I am currently doing a bottom job on a holiday mansion and was wandering how coarse of sandpaper can be used. I am currently using 80 with an electric random orbital sander.
getting ready to do mine.talk to a guy that use to do boat work from start to finish and rebuilds.he told me to sand outer paint to smooth useing 180.them spray with gelcoat,half the hardener,then wet sand with 1000 grit.hope this helps
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