Winding stem removal from crown

[m1ks]

Now, prior to about half an hour ago, the snapped stems I've encountered have either had enough protrusion or the crowns have been toast anyway.
Then some idiot, (Ahem), fumbled a movement he's readying for a strip just after refitting the stem which then encountered floor and snapped the stem flush with the crown thread, removing and replacing the stem from the movement isn't a problem but I would like to, if possible, remove the thread from the crown, (it's a panerai/parnis style wide thin button which is clamped to the case and lo and behold, they're hard to find cheaply like every other type of crown!)

So my question is, has anyone ever succesfully managed to do this and is there a way to remove it?

Thanks

[watchweasol]

Hi M1ks       If there is any protrusion and depending on how tight the stem is with a sharp tool you may be able to unscrew it and I mean maybe I have managed one or two like that. Best to try that method before resorting to the drill.  good luck

[m1ks]

2 minutes ago, watchweasol said:

If there is any protrusion and depending on how tight the stem is with a sharp tool you may be able to unscrew it

Thanks, but sadly no, It's right on the rim of the crown thread, I've tried a small screwdriver and some 'odd job' tweezers, drilling has crossed my mind but it's incredibly fine and ideally a pillar drill dremel type setup would be preferable which I don't have.
I have a vague recollection of watching a video some years ago showing a watchmaker using an acid which attacked and dissolved the hardened steel of the winding stem but not the coated winder but don't recall details or even if i'm just imagining it. 

[watchweasol]

Hi M1ks       I have heard if this method but never tried it  Acid is dangerous stuff. I will have a look round on the net if I turn up anything I will let you know.

[watchweasol]

Hi  Me again   you were right   aluminium sulphate is used, a hot solution of Alum will dissolve the steel but will not harm the brass.  Apparently it is available at the super mkt in the spice rack !!! or so the blurb tells me.  I just googled dissolving broken steel screws and there it was..  cheers 

[m1ks]

5 hours ago, watchweasol said:

Hi  Me again   you were right   aluminium sulphate is used, a hot solution of Alum will dissolve the steel but will not harm the brass.  Apparently it is available at the super mkt in the spice rack !!! or so the blurb tells me.  I just googled dissolving broken steel screws and there it was..  cheers 

Wow! At the supermarket haha.

But thank you very much for finding this, I knew I'd seen it somewhere, would love to remember where.

I'll have to look into this, has to beat trying to drill it.

[m1ks]

A bit of a look with this new info and it seems eBay or amazon are my options, all the references to alum in the supermarkets seen to be US and it's certainly nothing I've seen in a UK one but it's really available it appears online so I'll have to get some and try it.

Thanks again.

[watchweasol]

Hi    Must admit not seen any in the UK supermarkets............Your welcome

[AndyHull]

I believe Alum is also used in old fashioned razor shaving, to "tighten the skin" and also stop the bleeding from shaving nicks, so you might like to check you local supermarket for Alum shaving stick. Often Asian grocery stores have alum shaving blocks. I presume they are more popular with ex-pat Asian gentlemen of a certain age.

[philipk5]

I am in the UK and I got some from Asda (Pharmacy dept, not grocery section!) a few months ago. Took a while to explain exactly what it was, and even longer when the staff insisted on knowing what I wanted it for. Thought things would speed up when the Pharmacist was summoned but he claimed never to have heard of Alum. They referred to their suppliers catalog and a few days later it arrived. I dissolved as much as would dissolve in hot water and dropped in the crown/stem. After a week or so (prodding regularly with a pin) the crown was stem free. Not the quickest job but for me at that time it worked.  Hope this helps.

[m1ks]

8 hours ago, AndyHull said:

I believe Alum is also used in old fashioned razor shaving, to "tighten the skin" and also stop the bleeding from shaving nicks

I knew I'd heard of it, barbershops used to sell it when I was a kid.
 

 

7 hours ago, philipk5 said:

I am in the UK and I got some from Asda (Pharmacy dept, not grocery section!) a few months ago. Took a while to explain exactly what it was, and even longer when the staff insisted on knowing what I wanted it for. Thought things would speed up when the Pharmacist was summoned but he claimed never to have heard of Alum. They referred to their suppliers catalog and a few days later it arrived. I dissolved as much as would dissolve in hot water and dropped in the crown/stem. After a week or so (prodding regularly with a pin) the crown was stem free. Not the quickest job but for me at that time it worked.  Hope this helps.

Thanks PhilipK, Explaining to chemists is a nightmare at times.
Last time I tried was when I wanted a huge syringe for brake bleeding purposes, (they make great self bleeders), it was like an inquisition, I felt like saying, come on, if I intended to inject myself with anything in a syringe that size it wouldn't be a problem for long! (unless it was gamma irradiated and I became a mega hulk)
Ultimately, I picked up a great one from the local vet, they sell them in kits for bottle feeding lambs etc.
Which brings the other point, I'm in the Scottish highlands, if you search on google maps for a**e end of nowhere, you'll find it, which sadly means an 85 mile trip to the nearest town and the local pharmacy is utterly useless unless they can pluck it off a shelf with a brand name attached.
All that written however, I've ordered some from Amazon and hopefully will have it in a day or two.
Big thanks for the all the help and i'll update with progress.

[watchweasol]

Hi M1ks   Iam In the NE Scotland  Fraserburgh understand the problem  Andy has mentioned it the chemists sell a stick called Nix or Styptic pencils just solid aluninum sulfate   I EVEN HAVE ONE. not that the modern razors cut like the  7 o'clock blades of old.

[m1ks]

Ahh, cool, nice to know i'm not on my own up here, lol.
I'm next to the Isle of Skye.

Styptic pencils were the staple carded anti shaving cut thing at the barbers, used to fascinate me when I got haircuts as a kid, strange thing is, by the time I was shaving i forgot all about them and old school barbers were becoming a thing of the past.

[AndyHull]

2 hours ago, m1ks said:

...
Which brings the other point, I'm in the Scottish highlands, if you search on google maps for a**e end of nowhere, you'll find it, which sadly means an 85 mile trip to the nearest town and the local pharmacy is utterly useless unless they can pluck it off a shelf with a brand name attached.

...

I suspect I'm not that far from you in that case, I'm not actually in the middle of nowhere, but you can just about see it from here. I'm a few miles south of Perth (the original Perth, accept no substitutes), just off the A9 as you head south towards Stirling.

[m1ks]

In highland terms, we're practically neighbours,
I'm on the opposite coast and a bit higher up, about 150ish miles, near Skye, I pass near there on the way to see my son in Glasgow though.