Having measured the dia of the opening in a watch bezel how much extra should be allowed to obtain the correct fit.

Bezels and crystals are rarely, if ever perfectly round. Hand fitting by finding the largest and smallest diameters of the bezel and crystal is often necessary. In the case of hunter crystals, as you know they break very easily so without practice expect to go thru several and be very careful you don't wind up with stitches in the process.

Thanks a lot Roger.

I'll get spares to hand and warn the local emergency services that they may be needed Ha Ha.

Mike,

This is a hit and miss proposition at best. Even with great measurements... what the guy on the other end measures may not add up.

Trying to order by Ligne size... 17-5/16... is a crap shoot at best... the tolerances on labeled sizes can be off by enough for the crystal to actually measure for the next larger or smaller size.

When I needed crystals, I would order one at $8-$15 a shot... it would come in a week later, too big or too small... I would order another.. it would be off the other direction... generally three tries and three weeks later... I might have a crystal that was close enough I could glue it in.

I got so frustrated, I dropped well over $1000 on crystals in mixed lots at $.75-$1.00/crystal... so many that I had to buy my own crystal cabinet and spent many hours with my girl friend measuring, relabeling and sorting them in to the cabinet.

It saves me on average, $25.00 and two weeks time over ordering on line. I figure that works out to 4 watches per $100... and only 40 replaced crystals to return my investment... not to mention the turn around time.

Several people here offer crystal replacement services at a very reasonable price considering the alternatives.