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Old 07-10-2015, 22:02   #1
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Could you install double sets of stays and shrouds?

Just out of curiosity...would it be safe and possible to install a second set of shrouds and stays side by side with the existing primary rigging?

point being to make a super strong mast that would survive a failure of any one of the pieces of the standing rigging. so lets say a upper shroud or backstay fails, the other shroud or backstay rigged right by its side would absorb the load and the mast would suffer no failure or damage.

obviously this would require welding and installing new attachment points to the mast and installing new chainplates etc....assuming these components were installed in a location that was directly side by side of the original attachment points...do you think it would be safe and effective?

probably a silly question from a novice but was reading about rigging failures tonight and was thinking...if one was considering a solo passage across a major ocean...the extra security might be nice to have unless there are already simpler alternatives.

iv'e never heard of any boat actually rigged like this though so i'm guessing maybe its unsafe or very impractical?

thanks...just curious and trying to learn....
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Old 08-10-2015, 00:29   #2
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Re: Could you install double sets of stays and shrouds?

I think Jon Saunders did this on Parry Endeavour when he did his incredible 3x non stop around the world voyage. But it would add significant weight, windage and cost. And in a often it's fittings like the spreaders or chainplates that fail, so you would need to back them up as well. Better maybe to use overstrength dynex dux

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Old 08-10-2015, 01:18   #3
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Re: Could you install double sets of stays and shrouds?

There are a number of issues that can come up.

The primary is weight up high is bad for stability. Suprisingly small amounts of weight can have major impacts.

Also, there are situations where you want things to give. Better the rig fall down than rip the entire transome off.

Rigs very rarely fall down and most times, it's user error not design fault.
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Old 08-10-2015, 03:56   #4
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Re: Could you install double sets of stays and shrouds?

Greetings and welcome aboard the CF, er.
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Old 08-10-2015, 09:41   #5
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Re: Could you install double sets of stays and shrouds?

Unless it's catastrophic, you can go on the opposite tack and rig a halyard to ease the strain. Don't overburden your rig with too much pressure and they seldom fail.
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Old 08-10-2015, 09:57   #6
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Re: Could you install double sets of stays and shrouds?

Short answer, yes it would be possible and could be done in way that's safe. The bigger question is would it make sense or contribute to the safety of the rig. I think the answer there is no. Way better to make the existing mast and rigging bulletproof than to try to double up.

You can go with titanium chainplates and bolts. Top of the line, oversized wire, etc for a much more practical, usable rig.
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Old 08-10-2015, 10:06   #7
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Re: Could you install double sets of stays and shrouds?

Some voyagers have installed a second headstay for "double headstay." I see nothing wrong with that.

The OP mentions they have been reading about dismastings.

Rather than doubling all the shrouds and stays, one could eliminate them altogether!

Learn more by reading the following thread about Sailboats with Freestanding Masts.

Sailboats with Free Standing Masts
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Old 08-10-2015, 12:40   #8
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Re: Could you install double sets of stays and shrouds?

Quote:
Originally Posted by er9 View Post
Just out of curiosity...would it be safe and possible to install a second set of shrouds and stays side by side with the existing primary rigging?

point being to make a super strong mast that would survive a failure of any one of the pieces of the standing rigging. so lets say a upper shroud or backstay fails, the other shroud or backstay rigged right by its side would absorb the load and the mast would suffer no failure or damage.

obviously this would require welding and installing new attachment points to the mast and installing new chainplates etc....assuming these components were installed in a location that was directly side by side of the original attachment points...do you think it would be safe and effective?

probably a silly question from a novice but was reading about rigging failures tonight and was thinking...if one was considering a solo passage across a major ocean...the extra security might be nice to have unless there are already simpler alternatives.

iv'e never heard of any boat actually rigged like this though so i'm guessing maybe its unsafe or very impractical?

thanks...just curious and trying to learn....
I'm sure you could do that. Some yachts have been fitted with 2 fore stays and 2 back stays. I don't think you could get equal tension in each pair, so one wire would take most of the load. If it broke I'm guessing the shock load could possibly make its companion give way as in a progressive failure. It would need more holes in the mast which would weaken the mast. The spreaders would need to be bigger and heavier to attach 2 wires to. The weight and windage of the rigging would double. The boat might need some more ballast to counter the extra weight aloft. Better to spend the considerable extra cost on replacing the rigging maybe every 10 years. The most common cause of rigging wire breaking is from corrosion. Spreader failure for whatever reason can cause the rig to fail. Rigging wire is extremely strong and doubtless you could lift a boat using one wire.
What else would you double? Amateur boat builders sometimes make the hull out of maybe 50% thicker timber. Then the hull will be 50% heavier. Carry 4 anchors instead of 2 etc etc. you eventually end up with a dog that won't sail.
Good designers do all the calculations and there is usually no need to double up on any aspect.
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Old 08-10-2015, 18:05   #9
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Re: Could you install double sets of stays and shrouds?

kinda like the question, 'if airplane black boxes are indestructable why not make the whole airplane out of the same materials?' of course first they're orange not black, second, no number of jet engines could lift the weight, third...........ah hell, never mind.
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Old 08-10-2015, 19:24   #10
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Re: Could you install double sets of stays and shrouds?

some interesting insight and info...thanks for the replies.
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Old 10-10-2015, 20:36   #11
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Re: Could you install double sets of stays and shrouds?

Quote:
Originally Posted by er9 View Post
Just out of curiosity...would it be safe and possible to install a second set of shrouds and stays side by side with the existing primary rigging?

point being to make a super strong mast that would survive a failure of any one of the pieces of the standing rigging. so lets say a upper shroud or backstay fails, the other shroud or backstay rigged right by its side would absorb the load and the mast would suffer no failure or damage.

obviously this would require welding and installing new attachment points to the mast and installing new chainplates etc....assuming these components were installed in a location that was directly side by side of the original attachment points...do you think it would be safe and effective?

probably a silly question from a novice but was reading about rigging failures tonight and was thinking...if one was considering a solo passage across a major ocean...the extra security might be nice to have unless there are already simpler alternatives.

iv'e never heard of any boat actually rigged like this though so i'm guessing maybe its unsafe or very impractical?

thanks...just curious and trying to learn....
a lot of extra weight and windage
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Old 10-10-2015, 23:11   #12
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Re: Could you install double sets of stays and shrouds?

I suspect most of the rigging losses are on boats with minimalist rigging. If you have inner and outer forestays, double backstays, upper, intermediate and for and aft lower shrouds and keep them in reasonable condition there is only a slight chance of losing your rig.

Although it tends to have less corrosion problems stainless steel is not the best material to rig a sail boat with as it tends to work hardening and subsequent failure. But it looks good. Galvanized rigging is not subject to this problem but does not look as "yachty" and will rust if the zinc galvanization wear off.
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Old 11-10-2015, 00:19   #13
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Re: Could you install double sets of stays and shrouds?

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Originally Posted by Steady Hand View Post
Some voyagers have installed a second headstay for "double headstay." I see nothing wrong with that.

The OP mentions they have been reading about dismastings.

Rather than doubling all the shrouds and stays, one could eliminate them altogether!

Learn more by reading the following thread about Sailboats with Freestanding Masts.

Sailboats with Free Standing Masts
I know of one extremely experienced sailor with multiple circumnavigations who rigged his new yacht with 2 free standing masts. I saw it under construction and from inside the finished hull he showed me the strong mast partners which reinforce the "mast holes" in the deck; the masts going down to the keel. Unfortunately he got it wrong and in a fierce squall one of his masts broke below the deck and thrashed around making a hole and sinking the yacht in very deep water. Fortunately nobody was injured.
Things can go wrong with any design and there is always a weak spot somewhere. Best to stay home and not go outside if you are too worried.

I saw a cartoon showing a person suffering from agoraphobia and chlaustraphobia symiltaniously. He continually kept running out to the gate and back inside again. Sh.. happens sometimes even if what most people do safely is mostly safe. As one of my late colleagues kept saying. Life is not a dress rehearsal.
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Old 11-10-2015, 00:26   #14
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Re: Could you install double sets of stays and shrouds?

We have a double forestay setup that gives us good redundancy. Particularly nice when you consider that the self furling foresail foil can hide all sorts of problems if you are not careful.

We have a fair bit of duplication elsewhere in the rig, but I was still slightly envious of the Parry Endeavour when we visited it in Freemantle. My favourite part of that rig was the triple (or maybe just double?) rear stays which I personally feel are a good idea. At least I think they would be good on our boat.


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Old 11-10-2015, 02:56   #15
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Re: Could you install double sets of stays and shrouds?

What you're inquiring about has actually been done, many times, on a whole bunch of different boat designs. Usually by folks new to sailing, & who wan't "bulletproof" rigs. It's not as tough as many here make it sound, & 150yrs ago, it was kind of common practice.

Also I've seen a few commercial designs where what you're proposing was done, or real close to it. And because of the extra windage, when a breeze as stiff as all of 25kts would kick up, he'd heel over 10-15 degrees in his slip.
In case you're curious, it was a Hans Christian design.

The weak points of any rig, generally speaking, are the end points of the wire; where it enters into the terminal fittings, & the various end fittings connecting things together. Such is the case even with Rod.
That's where say, 98%+ of all failures occur.

One rig design which will intrigue you, as it's kind of along the lines of what you're thinking, is the B&R rig (Bergstrom & Ridder). There's not exactly an encyclopedia of info about them out there, but the design's both unique, & has a lot going for it.
- Enough so that Hunter, de-tuned it a bit, & put it on several lines of their boats.

In theory, it has; more performance for less weight aloft, & redundancy in rigging wires... plus a bit more tuneability in one's rig.
Look up the vessels; Route 66, Tuesday's Child (or maybe Thursday's), the Hunter HC 50, & you'll also run across the name Warren Luhrs in conjunction with many of these. Also, there's info on such in the Dashew's book, below.

Do yourself a favor, & pick up copies of:
Brion Toss's The Rigger's Apprentice
The Dashew's Cruising Encyclopedia vol. II <-- Get a used copy on Amazon/Ebay/Half.com for 1/2 price.
If you study them well, you'll know more about rigs, rigging, & structures than 99% of the sailors afloat. Including bits on rig design, safety factors, pro's & con's of rig types, & various materials, weight aloft, failure modes inspecting things... et all.
Not to mention sailing in general, & cruising.

They're a bit out of date when it comes to say, synthetic rigging, soft shackles, & the like. But such info is easy to pick up online. Have a look over at www.forums.sailinganarchy.com & www.L-36.com there's LOTS of practical knowledge at the latter. And doing some perusing @ www.bethandevans.com wouldn't hurt either, given their depth of knowledge, & all of the sailing that they've done.

Also, Evans has done a LOT of work with some of the top riggers, & line manufacturers, to come up with KISS methods for using the modern high tech lines for all kinds of mundane uses, formerly reserved for pricey metal fittings & such alone.


PS: When it comes to doubling up on shrouds, it's not Too uncommon, to see 2 cap shrouds per side, & double lowers (fore & aft leading). As these are the 2 places, generally speaking, which get the highest side loadings on the rig. And which the rig will, without question, fail, if they do.
Look at boats designed for expeditioning, especially at the extreme ends of the spectrum, latitude wise.
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