What I do now, and it has helped me is to feed enough vinyl (that you will need to cut design) all the way through. Then I make sure it is straight and then clamp down. Then I turn on the cutter and it will pull the vinyl back through to the starting position. By doing that it seems to not run off at all on longer runs. Before I did that the tension from the roll sometimes caused it to pull it off line a little when the cutter does that quick jerking it does to relocate to another position. If it stays straight when first aligning when cutter is started, it seems to work just fine while cutting.