I stumbled on to a little trick a couple of years ago to get rid of the sharp edges. My experience with various types of sand paper and abrasive cloths weren't very positive. I found that rubbing the cut edge with another piece of glass (scrap piece or even a jar or bottle) got rid of the sharpness quickly and with minimal effort. You run it across the edge over the length much like you would use a file. This doesn't give you a bevel, but does render it safe. If building a tank the only edges of concern are the exposed ones such as the top edge and outside vertical corners. As well a Dremel type tool with a cylindrical diamond bit will remove material and you can actually bevel the glass. However, before using the Dremel I would still use the glass. I ran this past a club member who has cut thousands of pieces of glass and build hundreds (perhaps thousands of tanks) and he had never heard of doing this. It does work and I used this method on a bunch of braces I made for some tanks I built.
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