> The rimless frames I got from Zenni use screws and nuts to hold the lenses to the
> frames. The lenses are not even poly, just the 1.57 index lenses, so I
> am kind of wondering how long I can keep the lenses from breaking or
> shattering. :)
Zenni claims that they only use polycarbonate lenses (http://
zennioptical.com/cart/pages.php?pageid=8).
I got rimless glasses from Zenni, and I swapped lenses a couple of
times between two different rimless frames. I ended up with a crack
between the notch and the screw hole on one lens (probably while
wiggling it off past the nosepiece), but it's still usable. Next time,
I'll move the nosepieces out of the way of the lens removal path
before starting.
It's too bad that CR-39 is not supposed to be suitable for rimless
glasses.