The brass flange was made from a piece cut from an old (irreparable) oxygen regulator. It still needs to be secured. I plan to fasten it with machine screws from underneath. The bottom of the flange has a 1" diameter pilot that sits in a counter-bore, so it's thick enough there to drill and tap.
I wanted to get this part done before I did any finish prep, since there were more holes to drill. I drilled and tapped the bottom of the flange for two #10-24 stainless steel screws, then drilled matching holes in a ½" brass washer.
The screws are #10-24 x 1¼" SS socket-head, with SS lock washers. I used socket-head screws because the heads are so close to the ½" threaded rod. A screw with a larger diameter head probably wouldn't clear.
Holes for these screws were drilled in the wood, running parallel to the hole for the elevator. The flange sits in a counterbore that holds it securely in position so there is no side-stress on the screws.
It turned out to be more complicated than I intended, but it's unique!
For now, the brass acorn nut is the 'grip' for the SS elevator screw. The screw turns easily, maybe a little too easily but I can tighten it up with rubber o-ring if necessary.
I plan to eventually replace the acorn nut with this brass knob from an old cutting torch. It'll need a little modification to fit onto the ½" threaded rod, and a really good cleaning, but I think it will make a fine grip when it's done.
It measures 1.215" from tip to tip.
That will have to wait, priority now is to get some protective finish on the wood, so it can cure while I practice for my "walk the walk" entry. I wanted to shoot the actual match from this sled if at all possible (there will probably be spectators), and time is running out.
