With both the shoulder press and the chest press machines (normal or C-curve), I feel like I'm just training my triceps. They're all I feel. Now, it's got to be posture, since my shoulders are a lot weaker than my triceps and I doubt my triceps would have trouble lifting... I won't give the exact weight to spare myself the embarrassment. But I've tried adjusting my seating height, but that didn't make a difference at all. I've also tried experimenting with different ways of gripping the bar, but I haven't found much difference there either. Still, it could be in there.
Any tips, possible solutions, things that might help, how you do the exercises, anything?