7x19 Wire Shrouds

[SuperPiper]

She's only a little boat and she gets trailered a bit more than some.

I changed the shrouds from 1x19 to 7x19 halyard wire a 1/2-dozen seasons ago. The 1x19 would get kinked while stepping the mast or while trailering or from other abuse associated with having the mast laying across the cabintop.

I did step up from 1/8" to 5/32". So far, I'm very pleased with the outcome. The soft & pliable wire can be bundled out of the way easily without fear of kinking or causing a lantern.

I've helped to step masts on bigger boats with rod rigging. That can be like petting a porcupine.

So, what are the disadvantages of 7x19?

[michael pierzga]

Fish hooks , longevity, stretch, strength. But it sounds like a good choice for a small trailer sailor. Next rigging change investigate fabric rigging.

http://www.colligomarine.com/

[Dean Smith]

made me smile I saw a superyacht the other day, the lowers were 63mm at a guess solid rod. the boom was at least 4 feet deep, mind simply boggles
here she is launching, possibly the ugliest darned supeyacht money can buy Alongside her at the old cement wharf in Auckland is another perhaps longer superyacht, a replica looks like, she is all grace. Talk of chalk and cheese

[DGreenwood]

An, as yet, relatively undiscovered boon to the small boat sailors of the world, is the magic of synthetic fiber rigging. MP is right, it is hard to find a reason not to use it for small trailer launched boats. Light, flexible and strong. Keep it covered from UV when not in use and it will last a long time.

[Dean Smith]

An, as yet, relatively undiscovered boon to the small boat sailors of the world, is the magic of synthetic fiber rigging. MP is right, it is hard to find a reason not to use it for small trailer launched boats. Light, flexible and strong. Keep it covered from UV when not in use and it will last a long time.
you are right, the strength of Spectra for standing rigging and kevlar for halyards is unbelievable
We use spectra on the furl lines . You could just throw it is your car boot
7x19 was used a lot for halyards , galve did not spragg as much as ss(fish hook) Now it is all kevlar

[SuperPiper]

You are probably right. Synthetic fibre rigging is the way of the future. Fortunately, my stainless steel 7x19s will last another 20 years and the synthetics technology will have matured by then. I would think that UV resistance should be in the design brief for sailboat rigging (or a written disclaimer about "not suitable for outdoor sailing").

[DCockey]

Our trailerable sailboat has 7x7 rigging which is much more flexible and less prone to kinking than 1x19 but has less stretch than 7x19. It's not as widely available in stainless as 1x19 or 7x19.

[philSweet]

One "note" regards synthetic rigging. I've heard a couple reports of boats being refitted with synthetics that hummed outrageously. Owners couldn't stand being on the boat. The only thing I can think of is that the spirals on wire rigging trip the vortexes in a random manner and that limits sympathetic vibrations.

[CutOnce]

One "note" regards synthetic rigging. I've heard a couple reports of boats being refitted with synthetics that hummed outrageously. Owners couldn't stand being on the boat. The only thing I can think of is that the spirals on wire rigging trip the vortexes in a random manner and that limits sympathetic vibrations.

I've been using synthetic rigging on a dinghy for years - I'm happy. I do reduce rig tension to the point where it is no longer "singing" when the boat is on the dolly - basically the boat doesn't need the stress when unnecessary. I crank up the rig tension based on conditions and setup.

I've got the rig tension set by 8:1 control on the forestay, which routes to both sides and can be adjusted under way.

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CutOnce

[SuperPiper]

I've got the rig tension set by 8:1 control on the forestay, which routes to both sides and can be adjusted under way.




This has been percolating in my noggin'. I'm starting to really warm to the concept. My boat's forestay needs to be replaced. It is still 1x19. Where did you get the synthetic forestay? DIY? Made to length? What fittings do you have at the ends?

What are the details for the 8:1? Is there a hard connection in addition to the 8:1 tackle? I'd hate to see the mast come down because someone's butt cheek accidentally released a cleated downhaul. Do you have a photo?

[CutOnce]

This has been percolating in my noggin'. I'm starting to really warm to the concept. My boat's forestay needs to be replaced. It is still 1x19. Where did you get the synthetic forestay? DIY? Made to length? What fittings do you have at the ends?

What are the details for the 8:1? Is there a hard connection in addition to the 8:1 tackle? I'd hate to see the mast come down because someone's butt cheek accidentally released a cleated downhaul. Do you have a photo?

Just bought at The Chandlery here in Ottawa, cut to length. Used SS thimbles at the ends. There is a becket block on the bottom of the forestay, and a turning block at the deck fitting (2:1). Then it routes to a 4:1 that goes across the foredeck, which is split to go to both sides. Each trimming line is knotted outside the clam cleat, preventing a mishap with accidental uncleating. I'll try to dig through photos to find one.

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CutOnce

[SuperPiper]

Doesn't the becket block give you 3:1 for a total of 12:1?

The SS thimbles are in eyes in the synthetic stay? Who made the splices? The Chandlery?

Yeah, a photo please. This sounds great!

[SuperPiper]

CO have you got a photo of this setup?

[CutOnce]

CO have you got a photo of this setup?

I've got to drop the boat down from the garage roof this week - I'll take a picture.

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CutOnce

[Stumble]

Just to be clear, rope rigging is a great advance, and can save a lot of weight on money compared to wire or even rod rigging. I love the stuff, and plan on switching to it on the race boat, but there are some significant differences and issues.

1) Kevlar, and most synthetic line is not acceptable replacements. Currently the only line that is sutable for replacing standing rigging is called Dynex Duc.

2) Unlike wire it is not sized based upon MBL but instead on stretch resistance.

3) UV concerns while valid are proving not to be a real concern. Expected current replacement life for the Dux is about 5 years, vs 6 for rod, and 8 for wire. But since the end fitting are easily reusable the first replacement is measured in hundreds of dollars (For an Olson 30) instead of thousands for rod.

4) Professionaly splicing is recommened to remove constructional stretch before instalation, but is not required. I know people who replaced their entire standing rigging by themselves.

5) Did I mention that currently only Dynex Duc is a reasonable replacement?

[AsterixDeGaul]

Our trailerable sailboat has 7x7 rigging which is much more flexible and less prone to kinking than 1x19 but has less stretch than 7x19. It's not as widely available in stainless as 1x19 or 7x19.

hehehe... Last time I saw 7 x 7, it was used as clothes line ;)

7 x 19 will stretch far too much for any standing rigging but i suppose if you never go out in over 12 knts, you will never notice :P

[DCockey]

For the same diameter:
7x7 stretches 76% more than 1x19
7x19 stretches 138% more than 1x19

Sounds like a big difference, but how big is it in absolute terms?

Whether that is "too much" depends on the rig and how critical a small performance increment is.

With our boat it's not a noticeable difference, but then we don't race and a performance oriented sailor wouldn't sail our boat.

http://www.loosco.com/index.php?page=wire-rope-stretch

[DCockey]

One "note" regards synthetic rigging. I've heard a couple reports of boats being refitted with synthetics that hummed outrageously. Owners couldn't stand being on the boat. The only thing I can think of is that the spirals on wire rigging trip the vortexes in a random manner and that limits sympathetic vibrations.

Probably a combination of larger diameter and lower mass of the synthetic rigging compared to wire rope or rod. Frequency of shed vortices is inversely proportional to the diameter. Modal frequencies are inversely proportional to the square root of the mass. So if the tension is the same, a larger diameter, lower mass synthetic stay will shed voritices at a lower frequency and have higher modal frequencies. More likely that the frequencies will match and the stay will hum.

[Stumble]

DCockey,

One of the problems with 'stretch' in wire rigging is that often what you see is elongation of the wire as the wire starts to unwrap. This constructional stretch (CS) is fine, but one of the problems with using wire with more CS is that it takes significantly more pre-tension on the rigging to get the same mast bend. This extra load must be carried all the time, and of course adds to the total loads the rig experiences when shock loading. This can lead to faster failing of hardware, oil canning, detaching the deck ect..

Of course this isn't always so extreme, but in one case we measured a reduction of the static load on the top stays of 40% when switching from wire to dynes duc. I highly highly doubt this is typical, but reductions of 10-15% seem normal. The worst case was a very tall mast with lots of rake, and very small wire. This lead to really cranking on the tension to get the right shape in the mast.

[SuperPiper]

For the same diameter:
7x7 stretches 76% more than 1x19
7x19 stretches 138% more than 1x19



I really appreciate a sailor who can quote the numbers. You are good.

Unfortunately, your numbers are not in my favour. You make my 7x19 substitution look questionable.

I did increase from 1/8" 1x19 to 5/32" 7x19 so I may not be too disadvantaged. Also, I'm not sure that a little bit of stretch in the shrouds will be discernible with a mast just the diameter of your wrist. The rig would probably be soft even with SS rod rigging.

Good info. Thanks DCockey.