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Posted

Yesterday I managed to start work on my Seiko chronograph. "Autowind" on the forum was kind enough to donate a watch that had the same type of stem and crown that I required, I really can't thank him enough for that.

I thought all I had to do was to remove the stem from one watch and fit it to the other, but unfortunately (or luckily) the stem was too long. I thought This will be an easy fix, just unscrew the crown and shorten the threads by 1mm. Well I gave it my best shot but it refused to budge, I think it had been fitted using Loctite. As this stem is rather special, it has a spring loaded gear on it to drive an internal rotating bezel, I was frightened I would break it.

After a bit of deliberation, I came up with the idea of using a soldering iron to apply intense heat to the crown. I held the stem tightly in a pin chuck and applied the soldering iron to the crown. After about thirty seconds of applying heat, I used a pair of pliers and the crown unscrewed very easily.

The only caveat, if the crown is not stainless steel or chrome plated, put some high temperature grease on the crown to prevent solder adhering to it.

post-124-0-06626700-1411485480_thumb.jpg

  • Like 1
Posted

I have had to do similar in the past - my method was to heat up a sheet of brass over a spirit lamp and then to leave the stem on the brass and that did the trick. Your method seems quicker and less complicated :)

Posted

Very nice indeed, I usually turn - carefully - first as if tightening and then the opposite direction...but then I haven't found a really stubborn stem yet! I like this idea a lot!

Posted

If proper loctite is used it will soften with heat.

Heat the stem,hold it with a pin vice and twist. It should let go

p.s: sent from my s****y phone so sorry for typing mistakes

Posted

Heat usually solves this problem, some loctite types need this to be loosened. The expansion/contraction also helps.

 

This is fine for retrieving stems but if you're trying to recover a crown then you will need to be prepared to sacrifice and dig out the remains of the old o-ring it there is one.

 

Anil

  • 2 months later...
Posted

In my engineering days when we used loctite threadlock on screws, we used to just give the screw head a sharp tap!  This 'cracked' the loctite in the threads and enabled easy removal.  Not sure if this would be easy to do with a crown/stem !!

Posted (edited)

I personally turn the crown as if to tighten and then back to loosen it. It never fails! Sometimes heat is necessary whey they have used THE OTHER locktite! (read glue instead of thread lock)

Edited by bobm12
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