I'm building my own rack. I ordered 4" heat tape, and they sent 3". I'm wondering if that 1" is going to make a big difference. I'm going to be using 6qt tubs with newsprint as a subtrate. So I want to know if it will make that much of a difference that I should send it back and have to wait for the 4". Or will the 3" still work, and to use it.