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Posted

Hi guys! Does anyone know how to remove a broke stem from a watch crown! The stem piece is level with the back of the crown, so there’s nothing to grab hold of, cheers! 

Posted

I had one success (and one failure) dissolving a broken stem out of a crown with Alum.

The successes was a stainless steel crown and a milder steel stem. A Tag Heuer 2000 Automatic - here with the solution at around 60ºC I could see small bubbles coming up from the stump of the stem and it took maybe 6 hours to disolve

I tried to repeat this with another watch and it did nothing.....  This was A Bulova Ambassador with what again looked like a stainless steel crown.
 

Posted (edited)

If you see at least one thread protruding, or even a half, then you may have a chance using this "tool", but don't squeeze hard.

Lot's of patience, and if you notice any signs of loctite or other adhesives, then apply several drops of acetone on top of broken stem. Use heat (hair dryer) also. You should be able gradually turn it counterclockwise, just like i did on this broken Timex stem, which was glued with something like nail hardener. Then you can use an extender to save your broken stem.

https://m.media-amazon.com/images/I/513DVvkfW5L.__AC_SX300_SY300_QL70_ML2_.jpg

 

You can also try cutting a small grove / slot on top of the broken stem to use 0.7mm flat screwdriver.

 

Depending on the Crown material and Stem material, you can try dissolving the stem. 

IMG_4030.JPG

Edited by Poljot
Posted
16 hours ago, RichardHarris123 said:

What's the crown made off?

I’m not to sure mate! I’ve sent a picture! The crown is off a Tissot 1853 automatic limited edition T115427 A GP19 moto go watch! 

 

IMG_2371.jpeg

Posted

A few things you should find out before you can mske a decision of what to do. As Richard said, what is the crown and all of the crown components made of . Then also the stem .  The crown looks to have a steel washer that retains a gasket. So be careful with what chemicals you use to dissolve any stem adhesives or the use of heat. You might swell or melt the gasket unless you are prepared to change that also . The steel washer maybe reactive to alum. Something I've just used to dissolve a broken screw from a plate. First drilled out the centre of the screw with a 0.5mm carbide . Dipped only the section that held the broken screw in Rustins rust remover. This is 40 % phosphoric acid. 3 days and the screw remains were completely dissolved, no trace of steel in the brass threads. A black puddle left in the solution.

  • Like 2
Posted
On 4/28/2025 at 3:41 PM, ColinC said:

I had one success (and one failure) dissolving a broken stem out of a crown with Alum.

The successes was a stainless steel crown and a milder steel stem. A Tag Heuer 2000 Automatic - here with the solution at around 60ºC I could see small bubbles coming up from the stump of the stem and it took maybe 6 hours to disolve

I tried to repeat this with another watch and it did nothing.....  This was A Bulova Ambassador with what again looked like a stainless steel crown.
 

I'm surprised it only took 6 hours. What strength was the alum solution?

Posted (edited)
On 5/1/2025 at 12:55 AM, AndyGSi said:

I'm surprised it only took 6 hours. What strength was the alum solution?

I had it in a little jar in a double bath at 60ºC in a more or less super saturated solution - some crystals came back out of solution as it cooled.

Heat was really the trick - When I started at room temperature I could see a bubble form on top of the old stem and just sit there but when heated there was a constant stream of bubbles

 

Edited by ColinC
Posted
3 hours ago, ColinC said:

I had it in a little jar in a double bath at 60ºC in a more or less super saturated solution - some crystals came back out of solution as it cooled.

Heat was really the trick - When I started at room temperature I could see a bubble form on top of the old stem and just sit there but when heated there was a constant stream of bubbles

 

OK, so you don't know how much of the alum you put in how much water then?

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