Are there tools for cutting old fasteners (5/16" dia bronze) from the
inside of hulls? If so, please advise what I can use to cut flush to
the inside of the planking. I am adding new frames before hauling to
through fasten with new. My boat has a fiberglass skin and I do not
want to break the skin anymore than needed.

I have been using side cutting disks on a 4" grinder. It works...but
is slow and messy.

It would be great to find a shorter electric or pneumatic hand held to
do the cutting.

thanks for help
marshall