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Old 27-03-2017, 08:33   #76
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Re: Don't push on stanchions! Here's why...

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but a dockhand bending a stanchion by pushing on it a few times doesn't speak well for the integrity of the system.
A dockhand trying to stop a 40 ft Valiant by the stanchion for 31 years might cause it to flex a little and disturb the bond, don't you think ?
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Old 27-03-2017, 09:10   #77
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Re: Don't push on stanchions! Here's why...

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Originally Posted by rhubstuff View Post
We're heeled over 25-30 degrees in 20 knots of wind, and you're going to say "Let's get the crew on the weather rail, but don't touch the lifelines." Say what?
LOL ! Perfect !
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Old 27-03-2017, 09:34   #78
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Re: Don't push on stanchions! Here's why...

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Originally Posted by rhubstuff View Post
I can exert a horizontal push of maybe 80-100 pounds. If I were to fall against the lifelines during a knockdown, I might exert 250+ pounds of force against them.
Depending on how heavy you are, and the nature and the force with which you hit your lifelines obviously being the biggest factors, your lifelines could be subjected to sudden forces of thousands of lbs.

Assumption: Personal weighing 200lbs and falling 4 ft.

E = (200 lbf) (4 ft)
= 800 ft lb

Assumption, direct impact to stanchion (1/4 inch of give on the stanchion):
F = (800 ft lb) / (0.0625 ft)

= 12800 lbf

Assumption, hit lifelines, 3 inches of give once lines begin to resist impact:
F = (800 ft lb) / (0.25 ft)

= 3200 lbf
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Old 27-03-2017, 09:40   #79
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Re: Don't push on stanchions! Here's why...

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Originally Posted by Calif.Ted View Post
A dockhand trying to stop a 40 ft Valiant by the stanchion for 31 years might cause it to flex a little and disturb the bond, don't you think ?
Do you still have the same sails, sheets, stays and halyards after 31 years too?
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Old 27-03-2017, 09:48   #80
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Re: Don't push on stanchions! Here's why...

Just deciding what kind of boat to buy...leaning toward a trawler but sailboats ard still in the running. This thread just about knocked sailboats out of the running.

Say what...do not touch that...it might break??? Yikes, aren't those lifeline made of cable???
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Old 27-03-2017, 10:01   #81
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Re: Don't push on stanchions! Here's why...

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Originally Posted by tuffr2 View Post
Just deciding what kind of boat to buy...leaning toward a trawler but sailboats ard still in the running. This thread just about knocked sailboats out of the running.

Say what...do not touch that...it might break??? Yikes, aren't those lifeline made of cable???

Well, if you want a boat the very first step is to take everything you read on cf with a good dose of salt.

The op was making the point that using gear contrary to its intended purpose results in doing extra maintenance. Fair enough. There is nothing fragile about a sail boat. How many 28 to 40 ft trawlers have circumnavigated? Obviously fuel is the issue but strength of purose, sailboats are just fine!
Every boat, be it trawler or sailboat, requires knowing that your actions have consequences on the equipment. Know what they are and choose your actions wisely. Pretty simple really.
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Old 27-03-2017, 10:32   #82
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Re: Don't push on stanchions! Here's why...

Route out the core, glue and glass in fiberglass tube for the s/s staunchion.
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Old 27-03-2017, 10:50   #83
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Re: Don't push on stanchions! Here's why...

Even funnier than an anchoring thread, because so many of the responses, from smart people, make even less sense.

FTR, I have had boats with and without. All of the designs made good sense; those without did not need them, and those with were well designed and served a valuable purpose.
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Old 27-03-2017, 11:02   #84
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Re: Don't push on stanchions! Here's why...

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Originally Posted by tuffr2 View Post
Just deciding what kind of boat to buy...leaning toward a trawler but sailboats ard still in the running. This thread just about knocked sailboats out of the running.

Say what...do not touch that...it might break??? Yikes, aren't those lifeline made of cable???
Don't let this thread dissuade you. Stanchions just plain shouldn't be weak, that's all. Lots of people are afraid of scratching their toys, when really you should just be handy and know how to fix stuff that breaks or get scuffed or scratched...that will be NO DIFFERENT for a power boat. Powerboats have their own set of problems that sailboats don't have, such as high usage hours on their engines, more frequent overhauls and re-powers.

Power boats and sailboats doesn't really have a cost savings vs each other...a sailboat generally has a lower powered engine which reduces costs, but it has sails and rigging which increase costs...a sailboat of _an age_ has 1/25th the number of hours engine running than a powerboat of the _same age_ (I am generalizing here) and burns a lot more fuel.

The operating and maintenance costs for either boat are roughly the same, it's not how many dollars, its what each dollar gets spent on.

Some people say for a boat that is going to circumnavigate, the cost of a set of sails for a sailboat is going to be the same as the cost of the fuel to do the same in a troller.

So....decide what you want to do, do you want to sail or do you want to motor...then pick you boat....one advantage of a sailboat is you can still motor if you want to.
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Old 27-03-2017, 11:34   #85
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Re: Don't push on stanchions! Here's why...

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Originally Posted by mkriley View Post
The big question is why do people accept the overpriced crap like the OP's stanchion bases. The old cast wilcox bronze bases were strong enough to not do that bending.
Build the things strong enough in the first place, weak decks are a separate issue.
mk
In all other respects they are well made and sturdy. The holes that the lifeline wire passes through have a ferrule welded in. They have beefy backing plates and are made of good quality stainless.

I think they bent over 31 years of service. I was actually wondering if they were intentionally designed this way as they are similarly bent, to a degree, but there's no reason for it and the gate stanchions, which are doubled up, are not that way.. They are all strong enough to keep you from going over, and are of the taller variety.

I'm of the mind that lifelines are for steadying yourself as you move forward and i've certainly used them on in rough weather for this purpose...not relying on them as my primary handhold but as a secondary when necessary. They were also certainly help prevent me from sliding off the deck as well.

A couple of years ago I was racing on a friends First 36.7, which has the lower lifelines that are popular these days I did "test" the stanchions on a spinnaker run when working bow and moving the 150 over for the rounding. In a rather freakish "perfect storm" of events I ended up suspended upside down by the knees from the lifelines with my feet trapped under the sail.

The stanchion where I fell backwards was bent out at 45 degrees. If it had not bent, I might well not have been able to get my feet out and ultimately get myself back on the boat. Who knows.
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Old 27-03-2017, 13:05   #86
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Re: Don't push on stanchions! Here's why...

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Originally Posted by Suijin View Post
In all other respects they are well made and sturdy. The holes that the lifeline wire passes through have a ferrule welded in. They have beefy backing plates and are made of good quality stainless.

I think they bent over 31 years of service. I was actually wondering if they were intentionally designed this way as they are similarly bent, to a degree, but there's no reason for it and the gate stanchions, which are doubled up, are not that way.. They are all strong enough to keep you from going over, and are of the taller variety.

I'm of the mind that lifelines are for steadying yourself as you move forward and i've certainly used them on in rough weather for this purpose...not relying on them as my primary handhold but as a secondary when necessary. They were also certainly help prevent me from sliding off the deck as well.

A couple of years ago I was racing on a friends First 36.7, which has the lower lifelines that are popular these days I did "test" the stanchions on a spinnaker run when working bow and moving the 150 over for the rounding. In a rather freakish "perfect storm" of events I ended up suspended upside down by the knees from the lifelines with my feet trapped under the sail.

The stanchion where I fell backwards was bent out at 45 degrees. If it had not bent, I might well not have been able to get my feet out and ultimately get myself back on the boat. Who knows.
I have seen the exact stanchions you have snap off at the welds to the base in more than one case. The welds also can corrode, very poor design. You need to adjust your thinking as you have turned a defect in the stanchions into a feature
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Old 27-03-2017, 13:36   #87
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Re: Don't push on stanchions! Here's why...

Quote:
Originally Posted by Scot McPherson View Post
Depending on how heavy you are, and the nature and the force with which you hit your lifelines obviously being the biggest factors, your lifelines could be subjected to sudden forces of thousands of lbs.

Assumption: Personal weighing 200lbs and falling 4 ft.

E = (200 lbf) (4 ft)
= 800 ft lb

Assumption, direct impact to stanchion (1/4 inch of give on the stanchion):
F = (800 ft lb) / (0.0625 ft)

= 12800 lbf

Assumption, hit lifelines, 3 inches of give once lines begin to resist impact:
F = (800 ft lb) / (0.25 ft)

= 3200 lbf
Nice, actual math. Yes, the force will likely be more than 250 pounds.

a. An 8-knot stumble (13 ft/s) = 200 x 13^2/64 = 528 ft-pounds. Add a little down wards fall (2ft x 200) = 400 ft-pounds) and the 800 ft-pounds might even be a little light, demanding on the size of the boat. But clearly the correct order of magnitude.

b. The stretch will be a lot more than 3 inches, since the stanchions will bend. The force will not be steady, but gradually increasing in a difficult matter to predict. Let's assume the stanchions bend 6 inches and the actual absorption range is more like 9 inches. Assuming the The force increases linearly, the peak force will be about 2 x 800/(0.75)= 2133 pounds. Since the BS is 4500 pounds, we are past the WLL of the cable (900 pounds), but this is normal for foal protection equipment, and within the range generally accepted by military and climbing standards (generally around 1200 pounds for harness impacts).

So in a worse-case fall, rails will bend, but the sailor will be retained.

And for those who believe they are a hazard, no one said you need to stand tall when it gets wild--get low. You can't fall over a rail if you are crouched, kneeling, or crawling. This is obvious. Your first reflex when you loose your balance should always be to get low.


As for using the lines, I'm a big believer in pulling up. It will not loosen them and can give a lot of stability.
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Old 27-03-2017, 15:07   #88
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Re: Don't push on stanchions! Here's why...

I'd be scared about the rest of the boat if the stanchions couldn't stand a sailor pulling on them.
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Old 27-03-2017, 15:46   #89
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Re: Don't push on stanchions! Here's why...

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Originally Posted by Scot McPherson View Post
Do you still have the same sails, sheets, stays and halyards after 31 years too?
I've worn out those items and replaced them but I've never worn out a stanchion.
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Old 27-03-2017, 15:47   #90
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Re: Don't push on stanchions! Here's why...

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Originally Posted by mkriley View Post
I have seen the exact stanchions you have snap off at the welds to the base in more than one case. The welds also can corrode, very poor design. You need to adjust your thinking as you have turned a defect in the stanchions into a feature
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How have I turned a defect into a feature?
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