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Snapped date and time stem - Rotary


AndyT

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Hi,

Thanks again and its nice to be here. 

I've managed to snap the stem on my date and time adjuster on my Rotary Chronospeed. Its not expensive, more sentimental. 

GS03351 /19 (12881)

Could anyone post a link to replacement? 

Thank you so much for any help 

20210117_122705.jpg

20210117_122638.jpg

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The case reference is not important, you need to look at the identification on the quartz module. For the best results I recommend you give it to a watch shop, it should not be an expensive repair. 

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I may need to correct myself. For an easy repair the crown stem must be of the threaded type and the repairer able to remove the stump from the crown - but I can't see enough about this in your picture. There are good techniques to do that, but if he won't  be able to, he will want to replace the crown as well, which being of the screw on type may be difficult or impossible to find  identical to the original. You might even hear about the claimed need  to replace the pendant tube as well, and be given an estimate higher than the material value of the watch. Good luck.

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Hi  For your information   the whole  Miyota OS20  movement costs £15 from Cousins, they usually come with a stem attached. All you need is to recover the crown. If the crown is brass this can be done by dissolving the broken steel stub in a solution of ALUM which will eat the steel but not the brass.

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20 minutes ago, watchweasol said:

Hi  For your information   the whole  Miyota OS20  movement costs £15 from Cousins, they usually come with a stem attached. All you need is to recover the crown. If the crown is brass this can be done by dissolving the broken steel stub in a solution of ALUM which will eat the steel but not the brass.

I have seen "alum" mentioned several times for this purpose.  My googling yields several types (potassium, ammonium). Which kind do you use?

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Thanks everyone 

 

I've managed to remove the broken stem from the crown and also released the snapped stem from the watch internal.

I've picked up a new stem for £5 and job sorted. 

 

You guys are awesome ? 

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27 minutes ago, AndyT said:

I've managed to remove the broken stem from the crown and also released the snapped stem from the watch internal.
I've picked up a new stem for £5 and job sorted. 

Very good. Because of the screw in crown measuring the stem before cutting is a bit more complicated. If you will want, ask here when you're ready and I'll tell you my method. I also recommend that you use a mild locking agent on the crown.

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44 minutes ago, AndyT said:

Oh no! I thought it was just a straight forward stem replacement.  I had no idea that it had to be cut! 
Is the crown end that needs cutting ? 

That's why I was recommending you bring the watch to a repair shop. One that is totally new to watch repair can't know how things a correct and doesn't have the correct tools.

However since no recommendation can prevent people from doing whatever they want to their property, here a relevant video by our Host Mark Lovick. Note that doesn't cover the extra measuring steps needed with a screw in crown.

 

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