attaching spreader to stay

[arch007]

I am restoring a cape dory 28.

I took off the spreaders and removed the seizing wire attaching the spreaders to the stays.

My questions are:

1. After attaching the spreader to the stay is it enough to make sure the attachment is loose enough so
when the mast is lifted the spreader will find the coorect position on the stay ? In other
words HOW do I ensure the angles of the spreader stay attachment is correct ?

2. Does anyone have any diagrams or instructions on how to wire the spreader stay attachment ?

Thanks,

arch

[Bill Goldsmith]

This is how I do it, I am not saying it is gospel, but it works for me.

The goal of seizing the shroud to the spreader is to prevent any slippage. You want the spreaders to cant slightly upwards, to approximately bisect the angle. If the seizing is loose, then over time the spreader may slip down the shroud when tacking varies the load on the shroud.

My method is, with the mast horizontal on sawhorses, to pull the shroud hand tight and give the spreader a little upwards tilt and seize it there, trying to get the two spreaders even. Once the mast is stepped and the shrouds tightened, there is a little stretch in the stranded cable, but imperceptible as to the angle mentioned above. Nevertheless, if you give it a little more upwards tilt than you want to end up with, that stretch will bring it down a little and you should be good.

The following youtube video gives you a rough idea of how NOT to do it. In that video, the presenter only wraps the wire twice around the shroud above and below the spreader, and shows off how well the shroud moves through the seizing at the end of the video. https://youtu.be/fb76xB8lVdk Maybe that works for that small boat, but I think we are supposed to actually SEIZE the shrouds on our larger Cape Dorys.

In order to prevent slippage, I normally add 8 to 10 tight winds above and 8 to 10 tight winds below the spreader. Also, I like to lay the seizing wire in one of the cable grooves and make my winds back over that piece of wire, which helps prevent slippage. Then connect the ends of the wire and twist it tight, snipping off the excess. Finally, encase it all in rubber spreader boots to keep the sail from chafing on it. Amazing that there are no other YouTube videos on this process, esp for big boats.

[tjr818]

Bill,
Are you sure about that? If so, I need to attend to mine soon. I took the rubber boots off this spring for several reasons, they were old and dirty, they caused the genoa to hang on the spreader tips, and I have heard that they can trap moisture which will attack the shrouds. I put genoa rollers on the shrouds above the spreaders and they ride on little washers that sit on to of the spreaders. I notice that the safety wire only wrapped around the shroud one time, not tight as you suggest. I thought the safety wire was there just to keep the shroud from slipping off of the spreader.

[Bill Goldsmith]

Pretty sure. I recall reading from Nigel Calder's Boatowner's Mechanical and Electrical Manual: The more the top and bottom shroud angles differ, the greater the bending moment on the spreader, and the more likely is is to fail (either by buckling or as a result of its tip sliding up or down the shroud. With continuous rigging [as we have, as opposed to rod rigging or other discontinuous rigging]. there needs to be some means of locking a spreader tip in place (it may have to be lashed)."

In Brion Toss's "Rigger's Apprentice" he says, in discussing many rigs where the spreaders are horizontal instead of bisecting the shroud angle: "This is the single most common flaw in rigging. If the spreader is angled properly, it functions as a pure compression member. If it is horizontal, the shroud will act to push its outward end down. This leads to an excessive buckling load on the spreader. If the end seizing slips, the spreader could collapse altogether. Dismasting. Besides, horizontal spreaders look dowdy, lifeless... To fix this, cast off the outboard seizings and tap the ends up to the proper angle. Have one of your deck crew with a good eye get well in front of the boat to help you with this. Aloft or on the ground, use a bevel gauge to get the angles identical. Finish by seizing the spreader ends securely to the wires."


AS far as the rubber boots are concerned, I don't tape them up to make them hermetically sealed. Rather, I only use enough rigging tape to hold them in place, leaving plenty of the split opening open to the air for draining and drying.

I'm sure rollers are also a great solution.

[tjr818]

Thanks Bill,
That lead to the Riggers Apprentice kept me busy for quite awhile. I pulled my copy off the shelf and dug in, he has a lot to say about spreaders. On our 27 the spreaders fit into cast aluminum sockets on the mast, so the angle is fixed. I cannot tap the spreader up or down more than a 1/4". That being said, I will do a better job of securing the end of the spreaders the next time I am near them.
Once again, Thanks for the tip ( )

[Bill Goldsmith]

No problem. I would've given you a page cite but I am working off my kindle version!!