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Old 14-08-2023, 16:03   #226
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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Originally Posted by The Yacht Rigger View Post
RE using halyards forward. I MUCH prefer to take a separate dedicated piece of low stretch line - dyneema - and physically tie it around the mast above the headstay, and use that to "static" tie to a strong point forward - IE your bow beam. We use truckers hitches.

It's definitely happened in the past to other riggers - the halyards can roll on the masthead sheaves and allow the mast to fall backwards. Actually happened to a rigger I know while he was up the rig - he almost died. Then you back up the static line with halyards. You retrieve it later once the mast is secure.



Or, have the crane wait while you measure rake and form the sta-lok fitting and connect the headstay. Just don't leave the rig supported on halyards only.

When you write ďrolling on the sheaveĒ, you mean that the halyard was released at the base of the mast and that allowed it to run out?

If so, that is incompetence in action and not an intrinsic fault of using halyards to support the mast. After all, sails donít randomly lower because their halyards inadvertently release?
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Old 14-08-2023, 16:21   #227
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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And if I have no running rigging (winches) yet?

I have only cleats.

Winches are in a box. Getting the rig up so I can then do the running rigging

I think the only way it can slide on the sheaves is if the rope has stretch.

While not having winches is not ideal, you can still stand the mast up by crane and support it sufficiently with halyards tensioned by hand and/or come-along/block and tackle. As Jedi says, the tension to hold a mast vertical is in the order of tens of pounds - easily within human non-assisted power.

Once the mast is standing roughly in position you need to establish and set the rake. Start with too little rake, so all you are doing is easing the bow halyards (you do have cleats on the mast?). Add a block and tackle or come-along to each shroud and use those to pull the mast back until you have the rake you need. Lock the bow halyards and tension the shrouds so that the mast is steady - that will require several hundreds of pounds of tension. Now you can measure and fit your forestay.

Once your forestay is secure, move your bow halyards to either chainplate and as best as you can replace the tension in the shrouds with tension in the halyards. Now you can work on your shroud extensions.

The amount of stretch in a non-Dyneema halyard is minuscule at the low amounts of tension that weíre talking about. And youíre not going to be the idiot that releases a halyard that is supporting the mast, are you? I acknowledge that Yacht Rigger is talking from his professional experience, but releasing a supporting halyard is carelessness, and that can be guarded against.

When weíve done this, we tape over the winch, clutch, or cleat that is securing the halyard that is supporting the mast. It takes deliberate actions to remove the tape, then release the halyard. Itís a little like locking off and securing an electrical circuit at a remote panel before working on a downstream component.
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Old 14-08-2023, 19:58   #228
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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When you write ďrolling on the sheaveĒ, you mean that the halyard was released at the base of the mast and that allowed it to run out?
No, that is not what he means. The halyard remains fixed / cleated the entire time and yet it is possible for the tip of the mast to move.

The problem is that instead of the distance (length) of the forestay being fixed, it is now the total distance from the stem (halyard attachment forward) up to the top of the mast and down to the cleated halyard (or turning block at base of mast) that becomes the fixed length. There are conditions where the mast tip can therefore move along the fixed line (the sheave making it easier by reducing friction). It may help to consider the construction of drawing an ellipse with sting and a couple nails. Or maybe picture a unicycle on a tightrope - the length of the rope is fixed but the shape of the triangle changes as the cycle moves along it.

Some factors that might increase the chance of this occurring are: stretch in the halyard, low initial tension in halyard, rake, lateral movement of mast tip, bending of the mast, and movement of mast base.

I expect that most of the time the mast tip is stable and the conditions are rare, but as The Yacht Rigger's buddy found out, not impossible.
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Old 15-08-2023, 06:15   #229
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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No, that is not what he means. The halyard remains fixed / cleated the entire time and yet it is possible for the tip of the mast to move.

The problem is that instead of the distance (length) of the forestay being fixed, it is now the total distance from the stem (halyard attachment forward) up to the top of the mast and down to the cleated halyard (or turning block at base of mast) that becomes the fixed length. There are conditions where the mast tip can therefore move along the fixed line (the sheave making it easier by reducing friction). It may help to consider the construction of drawing an ellipse with sting and a couple nails. Or maybe picture a unicycle on a tightrope - the length of the rope is fixed but the shape of the triangle changes as the cycle moves along it.

Some factors that might increase the chance of this occurring are: stretch in the halyard, low initial tension in halyard, rake, lateral movement of mast tip, bending of the mast, and movement of mast base.

I expect that most of the time the mast tip is stable and the conditions are rare, but as The Yacht Rigger's buddy found out, not impossible.

Exactly. Thanks for taking the time to explain it.
People always think that we have an nefarious motive of some sort when it comes to this kind of thing and bringing up this issue. I literally gave a simple, zero cost, extremely effective solution to the problem.
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Old 15-08-2023, 06:22   #230
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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Not sure what stories those riggers told you, but the mast can not roll on the masthead sheave and fall backwards. It is impossible by laws of nature. The only way this can happen is if the halyard is released at the mast winch.

With the main halyard as backstay and the genoa halyard as forestay, both on the mast winches, you can set the rake perfectly and nothing rolls over sheaves.
All it takes is a LITTLE bit of stretch, and then it goes past the point of no return. In one case the added rake from a little stretch actually broke/sheared the mast step so the mast foot jumped forward, allowing the rig to collapse. I don't know why people always think us riggers are making things up, when we actually stand to benefit financially from masts falling down. All we are doing is explaining what has actually happened out in the field, because this is what we do.
In another case, a guy left his rig secured by halyards and went away for lunch... came back to the rig down, halyards still secured - a little creep/stretch was all it took.
Again, no need for me to make this stuff up. It happens, and I prefer people to be aware of the risks, as opposed to just causally telling them to "secure" the mast with halyards while they stand underneath it.
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Old 15-08-2023, 06:36   #231
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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People always think that we have an nefarious motive of some sort when it comes to this kind of thing and bringing up this issue. I literally gave a simple, zero cost, extremely effective solution to the problem.
I can see where this would get very frustrating.

I think the problem in the industry is there are a few really bad apples.

Also, the marine industry in general is filled with a lot of rotten apples. So people are always on the defensive about it. I know I am. I just lost $25,000 and there’s almost nothing I can do to get it back except a long protracted legal battle. And I’m not going to waste my time on that. ( I’m sure the guy is glad to be reading this. )

It’s people like that in the industry that are fairly prevalent, though not as outrageous in their level of theft, that make it hard for a good, honest shop I think.

I am now officially a customer of you guys. I can say it’s the best experience I have had on any marine project with any outside person so far. I mean, we will see when I go to fit it in about a week. Ha ha. But I bet you it’s going to be right.

But I think reputation builds itself. If you let that feeling that everybody thinks you are trying to rip them off roll off your back and just keep doing what you’re doing, you’ll come out on top. Not that you guys aren’t already. You already have a good reputation. But what I mean is people will start to become less defensive because they know your reputation.
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Old 15-08-2023, 06:46   #232
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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I can see where this would get very frustrating.

I think the problem in the industry is there are a few really bad apples.

Also, the marine industry in general is filled with a lot of rotten apples. So people are always on the defensive about it. I know I am. I just lost $25,000 and thereís almost nothing I can do to get it back except a long protracted legal battle. And Iím not going to waste my time on that. ( Iím sure the guy is glad to be reading this. )

Itís people like that in the industry that are fairly prevalent, though not as outrageous in their level of theft, that make it hard for a good, honest shop I think.

I am now officially a customer of you guys. I can say itís the best experience I have had on any marine project with any outside person so far. I mean, we will see when I go to fit it in about a week. Ha ha. But I bet you itís going to be right.

But I think reputation builds itself. If you let that feeling that everybody thinks you are trying to rip them off roll off your back and just keep doing what youíre doing, youíll come out on top. Not that you guys arenít already. You already have a good reputation. But what I mean is people will start to become less defensive because they know your reputation.
Haha! Man, if that Martingale doesn't fit I will be shocked. But... can't say we get things right 100% of the time. What I can say is we MAKE them right 100% of the time.
It is what it is, and I hear you. The lack of standards and training in this industry is rife - we do hear horror stories fairly frequently. We also see the flip side a lot - because we allow owner involvement on major projects at our facility. People often think our labor time estimates are ridiculous, until they get involved alongside us and see just how damn difficult it is doing most big boat projects. We have a 600 hour project going on right now on a big cat, and the owner is here every day - and he's definitely seeing just how long it takes to do something right - not begrudgingly - he gets it - but its definitely still eye opening.
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Old 15-08-2023, 08:07   #233
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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Originally Posted by The Yacht Rigger View Post
All it takes is a LITTLE bit of stretch, and then it goes past the point of no return. In one case the added rake from a little stretch actually broke/sheared the mast step so the mast foot jumped forward, allowing the rig to collapse. I don't know why people always think us riggers are making things up, when we actually stand to benefit financially from masts falling down. All we are doing is explaining what has actually happened out in the field, because this is what we do.
In another case, a guy left his rig secured by halyards and went away for lunch... came back to the rig down, halyards still secured - a little creep/stretch was all it took.
Again, no need for me to make this stuff up. It happens, and I prefer people to be aware of the risks, as opposed to just causally telling them to "secure" the mast with halyards while they stand underneath it.
Well, what can I sayÖ this is a very different story than the one I commented on. Iím just an engineer, not a rigger, but you first wrote that the mast came down because the halyard sheaves rolled over the halyard. You didnít mention the maststep shearing and the mast foot jumping forward. If that happens with a forestay then the mast also comes down.

The only difference is the amount of stretch that doubles. If that couple inches movement of the masthead is enough to break the mast step, then the mast step is the problem as dynamic forces on the mast step during sailing are much higher than during raking an unloaded mast.

No, Chotu does not need to get the calculations for forestay length right. He can use a halyard and mark the forestay for cutting in place. Itís great when a rigger can do this from a shop by using knowledge and calculations only known to riggers, but copying a stay or measuring in place also works and is perfectly safe if mast steps donít break.
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Old 15-08-2023, 08:18   #234
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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Well, what can I sayÖ this is a very different story than the one I commented on. Iím just an engineer, not a rigger, but you first wrote that the mast came down because the halyard sheaves rolled over the halyard. You didnít mention the maststep shearing and the mast foot jumping forward. If that happens with a forestay then the mast also comes down.

The only difference is the amount of stretch that doubles. If that couple inches movement of the masthead is enough to break the mast step, then the mast step is the problem as dynamic forces on the mast step during sailing are much higher than during raking an unloaded mast.

No, Chotu does not need to get the calculations for forestay length right. He can use a halyard and mark the forestay for cutting in place. Itís great when a rigger can do this from a shop by using knowledge and calculations only known to riggers, but copying a stay or measuring in place also works and is perfectly safe if mast steps donít break.
The broken step was one case. The other case I know of first hand, the mast was able rake too far back and came down with the halyard still intact (So yes, the halyards rolled on the sheaves, and the step was not broken. I've heard second hand of this happening a few other times. (Yes the bottom back edge of the mast got a little crumpled but was not the cause).
In the case where the step broke.... the stretch allowed the mast to start leaning, the added load aft resulted in more stretch, until the mast was raked back far enough to break the step. The step is designed for some lateral load, but really it's mostly vertical compression that the step is there for. So it was certainly not a design flaw in the step itself, but rather a result of it being incorrectly loaded. It was a production boat, hundreds and hundreds of them are out there sailing around without step failures.
Of course there was an insurance investigation after the incident, and the step was inspected for flaws (would have been very convenient for the rigger if some were found). None were. The mast simply leaned too far back due to a combination of halyard stretch and sheave movement and overloaded it.

I don't know any riggers that will calculate forestay length using trig. Everyone steps the mast, secures it, measures rake, and then makes the headstay. Even on brand new production boats, on the initial commission, we do the same thing. I'm talking major mast manufacturers here. The big three for sure.
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Old 15-08-2023, 08:45   #235
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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I don't know any riggers that will calculate forestay length using trig. Everyone steps the mast, secures it, measures rake, and then makes the headstay. Even on brand new production boats, on the initial commission, we do the same thing. I'm talking major mast manufacturers here. The big three for sure.
I feel like this is really the only way to do it.

Not because the trig could ever be wrong, in fact, it’s more accurate than your eyeball would even be trying to mark a measurement.

However, the initial measurements you make in order to arrive at the length can be highly suspect given deck slope, the deckhouse being in the way, etc.

I see errors of inches involved.

It’s always just easier to not measure things when building whenever possible.
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Old 15-08-2023, 08:51   #236
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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I feel like this is really the only way to do it.

Not because the trig could ever be wrong, in fact, itís more accurate than your eyeball would even be trying to mark a measurement.

However, the initial measurements you make in order to arrive at the length can be highly suspect given deck slope, the deckhouse being in the way, etc.

I see errors of inches involved.

Itís always just easier to not measure things when building whenever possible.
That's exactly it. Also it's about economy. The required measuring, lofting etc of the boat, takes WAY longer than just stepping the rig and doing the measurements once it's up.
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Old 15-08-2023, 12:00   #237
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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The broken step was one case. The other case I know of first hand, the mast was able rake too far back and came down with the halyard still intact (So yes, the halyards rolled on the sheaves, and the step was not broken. I've heard second hand of this happening a few other times. (Yes the bottom back edge of the mast got a little crumpled but was not the cause).
In the case where the step broke.... the stretch allowed the mast to start leaning, the added load aft resulted in more stretch, until the mast was raked back far enough to break the step. The step is designed for some lateral load, but really it's mostly vertical compression that the step is there for. So it was certainly not a design flaw in the step itself, but rather a result of it being incorrectly loaded. It was a production boat, hundreds and hundreds of them are out there sailing around without step failures.
Of course there was an insurance investigation after the incident, and the step was inspected for flaws (would have been very convenient for the rigger if some were found). None were. The mast simply leaned too far back due to a combination of halyard stretch and sheave movement and overloaded it.

I don't know any riggers that will calculate forestay length using trig. Everyone steps the mast, secures it, measures rake, and then makes the headstay. Even on brand new production boats, on the initial commission, we do the same thing. I'm talking major mast manufacturers here. The big three for sure.
This is physically not possible. You can let go of the halyard and the mast will come down just like when you let go of the forestay, but with the halyard secured and not broken, it is impossible that the mast comes down backwards.

Itís physics.
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Old 15-08-2023, 12:07   #238
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Exclamation Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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This is physically not possible. You can let go of the halyard and the mast will come down just like when you let go of the forestay, but with the halyard secured and not broken, it is impossible that the mast comes down backwards.

It’s physics.
Speaking of physics, it definitely depends on the tension and how stretchy the halyard is.

I did think of a way around the problem however. Some insurance.

Just tie a large stopper knot in the halyard or tie a steel rod into it so it can’t go anywhere once past a certain point.

Tie this on the feed side (not the temporary halyard side) and you could eliminate any chance of this happening.

On masts with in mast halyard routing, it would stop before entering the mast. With outside halyards, a bit more difficult because it would happen aloft.
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Old 15-08-2023, 12:25   #239
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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This is physically not possible. You can let go of the halyard and the mast will come down just like when you let go of the forestay, but with the halyard secured and not broken, it is impossible that the mast comes down backwards.

Itís physics.
Spoken like a true engineer... No malice intended, I promise.

Sometimes real world events and engineering theory argue with each other. I promise it can occur. One day maybe I'll rig up a mini example on our boat show mast and demonstrate/test it. All it takes is a little stretch.

Bottom line. A static line is a simple fix that removes any doubt.
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Old 15-08-2023, 15:06   #240
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Re: Chotuís Advanced Standing Rigging Thread (lots of pics)

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Spoken like a true engineer... No malice intended, I promise.

Sometimes real world events and engineering theory argue with each other. I promise it can occur. One day maybe I'll rig up a mini example on our boat show mast and demonstrate/test it. All it takes is a little stretch.

Bottom line. A static line is a simple fix that removes any doubt.
Example: I = 60í and J = 20í. Those are reasonable numbers for many yachts, rounded for easy math.

The forestay is therefor 72í (Pythagoras)

When the mast is down, the distance between these two points is 60 + 20 = 80í.

So that ďlittle stretchĒ is 8í of stretch. So yes, when you use paracord instead of a Dyneema halyard then I can believe it. The halyard is 60 + 72 = 132í so 8í stretch is 6% stretch.

The thing is that Dyneema stretches less than 1% at 30% breaking load. Even under half the weight of the mast, which only happens halfway coming down, you are far below 0.5% stretch.

So those stories, if true and letís assume it really happened, were not with actual halyards but with a piece of string that was used as a halyard.

Now if the mast step breaks and the foot of the mast jumps forward, then yes, this wil happen but in that case it will also happen with a steel forestay attached.

Then a detail that bothers me enough to address it: you wrote ďyou only need to go a little too far with setting rake for it to triggerĒ. But when you set rake, you have a plump bob hanging down from the masthead so you can measure the distance between the back of the mast and the plump bob, so that you know the rake. While you do that, the halyard is already stretching. You tension the main halyard in itís backstay role (why would you use a halyard there but not as forestay?!) then slowly give a little genoa halyard to increase rake.

There is one more possibility: the genoa halyard wasnít tightened, or someone was feeding it to get more rake while noone was pulling on the backstay, with the mast just balancing, then suddenly falling backwards as there is lots of slack in the genoa halyard.

You will never know because they will never admit to the mistakes they made, but nowyou can show them that their stories require 8í stretch
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