Removing a broken stem from a Speedmaster Crown

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Why didn’t my watch repair gentleman know this or do this to a rado crown I had to replace. Seems like it should be common knowledge to someone who has worked with watches for years. I’d like to ask a stupid question, are crowns threaded?
 
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Why didn’t my watch repair gentleman know this or do this to a rado crown I had to replace. Seems like it should be common knowledge to someone who has worked with watches for years. I’d like to ask a stupid question, are crowns threaded?

Yes, most crowns have an internal thread that the stem screws into.
 
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Yes, most crowns have an internal thread that the stem screws into.
Ok thanks. So I would think the stem and the tube are not specific to a watch. I don’t need to get a omega stem and tube when replacing a crown. I’m just screwing around with some old watches. I’ve changed motors, bearings etc some very small set screws I doubt this will translate to any watch skills but I’m not going to screw up old broken watches anyway. Ok that’s the last of these type of questions i realize I realize this isn’t what this thread is about.
 
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....... the stem and the tube are not specific to a watch. ..................

Quite the opposite, the tube in the case, the stem and the crown are normally specific to each model of watch. There are common sizes shared by many brands/models, but if you are replacing a stem or crown, you need to know the exact replacement combination for that watch.

And then the sizing of the stem starts. That's the fun part.
 
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Quite the opposite, the tube in the case, the stem and the crown are normally specific to each model of watch. There are common sizes shared by many brands/models, but if you are replacing a stem or crown, you need to know the exact replacement combination for that watch.

And then the sizing of the stem starts. That's the fun part.
Micronometer?
Edited:
 
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You Should find out exactly the metals involved. Following first application of alum,
you can check the piece for alum damage to metals under high magnification, before you go on to second step.
There are also many tools specially made for physical approach.
 
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You Should find out exactly the metals involved. Following first application of alum,
you can check the piece for alum damage to metals under high magnification, before you go on to second step.
There are also many tools specially made for physical approach.

Alum presents very little risk to the crowns. I've done this on crowns of various materials (stainless steel, gold, plated brass, etc.) and never had damage to the crown.
 
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Is the stem made of SS or what?

Carbon steel.
 
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Quite the opposite, the tube in the case, the stem and the crown are normally specific to each model of watch. There are common sizes shared by many brands/models, but if you are replacing a stem or crown, you need to know the exact replacement combination for that watch.

And then the sizing of the stem starts. That's the fun part.
Stems are identified by the movements caliber. You can use a stem extender, it screws onto the stem.
 
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Carbon steel.
Stems are specific to the movements by caliber, stem extenders mount on old stem, not specific and cheap.
 
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Stems are specific to the movements by caliber, stem extenders mount on old stem, not specific and cheap.

And your point is?
 
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Broke my first stem today. What a PITA.

Is this the right stuff?
Mental note - don’t get this from Amazon
 
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Pusher screws are usually stainless, so alum is unlikely to work.