Photos of one of my detachable keels are in an album "Keel". The 6mm
studding goes through a metal tube in the hull 21.5 inches back from
the stem. This particular keel has loose lead shot (sold in gun shops)
in the bottom of it. 7 1/8th" front to back across the top. Max depth
(in water) 7 1/4".Max dimensions for the keel bulb are:- bulb length
11 1/4", width 2 1/2", height 2 3/4" (NB this is where ALL of the
weight is carried).