Look at the difference between the sanded platform and the weathered platform. A big difference!
To the left is a shot of the stainless steel all thread rod that goes through the platform. You can see I cleaned up the lower shorter piece. I used a stainless steel brush on it. I ended up chucking the rod in my drill press and just held the brush up to it as the rod spun around. It worked nice! I also chased the threads for the first few inches on each end just in case.