I was mowing near a railroad with my Exmark 36" fixed deck and I hit some sort of thick metal that bent one of my blades. I ordered these blades from mowmore.com. They are heavy duty high lifts, .240" thick. They are actually a little shorter than any of my other blades for the same mower. When I put the factory blades (a tad longer) on the mower , one of the blades hits the back of the inside of the deck. What do you think is wrong? Bent shaft? Did I mess up the deck somehow?