My stepdad and I are going to try out building our own surfboard. He has a roll of 1.5 CSM Fiberglass but that’s all it says. I can’t really get the information I want anywhere. Can I use this type of fiberglass to build a surfboard?
Hey kid -
I Googled it and found out that 'CSM' = Chopped Strand Mat. Am assuming that '1.5' = weight of the stuff per sq yd.
Light CSM like yours has a place in some composite manufacturing but it is not really suitable for glassing a surfboard. What you do want to use is typically available through any of several retailers who specialize in surfboard materials. Depending on your blank type you should consider at least 4 oz/sq yd plain weave fiberglass with silane finish.
If you are using EPS foam for your blank, you must use epoxy resin. For a urethane type foam blank you can use epoxy or polyester resin.
Same thing though on the resin... be it epoxy or polyester, stick with a standard surfboard quality resin purchased through a surfboard material retailer for best results. The resin formulations they sell have been developed for surfboards and tend to withstand UV exposure better than hardware or boat store stuff.