Vintage AS Movement - only marking is 21

[RichardF]

I don't suppose anyone can help me identify this old movement. I'm told it dates from the 1920s. The only marking on it is AS on one side of the plate, and 21 on the other. I can't find an AS 21 movement.

The pictures are of the bare plate and also one from earlier in the dismantling process.

Also, a cheeky second question. What would the plain metal ring do (at the side of the plate in the first photo). It came off the plate I think but I don't know where.

Thanks so much for your help.

[RichardHarris123]

Albert Schild but which caliber?  We need the diameter and photos of the keyless works. 

[AndyGSi]

It's one of these AS 415 family.

https://watch-movements-archive.com/watch-movement/as-529/

[nevenbekriev]

The small ring is the crown wheel bearing.

[RichardF]

Thank you all so much for your extremely helpful replies. Exactly what this Forum is so good at.

nevenbekriev: Of course it is the crown wheel bearing! How stupid of me. Would have been stuck to the plate with old oil when I removed the crown wheel which is why I didn't notice it. Thank you.

Richard/Andy: You're right, it's definitely one of that AS 415 family. From the pictures I guess the 521, and also the 21 mark on the plate. The reason for my question is that the screw has sheared off inside the mainspring arbor so I'm looking to find a replacement. Don't want to have to try drilling it out. Would you know if this whole family have the same mainspring, and hence same arbor? You say the diameter of the keyless works would help. Which piece? All those bits are in the photo below.

Thank you all again.

 

[AndyGSi]

9 minutes ago, RichardF said:

You say the diameter of the keyless works would help.

The diameter of the complete movement and photos of the keyless works are 2 separate items.

This is what's called the keyless works part of the movement and part of yours is broken.

[nevenbekriev]

Have in mind that the thread in the barrel arbor is most probably left-hand thread. And, now that the head of the screw is sheared, the screw is no tightened any more and thus easy to unscrew. If still using sharp pointed tool doesn't help, then the easiest solution is to cut a slot in the remain of the screw. You can safely cut it through the square part of the arbor until reach the bearing pivot. I mean cutting with dremel-like tool with dental separator disk 0.2mm wide.

Edited March 31 by nevenbekriev

[RichardF]

Andy, sorry, understand your question now! Diameter is 23.2mm. And you're right, that is broken. Arm wasn't in the watch so must have happened some time in the past. Thought the crown pulled out rather too easily! So, another part to source.

Neven, thank you. I'll give that a try. So left-hand thread in barrel arbor. Is this common? Thought that was just the crown wheel.

Thank you.

[nevenbekriev]

4 minutes ago, RichardF said:

 So left-hand thread in barrel arbor. Is this common? Thought that was just the crown wheel.

It is often seen in old AS movements, and has been discussed here several times as I remember.

[RichardF]

For completeness, this build had a happy ending.

As nevenbekriev said, once the pressure was off and I finally gleaned that it was a left-hand thread I was able to remove the sheared-off bit of screw in the barrel arbor. Found another left-hand screw in one of my old movements, and hey-presto, the mainspring was all back together.

As for the broken setting lever spring, I couldn't find any movement parts for the AS 415 family, or the AS 521 specifically as this appears to be. However it turns out that this is the same setting lever spring used in the AS 340 (I was also doing up one of these at the same time so it was a completely lucky coincidence). I was able to source another battered old AS 340, got the setting lever spring out of it, fitted it to my AS 521, and happy days. Pictures show it in place. A little tarnished but working fine.

Movement is now all back together and running very sweetly.

Thank you all for your help. Appreciated.