I totally agree with the other comments. When I teach my new students to score the glass on a drawn line, I always tell them not to look at the cutter but a few inches ahead of it. Think of when you learned to catch a ball. You look at the ball, not your hands. Same principal applies. I always teach my new students to score a straight line without a straight edge ruler. It works evey time.
The way you control the cutter is to hold it as close to the cutting wheel as possible. Do not hold the cutter in the center of the handle or the back. Sometimes when I am cutting a textured piece of glass I actually hold the handle with my thumb and pointer finger gripping the metal above the wheel. Total control.
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