a good tip is to try several items before making it your choice. the activity sheets vary in difficulty so you can easily differentiate your lessons. that is how it does this. > hell, then the temperature and pressure will drop until hell freezes over. the machine can also record the exact position and pressure required for each bending operation to allow the operator to achieve a perfect 90 degree bend across a variety of operations on the part. the more people that get involved the more people we can help. 