Glass cutter holder

I've wanted to transform a bottle into a glass cup but I had a problem, using the glass cutter by hand and rotating the bottle would be impossible to get a clear and clean cut. ith this problem I developed a tiny cap to put the glass cutter in,and make it stable while cutting. As seen in the images I used a plastic cup to give the height I wanted for my glass cup, and putted the holder on top. With now the tool stable, I was able to cut the bottle, and turn it into an aesthetic glass.