In the Nacra 18 Square I had in the 80's, these fore and aft tubes were used to prevent rotation of the front and ream beams. Later, Nacra was able to eliminate the tubes (on the N5.2) by putting fittings inside the end of the beams that screwed into the hull and prevented rotation of the beam. I don't know about the Sol Cat, but this might have been the reason for the fore and aft tube, just like it was on early Nacras.
Ahh so... guess the decks were initially not thick enough to do that, a la Prindle. Always wondered how Nacra's strapped down ROUND crossbeams were "keyed" into the deck.
I'm guessing you quickly get used to "stepping" over the bar on your hands and knees... or while "skooching" over on your buns, lol.
I've found your lengthy feedback on my 18 sq queries over in the F-18 forum, and thank you profusely... this boat seems to have seized me recently, with such intensity that I fear the only sure cure is to purchase one... at least one.
Just a question of how many states I'll have to drive across...
