PVC Roller Reefing Furler
That's right - a Reefable roller furling system made from standard schedule 40 PVC at a cost of under $20!! I wish I could take credit for this design, but the credit belongs to Greg Cowan, owner of Com-Pac 16 Fat Bouy. Specific instructions can be found on the Com-Pac Owners Association website (http://www.com-pacowners.com/).
Improvising on some of the modifications made to this system by others, I came up with a different design for the furler spool. I use two 4 inch round electrical box covers with 1/2" NPT hole in the middle. The shaft of the spool is made out of a 1/2" NPTx3" pipe nipple. When threaded through the holes in the round plates, the nipple extends far enough through the plate to attach a 1/2" PVC thread-to-coupler on top and a 1/2" PVC threaded cap on the bottom. The furling system rests on a stainless steel washer and cable stop, which in turn rest on top of the forestay turnbuckel.
The system works extremely well under sail. As you can see here, as long as you pay careful attention to the distance between jib hanks when you build the furling tube, the foresail can be tensioned top and bottom so that its luff doesn't scallop. The genoa can be furled in or out, or reefed to reduce foresail area.
I also built a set of "twing" lines to ajust the lead angle of the genoa sheet depending on wind speed and size of the reefed foresail. As you can see here, the twing lines run through the jib cam-cleat (forward) and the genoa cam-cleat (aft). The block used to lead the geona sheet can then be adjusted fore or aft in order to give the genoa the proper sail shape - similar to a genoa track, but without having to drill holes and mount hardware on the coamings of my boat.