Is there anyone out there who can take a 3D model of a 1 piece flange and CNC it out of brass? I modeled a 1 piece flange to the dimensions of Golden Gate/Saga flanges, and instead of the standard holes, I made it as similar as I could to Rob McCoury's banjo, the one his father in law made, in appearance. I realize Rob's is a tube and plate design but still one piece, but it is so much easier for me to build a banjo with a standard 1 piece flange.
What you may want to do is look for a company that performs water jet cutting in your area. You supply the CAD or some can design from a photo(s). Custom car and motorcycle makers use these companies for one-off designs.
Another consideration is 3D printed sand mold casting which after design and printing it is then shipped to a foundry. There you can have a metal formula made, poured, and finished by yourself or possibly the foundry.
Out of the two, the water jet would be the cheapest. 3D sand casting would involve shipping a VERY heavy casting which would add up the cost quickly.
Harry Lane milled his flanges from solid brass billet. Some were very thick and he started reducing the bulk in later years.
Steve Ryan makes them & last time I talked to him he was going to make more. He did round holes in a couple of mine instead of the Gibby style.
Contact Chris Sorenson at CompanionBanjo. He posted within the past few months about new flanges from his company and the possibility that he could offer custom hole shapes.
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