I've been searching and I'm still unsure about all this... yes the bending works with simple middle bends and iPhone 5's . But the iPhone 6 with tiny micro warps not so sure. I'm talking corners and multiple bends and twists. I'm amazed there is no tool that clamps the whole frame into a solid mould. I'm actually thinking i might make myself one after getting so many new frames with slight defects!
Well I'm told the sponge on these parts are not necessary. Though i do wonder about how loose they can be... I'm moving on to checking for any slight bends but i have lots if frames so it seems unlikely.
I know this is old but I'm having a nightmare ... same problem but i have 7 screens 8 heat shields and 5 frames and 3 iPhone 6 phones. All have slightly different problems but all slightly do not fit ... argh! They are from many different sources so surely they can't all be duff! The screens mostly seem to fit without anything on them but at the final fitting something always goes wrong! Tried almost every combo of testing now... what could it be? One thing i thought of was... do you need the sponge bits on the side clamps for the screen to hold properly and were do you buy them? Tnx