I have a base metal case that I can't get open.

I tried, gently, to wedge something beteen the case and back but it doesn't split. Therefore, I believe it is one that has screw on back and crystal bezel.I tried a non-slip rubber jar lid opening to no avail.

Does anyone have some tips to share?

I don't know if you have one or not but since I bought one of those gushy rubber balls I haven't had a case I couldn't open with it. Before I got it I had tried all the other methods I could find.

I think I bought mine from Otto Frei but I see them on ebay too. They are actually just a small air filled ball about the size of a tennis ball & are made of the same vinyl as children's toy balls I see in the super market. It is the 1st & only thing I reach for when I have a stubborn case.

Tom

Thanks Tom, I don't have one of those balls. I guess I will have to start looking for one.

Hi Ernie, there is posting here in the helping hands section for this subject, it involves super gluing a nut to the case back, and using a wrench to turn the nut. I have used this method successfully a couple of times.

Thanks Gary, I will try that too.

But how do you get the lens bezel off?

Ernie, if it's an empty case, you might try a little heat, from a hair dryer, just a thought.

The case houses a swiss watch with the name Calvert on the dial. It says it is 17 jewels. It runs but gains time. The case has an engraving of a train on the back cover.

Here is the back cover.

There are some good, cheap rubber case openers using the "suction and twist' principle made for stubborn watch cases. (Maybe on Findingking.com.) Sometimes a damp, dish towel or face cloth will provide the friction you need.
Finally, if you have to superglue a nut to the case, I understand that finger polish remover will dissolve the glue. Never tried this myself.
Whatever you do that works, I would like to know what method eventually works for you!
Mike

Ernie, I have had trouble in the past opening watch cases also and I found that by putting on rubber gloves, like medical gloves, I can get most any case to unscrew....the rubber gloves really give you traction....

Regards,

Jerry

Success: The cover is off. Thank you to everyone who offered helps. I appreciate each one of you!

I tried rubber gloves, I tried a rubber used for opening jar lids, I tried the non-slip shelf liners for campers and tool boxes. I could not get enough grip to loosen the cover.

Finally I super glued on a 1" nut to gain as much surface grip and leverage as I could. I had to use a lot of leverage with a 1" wrench. Just about the time I thought I was using enough leverage that the super glue was going to break loose the cover unscrewed.

I then used acetone to remove the super glued nut and clean the glue off the cover.

Here is a photo of the Delmont Watch Company Movement that was hiding inside. It is now happily ticking away on my desk and keeping time. However the regulator is way out of position.

I do need to find a second hand.

Ernie, I think on that particular case, the bezel and back snap on and off. Look for an indentation or notch where you can use a case opening tool or knife to pry them off.

Way to go Ernie! I never knew anybody who actually tried the nut and superglue method!
M.