A simple cheap alternative would be to make a case back from a CD (Compact Disc)
I have a habit of stringing up CD's in the garden. After they have weathered the coating comes off and they are clear but not as transparent as a watch crystal. Also the ones I have had are 2 part laminates which easily separate after weathering. I have used these in the past for emergency crystals in cheap watches.
In this case you could use a new CD. Cut out a circle which fits tightly into the case. Cut another circle which fits over and to the overall diameter of the case and glue the 2 together. Alternatively just cut a circle which fits the overall diameter of the case and glue it on but glue it all around so to seal it. Trim if necessary with a file, sandpaper etc.
It should not scuff up as quickly as a crystal. I use scissors to cut after the CD has delaminated ie one half but I use my scroll saw to cut a full thickness CD
I appreciate very mutch all the good help I have got during this watch repair! But that is why I usual stick to mechanical watches, and that this was just for a really good friend. And that I usually dont do quartz. Thanks to ya all... :-)
oldhippy, when you grow up with the poisonous creepy crawlies you learn to know what to watch out for and respect your surroundings. We've had several Tiger Snakes, that we've known of, in our yard over the last 18 years, which isn't bad considering we back onto a creek. And that same creek brings us wallabies and water birds, so that's a definite bonus. Too much sun exposure is more of a worry, and killer, in this country
ecodec, It's the making of things that drives me
Hey Geo, I didn't have the brass for it so... A friend of ours gave me the, then rusty, bobbin winder for an antique sewing machine to turn into the drive wheel. I drilled a shallow hole in the bottom of each foot and inserted a crepe rubber plug that just protrudes by less than a mm. This stops it from moving in use, while not making it 'wiggly' on the rubber.
Here's a view from the other side showing the adjuster slot for the belt tension and, if you look closely, you can see a nail that goes through both clamp jaws (tight in one and free in the other) that I hook the 'tail' of the turns under. This makes the turns very secure, even before tightening the two wing nuts on the clamp.
Have a good night guys.