I'm having a ton of difficulty with this particular frame I attempted adjustments on twice; I'm entirely sure they're acetate. I have tried using the heater as well as the hot box and even leaving them in for longer segments than I normally would, and they're not shifting at all. They feel slightly malleable but when I actually try to move them, all I get is almost resistance and creaking of the stem inside. This particular pair was transparent so I could see the stem in there as well and kind of saw the tip of it moving inside the acetate which I guess is where the creaking sound is coming from.

I heated the bridge a little to try to open that up since I couldn't get the more drastic bend out of the temples, and the bridge moved slightly more, but wouldn't hold it's new shape.

I had this issue one other time that was a pair of Kate Spade sunglasses for a client and I'm sure they were acetate as well and same problem, nothing moved, and even trying made the stem squeak inside upon opening or closing the temples from there on out.

Just wondering if this a particular kind of acetate or something I'm not aware of happening, because it's pretty baffling to me. I've been in the industry for a little over a year and adjusted enough to have seen a variety but this is stumping me.

Thanks so much!