After my failed attempt to cut a mirror, I got a hold of 2 more and tried again (after watching some videos on the subject and buying a better scoring tool.) I successfully cut them both. One I cut into 7 pieces so I am sure it wasn’t just dumb luck. Here are some important things I learned about how to cut a mirror.
Cut a Mirror
Amazon affiliate links: Fletcher Terry 01-711 Fluid Glass Cutter, Fletcher Terry 09-541 Fluid Glass Cutter
2. You need oil. Either on the mirror or on the scoring wheel or both. I think you can use any kind of oil, sewing machine, cooking…not sure. I just bought the oil that had the same brand name and was meant to be used with my new cutter.
3. Clamp your straight edge down so it doesn’t wiggle around. You need a firm guide to follow in order to score properly.
So there you go. It is possible to cut a builder’s mirror.
There was a little chipping right along the edge but nothing a 1/4″ lip on a frame won’t hide so I’m totally happy. It was actually quite fun!