldnt open, nothing could get it open. i held a lighter to the case back for a while and that eventually allowed me to loosen it but the threads looked different, like pitted or gnarled. when i originally screwed it down it was smooth and there was no indication of a problem. im not sure if this is the same as what your describing or not.

[horologist]

something similar happened to me, i had a disassembled case that i ultrasonically cleaned, let dry and screwed the case back back on, next day it wouldnt open, nothing could get it open. i held a lighter to the case back for a while and that eventually allowed me to loosen it but the threads looked different, like pitted or gnarled. when i originally screwed it down it was smooth and there was no indication of a problem. im not sure if this is the same as what your describing or not.

Yes, it seems like what you have just described is also galling. You were lucky to get it open, I guess that you meant that the threads were smooth prior to closing the case back?. It is very common with stainless steel and titanium but not with gold. I have been informed that to prevent this from happening you must lubricate the threads with silicone grease or fomblin ( which is an expensive alternative). This is one of the many reasons I would never invest in a brand new genuine stainless steel Submariner/ Daytona etc. as this overlooked phenomena can also happen even to these most expensive timepieces where the greasing of threads can be easily overlooked on the production line. I have also spoken to some of the most artisan watchmakers who seem pleasantly informed and surprised when I ask about what grease they use the case threads.

[stiff muckler]

Dis isn't usually so much of da problem wid da Bergeon watch case opener. Hygene and lubrication helps. Da hand held wrench ist woefully inadequate fur da tight ones.

sm iiH!

[highoeyazmuhudee]

Dis isn't usually so much of da problem wid da Bergeon watch case opener. Hygene and lubrication helps. Da hand held wrench ist woefully inadequate fur da tight ones.

sm iiH!

its not a matter of it being tight, or having the proper tool in this situation

[stiff muckler]

Ja, stiff has heard dis before. Da bench mounted Bergeon or even da Horotec opens dem.

sm iiH!

Edited March 26, 2012 by stiff muckler

[horologist]

i held a lighter to the case back for a while and that eventually allowed me to loosen it but the threads looked different, like pitted or gnarled.

Did the case back screw back on or was it more difficult to close after this with threads that seemed pitted or gnarled?

[highoeyazmuhudee]

Did the case back screw back on or was it more difficult to close after this with threads that seemed pitted or gnarled?

screws on half way but wont go any further

if i can somehow retap these threads i could maybe use it? but i dont know the tap size and its probably over $50 with no guarantee of it working.

[wat44]

it also happens in much larger threads eg engineering applications with bolts - nothing to do with lubrication, unfortunately

people solve this by using different grades of steel - which wont help you at all in a watch case!

[Jkay]

Anti-Seize compound is make for this kind of application.

It's a copper powder suspended in gel.

[stiff muckler]

Typical of da poor materials and da worn out tooling.

Da uhrmacher would empty da case, apply da extra fine lapping compound and utilizing surfactant and water would dress da threads by repeated, progressively deeper engagement and da periodic cleaning. Da rookie vill "screw" dis up every time by going too deep and "locking" da abrasive in place. Da uhrmacher then polishes da threads to remove any traces of loose metal and cleans dis residue. Simple - if you are patient!

sm iiH!

[Logan]

Titanium is especially prone to this, just ask any cyclist whose been sucked in by titanium bolts and hasn't used anti seize.

The better ti bolts with rolled threads are a lot less susceptible t this compared to machined threads btw.

A touch of penetrating oil and the right tool usually frees things up. Somewhat ironically thread lock compound actually prevents galling too although I wouldn't use it on a case back.

[horologist]

it also happens in much larger threads eg engineering applications with bolts - nothing to do with lubrication, unfortunately

Regarding lubrication, the following article relating to galling of stainless steel strongly suggests lubrication as one of the preventative options at 2.

http://www.estainles...fstainless.html

However, for this very reason, I will not invest into a genuine stainless steel high end timepiece as it can also happen with a new one where the antiseizing lubricant could have easily been missed at the production line and then try to prove who is to blame.