Just wondering where you got the "no slackiness" plastic hinges that you used in the binding router jig? Been googling for a while now and only found these type

Ive built your binding jig with metal hinges and there's too much slop in it ( cheesy hinges). A test cut jumps and binds due to the slop in the hinges, which is freaking me out after the last mishap routing the slot for the end graft! I've spent some time re installing them at a slight angle to close up the gaps, but hasn't really made much difference.
Cheers