Best Mainsail Halyard Material

[GinoDelG]

Hello,

I'm planning on replacing the main halyard on my Brewer 44 cutter. It's got a roller furling boom. What do people think would be the best material and size for the job. Currently it's got 1/2" double braid polyester. I'm looking for something with less stretch, but not crazy expensive.

I'm hoping that if I can go down to 7/16" the sail might be a bit easier to raise. But how can I tell if my winch and clutch can handle the smaller diameter?

Gino

[Brion Toss]

Hello,
Ah, a good halyard challenge. You want something that is inelastic enough to give that good design a chance to sail up to its potential, yet not "crazy expensive." I don't understand why coming down a size would make the sail easier to raise; care to elaborate? In any event, the most halyard for the money would be a blended core, like New England's VPC. It stretches, about half as much as double-braid Dacron of the same diameter, and is only about 30% or so more expensive, depending on where you get it. If 7/16" is right for your boat, no harm done. But if it isn't, then stay with half. Have you run any numbers on halyard loads?
Another option would be (mostly) uncovered Spectra, spliced to a fat Dacron tail. This would minimize stretch and weight aloft, and wouldn't be a whole lot more expensive, even including the joining splice.
Get back to us about those halyard loads.
Fair leads,
Brion Toss

[GinoDelG]

Hi Brion,

The New England VPC was my first choice too.

As for loads, my boat is a 29,000 pound 44-foot cutter. Using the Lewmar formula in the back of your book (which is terrific by the way), I calculate the loads to be 1,500 pounds, if I'm doing this right.

I assumed the resistance when raising my main halyard would be reduced by switching to a smaller diameter halyard because there would be less surface area and therefore less drag over the sheave and through the fairleads.

BTW, I like your suggestion to use Tig instead of cotter pins on my stays. I'm not near my boat at the moment. Would it be safe to assume that I would need the 3/32 diameter vs the 1/6?

Gino

[MichaelKa]

Hi All,

I have a pair of oversized latex gloves that I want to custom fit to my hands. Does anyone here know what the best material or method would be to accomplish that?

[allene]

You might enjoy this calculator LINK I set it up for your boat with a P of 46 and 1500 pound load. It shows the stretch for various line materials. StaSet 1/2 inch is 9 inches so that is your starting point if you really get that load. If you used 5/16 Amsteel and covered half of it with the cover you strip off your existing halyard you have a very inexpensive solution with a bit less than half the stretch. For some reason I am not showing VPC to be less stretch that SatSet which is kind of odd but that is what the numbers show given the published strength and stretch. The datasheet on StaSet says the stretch is 1% at 10% of load and the datasheet on VPC says it is 1.3% stretch at 10% of rated strength. Doesn't seem right but that is what they publish.

I got the dimensions HERE so your actual setup might be less with a mast mounted winch or a fair amount more with a halyard led back to the cockpit.

[Brion Toss]

Hi,
He's usually a very, very reliable source, but those figures on Sta-Set vs VPC are wrong. Sta-Set is rated at1.6% stretch at 10% load, and VPC at .7% at 10% load. Yup, less than half the stretch. The 2 ropes are approximately the same strength. The handiest place to check this is on West Marine's site.
Fair leads,
Brion Toss

[allene]

I thought the numbers strange so I checked the data sheets.

http://www.neropes.com/Datasheets/IND_STASET.pdf
http://www.newenglandropes.com/Datasheets/MAR_VPC.pdf

It is easy to correct my table if I could find a source for the numbers for 10%, 20%, and 30% stretch for each line.

I saw the WM numbers but I don't always trust them either which is why I went to the NE Rope data sheets.

[allene]

I have emailed nerope asking them to give me good data. It seems clear that the data below, from their datasheets, is not correct.

It could be a matter of different test methods as I know specifying rope stretch is more complicated than it would appear to be at first.

[GinoDelG]

I just found an article from Practical Sailor (Nov. 2010) rating various lines. In the mid-range category they rate VPC the best and state that it has half the stretch of Sta-Set, although I'm not sure whether they actually tested the numbers or not.

[GinoDelG]

I take that back, reading the sidebar they did test stretch and found it to be half that of Sta-set.