I recently had a rather small piece of glass to glue to another piece of glass and found out an easy way to keep it in place while it dried. Take a wad of play dough or modeling clay, press it over the piece to anchor it in place. When dried, just lift it off.
By Jim from W. Hollywood, CA
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I have used several glues to glue glass to glass. I started with E-6000, but found that the tube of glue was useless after 2 or 3 uses. It wouldn't bond anything anymore.