Glass Drilling 101
Actually this turned out to be way easier than I thought. Once you get past the fear of the glass breaking when you hear the drill bit grinding thru, you're OK. Total time to drill the hole...5 mins.
I got everything ready. Diamond bit from Ebay ($6), plumbers putty ($1.99) and bulkhead from LFS
($10). I layed the flange where I wanted the hole and just outlined it so I knew where to drill.
I made a dam with the putty and filled it about 1/2 way with water. I also read that using foiled duct tape on the back will help prevent chipping. In my case, it was a waste. The hole didn't go thru exactly straight and when the bit went thru on the one edge first, the tape fell off when all the water drained thru the opening.
Here we are about 1/2 way thru. The water was white from the ground up glass. I mopped up the water but you can still see some of the white glass grindings.
And the finished hole with the bulkhead in place.
This was really easy and fast. What I did learn was when starting the hole, drill it at the highest speed you can. I used a Craftsman cordless drill and tried going slow at first, but the bit just slid around. I pulled the trigger full speed and even tho it got pretty loud with the grinding noise, the bit caught and away it went. I stopped about 1/2 way to take a pic. I wouldn't do that again either as it was scary restarting the hole. Once you start, keep the drill full speed and go until you are thru the glass. I used virtually no pressure on the drill. I just let it go on it's own.