I'm a beginner-intermediate leatherworker. I have a very good swivel knife (Barry King) and sharp blades. However, when I'm making my cuts in tight curves in Sheridan patterns, the leather tears in spots. Not large tears, just tears that appear as ragged edges instead of the clean, tight lines we're after. Am I using too much pressure in the curves, or am I holding the knife at a bad angle, or am I not swiveling the knife correctly, or making some other mistake? If my description of the problem is too vague, then please give tips on smooth swivel knife cuts in tight curves. Thanks a bunch.