Through-Hull/Ball Valve Thread Mismatch -- Urban Legend?

[Dockhead]

Originally Posted by Wotname

FWIW

I recently got a bunch of irrigation fittings (all BSP). Prompted by this thread, I had a closer look at the threads.

ALL the female threads were straight.
ALL the male threads were tapered.
This were common fittings available anywhere in Australia.

So I next visited the local chandlery and checked a bunch of the marine pipe fittings (SS, bronze and composite). Of course they were BSP and likewise all the female were straight and all males were tapered except the male skin fittings (mushroom style) which were all straight.

Everyone I know uses tape on the threads or a jointing paste or like me, both.

So much for the myth that taper can only go in taper.