So this is a known issue with both Indy Fab and Fat City. The rust due to IF using blind tubing.
There is no weep hole between the seat tube and the BB shell. We drilled holes thru the BB shell into the
seat tube in my old shop for this reason.
Indy Fab instructs owners to remove the seat post every few months to air out the seat tube, and
doing the same after every time it rains.
Somewhat related, this came up in my reddit today:
https://www.reddit.com/r/bikewrench/comments/1hc9r02/custom_indyfab_frame_cracks_and_if_and_shop_claim/
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