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I have an old Waltham pocket watch movement which is missing the impulse pin (roller jewel).  I have a limited number of actual jewels and since this is just a practice movement I thought I'd try to make one out of brass.  I've seen this several times in old pieces--usually a very sloppy job.  So I got some brass stock of the same diameter as the "D" in the roller table, filed it and burnished it to a high gloss.  Then I took a small, very fine diamond file and filed it half flat to form the "D"  I then polished the face using progressively finer sandpaper on a steel block.  This works fine--so far!  Problem is separation of the piece from the stock.  Again I used a small cutting file to do this but it doesn't leave the end very pretty.  So what I've done so far is to fit the good end into the roller table.  I then plan to shellac it in place and see if I can very carefully adjust the length and clean up the end.  Has anyone done this before?  Any suggestions as to how best to do it?  

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37 minutes ago, watchweasol said:

Hi    One suggestion is to fit the brass pin in a pin vise and polish the rough end in the same manner as you have used already, assuming that the new pin is over size and can be polished back

One problem I've had with that is that after I file it to a "D" it's difficult to hold in a pin vise.  

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When working with small metal parts, (not necessarily watch parts, but this applies with those too), I will superglue the part to something I can easily hold, for example plastic card stock, or some other metal, then file away, drill, etc.  then dissolve the superglue in acetone to remove the part.

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1 hour ago, AndyHull said:

When working with small metal parts, (not necessarily watch parts, but this applies with those too), I will superglue the part to something I can easily hold, for example plastic card stock, or some other metal, then file away, drill, etc.  then dissolve the superglue in acetone to remove the part.

Yes, I think I'm gonna do that.  Thanks!

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On ‎6‎/‎15‎/‎2019 at 3:34 PM, AndyHull said:

When working with small metal parts, (not necessarily watch parts, but this applies with those too), I will superglue the part to something I can easily hold, for example plastic card stock, or some other metal, then file away, drill, etc.  then dissolve the superglue in acetone to remove the part.

I second this approach.  I'll just add heat can also be used to break down the superglue.

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