As you have probably observed, leather is not the material of choice. It will not hold up to the flexing like Vellum. However, to be anal/nitpicky, Vellum is Leather! As for your choice of glue, (ie white glue), I would not recommend White glue. It goes through too many phases to be consistent, IMHO If you are looking for "flexibility" in the glue, then White Glue, Specifically SOBO, is the one of choice. As to where to put it: it should be in the slot only, (and just a little bit). It should NEVER be on that area that is the "joint" and bends. Having said all of that, I know that many manufacturers did in fact use various types of leather, (ie tanned whatever), for certain pivot points. This, I think, was the weakest link in their manufacturing. I personally go by the philosophy that "I only want to fix this sucker ONCE", so I use vellum, which is better for the job you have described. (Again, just MHO) Regards, Joe Garrett, RPT, (Oregon)
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