I wasn't happy with the state of the lacing on my surface grinder's leather drive belt, or the fact that it was stretched to the end of the adjustment (and there's a lot of adjustment) so I decided to try my hand at splicing the belt and if that didn't work I'd buy a new composite one.
I knew nothing about belt splicing so I checked out a few websites and a couple of youtube vids and made myself a plan. By backing off all the adjustment I got a healthy 100mm/4" over-lap on the belt ends. The belt is a 3/16" (5mm) thick leather item and was in ok condition other than the dodgy clipper lace.
I got a piece of scrap flat bar that was a good match for the belt width. Actually I stacked three of them and sandwiched them between two pieces of scrap plate. I set the flat bar to slope down from the top edge of the plate by 5mm over 100mm and clamped it with two g-clamps (actually I tacked it with a few small welds too but that's not necessary). Then I put the belt in the jig and used a 5" grinder with a 36 grit sanding disk to taper the end from full thickness down to about 1mm thick at the end. After that I took a file and filed a step in the jig (and the belt) and generally cleaned it up.
After doing the second side I took some normal evo-stik contact adhesive (red tube with IMPACT on it) and slathered a goodly amount on one side of the belt splice then squidged the other side all over it to give them both a generous coat and try to soak some in a bit. I held it like that for about 20 seconds then slid them apart and scraped away the excess with a razor blade. After it went tacky I put the two halves together and clamped it up with a bit of scrap ally plate for about 18 hrs.
