A couple of years ago I had some gates fitted, each about 6' by 6'. They seemed well made with cross pieces, pegged, etc. However, one has sagged by about 1/2" or so and rubs against the other when closed. The hinges used are v similar to http://www.screwfix.com/prods/75120...e-Hinge-Packs-Spelter-Galvanised-50x630x165mm There doen't seem to be any adjustment in the hinge itself; how can I adjust or rehang the gate? (The builder has since passed away from the big C. )