As per some long time ago discussions here the Crossfire 20 built in Sydney late 70s early 80s was "derived" (heh heh) from the Schock Santana 20;
static1.squarespace.com/static/58dbd7fbebbd1a38a556fc15/t/592311842e69cf390a48f956/1495470517633/S20OwnersHandbook.pdf
The www.s20.org website is excellent and has many tips and suggestions for repairs and maintenance, including to rectify some areas of poor initial structural design and manufacture. eg
www.s20.org/santana-20-mast-step-compression
And a grab back of fixes needed to numerous issues as per here;
www.s20.org/general-information-about-s20
Does anyone know if the Sydney built boats designed and manufactured any or most of these out? Appreciate concise advise. For example the mast compression post deforming the hull stringers and keel floors, and forcing a gap between the leading edge of the keel going aft for a bit, doesn't sound very good. Realise they were a light boat - one did well in the Hobart JOG nationals late 70s/early 80s - I remember the series report talking about the design being "very wet...". Stands to reason racing a low freeboard 20footer in Storm Bay squalls.
Thanks in advance.