The normal tension at which your 36PET-CP-BOPET film is run in our coating lines is 22-26 Kg and this is the line tension. There is no need to measure the tension on the sides of the film in the line because when the variance in tension between the sides is small, we are able to run the film through the coating line without major issues. However, when the slack band is as prominent as to make the reel non-runnable, like the ones we are seeing in this batch, we visually see the reel wavering on the slack side when it travels between cylinders. Our operators always attempt to eliminate the problem by increasing the tension in the line as this stretches the non-slack side of the film and increases the tension on the slack side. This method eliminates slack band issues in the majority of the cases when the film is 12-23PET because these thinner films stretch more and it is feasible to achieve the adequate tension for run-ability on the slack side. Unfortunately, with 36PET being a thicker film we can only increase the tension to a certain degree, because they do not stretch as much as the 12-23PET.