Have noticed a crack in the fibreglass appear where the rear of centreboard case connects to lateral strengthening ribs. Has grown progressively over last three trips out, not sure if from sailing or trailering.. Any ideas on what may cause a crack to appear in this location, and any repair ideas would be greatly appreciated.
It is a long time since I saw that form of construction in the 24s, as it was only used in the first 100 or so boats and would go back to 1974-5.
The strength was all in the glass laminate covering the foam frame and is easily fixed. Would suggest you grind back the old flow coat to bare glass within 10cm of the split and apply one layer of Matt followed by woven ravings and Matt using an Epoxy resin.
While you are at it you could do the same to the other side just to make sure it doesn't happen there as well.
The cause was most likely a trailer roller a little too high in that vicinity, or the rear roller taking the whole weight of the boat when launching or retrieving the boat.