I made a leg press that mounts to my squat rack......it's basically a cross member at the back with an arm bolted to it (single bolt for a pivot), a foot plate at the end of the arm, and a couple of pipes on the foot plate to load weights on. I can't decide if using it is tweaking my knees. I'm lying on my back on a slightly slanted bench about 6" off the floor, and I'm pressing the weight up, but the issue I think I have is the fact that the foot plate runs on an arc, so the angle of my feet changes as the weight goes up (calf and foot don't remain perpendicular). Also, at the bottom I think my knees get splayed out because the stop is set too low. I don't think the foot angle is an issue, and I think I should shorten the ROM so that I can bring my knees to my chest so that my legs remain perpendicular to the foot plate throughout the movement. Am I right? Any other suggestions?