Glad you like the part I made. My first step was to make a replica part; I used a casting sand with a resin binder. I then took my replica part and machined off the flange. Then I made a new flange the size I wanted out of styrofoam and glued this to the base from the replica part. Again I made a sand mold, burned out the styrofoam, and then cast the piece with a standard casting aluminum. The part has worked without any problems.

All of this might be hard to accomplish without the right tools. I am a college student and had access to the casting shop on campus, which made this project take less than an afternoon. Hope this helps explain things.

You must be a brave man to trust duct tape like that.