Which is better, i.e., ease of application, durability, scuff/damage resistant, repair: fiberglass with resin or epoxy with graphite?
A combination of both, triaxial cloth with epoxy for abrasion resistance, graphite may or may not slide easily on rocks.
What I have found is my boat built with these components does slide over rocks and I can observe scratches in the graphite, most of which are very shallow. Since there is water pushing on my boat I don't have a method to discern whether or not there is less friction than without graphite.
I did suffer a broken out chunk of fiberglass, epoxy and graphite along / behind one of the chine caps. Obviously a hit on a rock probably suffered while traveling with my boat perpendicular to the current.
Repair was easy, mixed a small batch of epoxy, slathered it in and let it cure. The river will sand it flat. You could choose to add graphite if desired.
Epoxy by itself is not very tough,put some on a piece of ply let cure add some weights on top and drag it down a gravel road behind your truck.The epoxy will be gone in a short distance.What makes it tougher or harder to sand is dense fillers like West 404 high density filler.
Graphite by nature is slippery but not very durable so we wet out our glass with epoxy when tacky we fill the weave with a thickened mix thats hard to sand this fills the weave so you get a flat smooth surface then paint on a couple of coats of graphite.So you get a nice shinny black bottom thats slippery and tough.Repairs are easy because the graphite isn't in the glass its on top.
That might be the best explanation of our bottom protection yet.
Thanks. That is a great solution.
thanks for the input on the durable bottom finish,I'm just getting back into working on the boat from a long winter here in Wisconsin. next step is glassing the bottom and was just looking for other than just graphite in the top coats,just bought some 404.