RE: severne sails tack pully?
Hi Steve C,
Yes, when the axis of the upper and lower "axles" are the same, it's pretty easy to thread a downhaul line. Just think of a large industrial crane. The vast majority of them simply thread the wire rope around the sheaves starting at one side and working toward the other and the upper and lower sheave are on axles that are the same axis (across the front of the crane).
So, I can see, after years of doing it the NP/Bill Hansen way (I never could figure out those diagrams very well) changing to the "Quick 6" with the upper and lower axles running fore and aft could be a challenge until you figure out that it's a simple "start at the sheave nearest the mast, on both upper and lower sheaves and simply wind the line around them like they were one large diameter tube.
I use alot of both types of bases, but my sails are all Sailworks with a fore/aft tack block, so I get to rig a few of each type of base at demos. I got to rig the new Severne 7.5 m2 "Glide" this morning on a NP base and an HPL base so I'd remember how to use parallel axles that run across the board (just like the crane).
Keeps me on my toes!