Tricky screw-back case

[bjcomix]

Hi everybody. This is my first post. I recently acquired an open face side winding Waltham pocket watch. The watch has a threaded bezel and case back. Unscrewing the front bezel was easy, however the back seems almost impossible. Any suggestions for unscrewing a stubborn case back? Thanks.

[Bob Tascione]

Welcome to the forum bjcomix!
Placing a little penetrating oil along the case/case back seam and letting it sit for a day will usually do the trick. If it's still stubborn reapply the penetrating oil and tap the case back with a piece of hard wood occasionally. To give you a good slip free grip you may need to use something like a rubber dish washing glove to grab the back. I've also found at times just twisting gently rather than trying to force it will loosen it right up. I have no idea why that works but can't argue with success. Also for penetrating oil I use Automatic transmission fluid. You can also use brands like Marvel Mystery Oil, etc. I keep a plastic squeeze bottle around with ATF cut with some acetone (thins it even more) and use it often for stubborn clock and watch screws and locked up tools.
Hope this works for you bjcomix,
Good luck,
Bob

[bjcomix]

Wow. Thanks Bob. The oil trick worked like a charm. Opening the back revealed a gorgeous highly detailed 17 jewel movement with an interesting regulator shaped like a sheriff's badge.

[Bob Tascione]

You're welcome bjcomix,
Good to hear it worked for you.
The regulator is probably the Waltham Star regulator. Good design, easy to make fine rating adjustments with.
Thanks for letting us know the outcome.
Enjoy,
Bob