This was going to have a little welding in it, but I changed my mind. I was going to make it out of half inch and build up the top part with weld, but in the end I just whittled it out of 3/4 stock, instead. These are mounts to attach some areo bars to a pair of bicycles.
Started with 3/4" x 2" 6061 T-6 extruded bar.
Carve out one side.
Flip it and do the other side. Bore the holes and profile the part out.
Flip again and drill, tap, clearance, and counterbore a couple of holes. Profile the ends round.
Flip and scoop out the top. Drill and tap a hole.
Here they are mounted to the bars.
Test fitted on some handlebar tubing.
I'll probably give them a nice glass bead blasted finish to smooth out the machining marks. Although first I have to clear some junk away from the bead blast cabinet, and I think fix some air fittings on it. Shop maintenance never ends.