Originally Posted by SuperC
I had thought about using the seat tube bottle holder holes with a curved piece to match the tube curve, but did not think about using the front down tube as well.
Using the front water bottle bosses adds stability and keeps the derailleur and its mount from flexing and twisting during shifting and during riding. Another couple of posts referred to soldering aluminum with a special rod and a common MAPP gas or propane torch. Bernzomatic makes a very similar rod available at Home Depot. If you wanted to save on weight and make a mounting bracket from aluminum, this would be something to try.
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