spiral cracks

[Guest]

While cleaning the hull of my GRP E-Boat today I noticed two cracks. One was roughly circular, approximately the size of an old 50p piece; the other was about 20 per cent larger and spreading into a spiral. Neither crack showed any give or movement when significant pressure was applied with full bodyweight behind two thumbs. The boat has been off the water on its trailer for three years and I don't think anything has hit it. Is this a cause for alarm?
Thanks in advance
Colin Geddie

 

[Guest]

You might have a slight void behind your gelcoat i.e the gelcoat is not attached to the laminate which leaves it unsupported and more prone to crazing. If they are well above the waterline I can't see they will be much of a problem.

 

[Guest]

I wouldnt worry abut them too much, just check them every now and again to see if they are becoming larger or deeper etc.
Richard