On cylinder rods used for pins, remember cylinder rods are generally 10/45 steel, not hardened but the chrome plating is what gives cylinder rods their longevity. The steel *can* be hardened, if you've got a big enough torch. I built a backhoe attachment years ago and made my own hardened pins and bushings. I picked up an old kiln, about 3ft in diameter that someone had thrown out and made up the pins and bushings on a lathe. Then case hardened them using a product that MSC company sells, I believe it is called Kasenit (?) I can't be sure of the spelling, it's been 20 yrs.. It worked great. I know the dealer prices are an absolute rip off.