Hold onto your glass object with one hand. You can try placing it inside a clamp, but it is more likely to crack the edge of your glass. Only use this method if you can safely grasp the glass object without coming into contact with the sanding bit.
There are hand stones, (cheap), that you can use to quickly grind off the edges of glass. They can be found at most SG suppliers. There are also diamond sponge sanders for coldworking, by 3M, (expensive! think grinder bit!), that come in varying grits. Finishing A Ground Edge - Beauty Salon - Stained. How to sand food safe glass by hand.
How can we cut mirror or glass in a desired shape? Video shows tips on finishing a cut glass bottle by using rotary sanding drums to smooth the edges. I am an artist and glass happens to be one of my favorite mediums. I have used a number of different grinding methods to smooth edges for glass : wet belt, table-top grinder, diamond hand laps, and the dremel.
If glass is something you want to make more than an occasional hobby, I definitely suggest purchasing a small tabletop grinder. As you can see one tried gluing sandpaper down and getting it wet and running the lip of the glass along it. Another used a hand sander.
My glass company seamed all the edges which is the technical glass term for sanding the edges.


