Hi Richard: After replacing over 200 sets of keytops, I have settled on solvent based contact cement. Water base doesn't hold well which might explain the failures. That doesn't mean there aren't good alternatives, PVC-E works well too, but there's some drying time involved. There are pros and cons to all adhesives, one could go into quite a dissertation on just keytop glues and what form they take i.e., spray, gel, or liquid. Mike Kurta, RPT Chicago Chapter
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