It sounds obvious, but you need to connect that swivel & drum to your bridals & forestay. If your bridals terminate with forks,(as in Daves link), AND you have that kind of drum you are golden. If you are using the Harken drum, you will need to pick up a triangle plate such as this
.
If your bridals end in thimbles you need to connect the bow shackle around the thimbles to the fork at the bottom of the drum. Most shackles are not wide enough to span the drums fork. However you rig it, you want the load evenly split between the two sides of the fork.
At the top end, you cannot directly connect the swivel to the bow shackle that also holds the shrouds. The simplest is a short tang such as this
Note that one hole is larger, to allow the shackle end to pass through.
Don't get to hung up on an exact measurement for your new forestay. Many people incorporate a 10 hole adjuster on top of the drum. This allows for the stay being an inch or more to long, mast rake, provides an easy mount for your Davis wind indicator, clam cleat, etc.
There is no single "perfect" solution. What is best for a trailer sailor who races every week may not be best for one who keeps the mast up all year. Some simply tie the tack with a bit of line, & tie off the halyard to maintain jib tension.I prefer to hold tension with a clam cleat as my boats sit on seadoo lifts & the water is deep enough that is is awkward to reach up & tie anything.
I have seen small blocks rigged so as to give a 3:1 purchase, personally I feel that is hardware overkill. I currently am experimenting with a single block at the drum, leading jib halyard to the front beam, so I could tension & de tension the jib from the tramp. This really is not any advantage if you rig your boat on the beach, I found it useful as my boat never comes on land til season end. It was easier than placing a 2x6 across the bows at the dock, then walking out to tension the jib. Take all suggestions, but in the end, do what works for your individual situation.
Whatever you do, remember to tape the ringdings at the top end. Last year my mainsail halyard snagged a ringding on the swivel, & left it as only a bent piece of wire. Lose that pin & you lose the mast.
When leaving your boat for ANY length of time with the jib furled, use a safety, so it can't come unfurled. I use the original clam cleat on the mast for the furling line. To safety it, I wrap the tail around the mast & tie it. When I leave the boat for the night, I also run a thin line through the tack grommet, wrap it around the jib & tie. It's redundant, I know, but I sleep better in Hong Kong when I see storms on Ontario radar.
If your jib comes loose in a squall it will turn into dental floss. I don't personally know this fact, but Andrew(MN3) does
Finally, if you leave the jib on, as I do, spend $150 & have a sail maker sew a UV strip to the leech of the sail.
While they are at it, have them pull the jib battens & replace with double length battens, set at roughly the same angle as your forestay. Without those two small battens (talking Nacra here) the leech tends to vibrate & flog, especially when pinching. If the battens are left perpendicular to the mast, it furls like shiit.
I have been meaning to create a tech album on this subject for 2 years now. Many people here helped me with my first conversion. I'll quickly make an album with a bunch of basic photos, as that says more than pages of writing. I'll get to the captions later, I promise.
Edited by Edchris177 on Jul 13, 2012 - 08:52 PM.
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Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
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