my first
boat was a home built Roberts 38. Like one of the previous posters I welded steel threaded nipples to the
hull. At that time, early 80's, I can't
recall that marelon valves were available, so I trundled down to a local pvc supplier and purchased a variety of different size pvc ball valves and hose fittings. I can only
recall that the valve bodies were grey and the handles were a T-top variety in red. The valve handle could only be turned through 90 degrees. These were inserted onto the threaded steel nipples with some thread tape.
In the 15 some years I sailed that
boat I never had a lick of problems with them. Not once, not ever !! The steel nipples, schedule 40, had been sand blasted and painted with a zinc chromate
paint, so the valves were a little difficult to install over the painted threads, but I got them all on. Those were pvc valves.....I believe the grey color indicated some or other pressure rating, as they were quite thick.
Regardless, while bronze is undoubtably stronger than pvc, I would challenge anyone to break one of those pvc valves.
Several other pipe runs inside my boat, ie, the
cockpit drains, were your regular pvc pipes which I glued together with pipe glue ( the blue stuff). Likewise, not a
single problem ever!
Again, each to his own, but I had good experience with plastic.