Hi again. I have been out to the playroom again, and checked four cylinder heads and blind head water-domes. All are threaded 1″x20tpi, repeat 20tpi. All I can think of is that SOME but by no means all are 24tpi like yours and it is worth noting that cycle threads above about half an inch diameter do become erratic in pitch listings, with 20,24,and 26tpi being alternatives, so carefull checking is obviously necessary before attempting to screw in a new hose spigot. Regards. Brian.
