Re: epoxy barrier coat sun exposure how long is too long?
The one job I refused to do when I worked in a boat yard was stripping bottoms. Couldn't pay me enough to make it worth the pain of holding a sander up above my head all day.
There are a few, very few highly skilled guys that can strip a boat with a hand planer. Unless you have a few bottoms to ruin while learning how don't try it, but it is the best way to strip a boat.
These days though I doubt there is a yard anywhere that is using sandpaper to remove the bulk of old bottom paint. It is massively labor intensive, an environmental nightmare, and well known to cause health problems to anyone who breathes in the dust (remember bottom paint was designed to kill living things). At least around here most yards wont even allow you to sand your own bottom, let alone do it themselves.
If you have to strip the boat yourself chemical strippers are the way to go. They are much easier to clean up since the residue can be scraped into a bucket, and take a fraction of the work. Soda blasting is easier, and cleaner, but the machines are rarely rented.
Figure about $40/foot for chemical or soda blasting. For sanding, well again I wouldn't consider it so I have no idea. But it should be pretty cheap since all you are buying is sand paper.
If you happen