All.... my modus operandi was to keep this simple. My locking knob protrudes ever so slightly to bind against the sliding arm. (See the photo. I removed the sliding arm so you can see the maximum screw protrusion) Will it dent. It hasn't yet but likely over time. I don't over tighten. Just enough to clamp it. You get a feel for it. It will be a long long time, if ever, that I would have to replace the arm. It's fast enough to just make another. Like I said....I wanted to keep it simple.
