I know this is an old thread, and likely the OP has figured out the answer, but since I own one of these rare boats, I thought I would add (for the record):
Yes, Rafiki-37s have cored hulls below the water
line down to a foot or two above where the keel
The material is Airex (not balsa). I have a copy of the original blueprints, and have replaced a thru hull
, so I know exactly what it looks like. The core
is a surprisingly (to me) thin layer, sandwiched in a thick fibreglass laminate. It is very well constructed and built. I have never heard of any hull
problems associated with Rafikis.