Problems with stock poly/1.67 Crizal lenses crazing

[optyxxus]

I have been having problems(just recently) with Lenses crazing immediately upon mounting in a new frame. Only poly and 1.67. Full frames, semi rimless, Zyl as well. Mostly in smaller B measurements(32 and below). I have been using the same product and frame styles for multiple years and it is not until recently that the issues have occurred. I understand that the thin CT on stock lenses and "flexing" is probably the issue but where I have been using the same product for a couple of years and never had any issue. Any helpp or input would be appreciated as it has started to get expensive in product cost and customer relation issues.

[theGross1]

I have been having problems(just recently) with Lenses crazing immediately upon mounting in a new frame. Only poly and 1.67. Full frames, semi rimless, Zyl as well. Mostly in smaller B measurements(32 and below). I have been using the same product and frame styles for multiple years and it is not until recently that the issues have occurred. I understand that the thin CT on stock lenses and "flexing" is probably the issue but where I have been using the same product for a couple of years and never had any issue. Any helpp or input would be appreciated as it has started to get expensive in product cost and customer relation issues.

I have/had a similar problem. I found two things that helped. Shortening the A as I found the lenses were coming out long and were flexing as the barrels were closed. The craze marks in those cases are linear. I also had a problem with my edger where the chuck was clamping to hard. Those craze marks were circular and the same size as my chuck pad. On your next medle frame try backing the barrel screw out while watching the lens. I could watch my craze marks lighten and sometimes disappear.

[PRECISIONLAB]

Try inspecting lens throughout the edging process pre/post edging and blocking. After the edging cycle and before deblocking varify AR quality. Inspect again post deblocking and pre mounting..and so on. We run 7E's and use shape 002 which is a 58mm circle pattern to "crib" lens before cutting to shape. As you know sizing is crucial to reduce lens stress when mounted. When deblocking we "twist" block off as opposed to "pulling" off. We also use a hard type block base curve specific and matching right side chuck to apply equal pressure to the front and back of the lens.

Can you list your edging procedures as this may help others advise on this thread