I am building a rear rack for a Townie Electra with a front wheel electric assist (
link to original build ). I have already broken two bought aluminum racks due to the 22 lb battery, so I am brazing a steel one together.
The problem is the connection to the seat stay. The original frame boss on the right side has pulled out due to the weight on the rack.
I am thinking of 'wrapping' this part of the frame with an aluminum band/clamp, and bolt it to a support beam from the rack. I am also thinking of adding to additional support from the rack to the seat stays below the brakes with P-clips.

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I am concerned about the hole left from the pulled out boss on the seat stay. Should I try to fill it with epoxy or wrap it with fiberglass, or just leave it alone? Any comments about the planned supports or their placement?
Thanks for your time.