Marblehead keel layup

Hi Guys,

Is there anyone out there is RC Sailing Land who can tell me what is the correct carbon cloth weights to layup a Marblehead keel that will end up between 150 grams ( the lightest I’ve seen for sale) and 240 grams (which seems to be average)? It has to be stiff as.

I’ve got a 2 piece mold already. IOM keels I’ve laid up in the past have been usually heavy (around 170 grams) and lack a bit of stiffness. So it appears that weight of the finished article has no bearing on stiffness, even when one is very careful about resin quantity’s.

Any input would be gratefully accepted
Thanks in advance

Gold Coast