Best Way To Do Lightweight Stanchions/Lifelines These Days?

[tkeithlu]

If you go with hollow tubes (we use thin wall SS 1" tubing) and can't make them waterproof where the lines come through, drill a drainhole at the bottom. But, Bailsout has a good point about not installing jib-ripping devices up your foredeck. Just be aware that ABYC says you need them.

[Matt Johnson]

Originally Posted by zstine

Stanchions are not typically lined up with bulkheads. I think there may be a quasi standard distance between stanchions..?

Distance between stanchions is 2.2m / 87" or less per ISAF (which I believe is the same as ISO/RCD requirements). There is probably a bulkhead or frame to tie into within that span on all boats.

Matt

[guyrj33]

One advantage to metal stanchions is they bend and by doing so absorb some of the force.

[bcboomer]

On a boat that big railings would be nice.

Whatever you do make sure the lifelines are high enough to do more than just flip you over them.

[Chotu]

Originally Posted by funjohnson

Distance between stanchions is 2.2m / 87" or less per ISAF (which I believe is the same as ISO/RCD requirements). There is probably a bulkhead or frame to tie into within that span on all boats.

Matt

This is accurate for my boat. There is no span greater than 8 ft without a bulkhead. And that’s just by memory.

[Sailing Ohm]

If they are not built to actually withstand the load of a falling person then they can be misleading and probably are more dangerous than not having them. BUT Lifelines are a a nice safety feature. They are the last resort and should ideally be used in conjunction with a Jackline/tether system.

A few years ago I replaced my entire lifeline/stanchion system. Here’s what a remember:
Practical sailor tests found that the weakest link is not the stanchion, wire/dyneema but the pulpit/pushpits which collapsed at a fraction of the rope/wire (if the pulpit rail was vertical vs angled and if attached to those weak little welded on eyes then forget about it)
Be careful with hollow stanchions was also the advice I saw. (Remember that’s what failed first in the pulpits/pushpits). Some super thin walled tubes are not rated high enough for ISAF safety regs and easily bend under the loss imparted during a fall.
Solid aluminum stanchions were rated as some of the highest. Carbon fiber is still not recommended.

A lot of the problems, outside of wire corrosion, were due to improper backing and weak stanchion bases. I know I’ve personally seen quite a few ripped from the deck (on old and new boats). Especially since that outside edge is a tough place to put backing plates, etc.

I think with the usual safety factor each part of the system needs to withstand 3,800lbs of force. A 200 person falling from the high side of a deck imparts about 950lbs of force and a 4:1 safety factor is usually used.

When it comes to safety I think focusing on trying to get something ‘lightweight’ is a mistake. It’s meant to keep you in the boat so I think sacrificing a few pounds for safety is Prudent. (There’s loads of other places you can save weight instead of crucial safety equipment). When you actually need to use them I’m thinking you’d want the most rock solid hardware you could have.

Needless to say I think a lot of boats out there, even some high price tag newer yachts, have improperly designed and rated lifeline and stanchions.

I ended up going with 3/8 dyneema lifelines and solid aluminum stanchions with bases that also clip under the toe rail. Each lifeline is lashed around the pulpit railing not clipped. Each base has a custom made G10 backing plate permanently bonded to the hull/deck joinery. It was a very difficult job due to access to the underside but our stanchions are rock solid.

We have two small dogs on board so we actually ended up putting netting between our lifelines and I have to say I’m loving it. It has caught a few pieces of gear (winch handles to name an important one) from going overboard. Not to mention it makes it impossible to slide between the top and bottom lifeline.

[zstine]

keep in mind the stanchions and lifelines work as a system. Typically, there is a curve to the boat, bow to stern, and the tension in the lifelines pull the stanchions inboard and help distribute outward directed loads (ie falling person). It is not expected that one stanchion alone would stop a falling person.

[Dsanduril]

Originally Posted by zstine

keep in mind the stanchions and lifelines work as a system. Typically, there is a curve to the boat, bow to stern, and the tension in the lifelines pull the stanchions inboard and help distribute outward directed loads (ie falling person). It is not expected that one stanchion alone would stop a falling person.

This is something that gets missed a lot. What you say is true of a monohull, but is generally not true on multihulls (cat or tri). Our hulls (as an example) are 50' long and the total depth of the curve over that length is less than 1'. Compare that with a monohull of that length where the chord toward the bow (at least) would be 5-7'. Multihulls take a bit more thought as there is no "arch" in the lifeline structure as is found on monohulls. This means that loads are concentrated more at each stanchion than they are on a monohull.

[s/v Jedi]

No G10 because it’s epoxy based? For glassing in epoxy is needed as well. Also, carbon fiber is epoxy based, right?

G10 rod and sheet is many times stronger than frp counterparts. Also, it is much stiffer and that is what you need in this application.

I think you will need to hire someone for this job. I do not think stainless steel plates and hardware is a good replacement: it is a recipe for leaks and corrosion because it’s not open to the air.

[rslifkin]

The concern with G10 is just around dust from cutting / drilling, correct? If so, would it be possible to either get pre-cut pieces, or mark it out and have someone else cut and clean the parts?

[Nauticatarcher]

Stanchion-carbon Fiber 650mm - Stanchion-carbon Fiber - BlueShark Marine Co., Ltd.

[fxykty]

Originally Posted by Chotu

...Side question: how long does Dyneema last in the sun? Chafe will be a non issue since it’s just sitting there anyway. No loads. Maybe fender loads occasionally.

UV damage is a minor issue, as long you don’t use minimum size line.[LIST][*]5mm is the minimum according to ISAF, 6mm is a safer bet. Strength will be much higher than the equivalent 7x19 SS wire so you have some wiggle room.[*]Uncovered is fine, though cover helps prevent chafe damage. No cover allows easier inspection. [*]8-10 years should be achievable, similar as for Dyneema rigging.

Chafe is the issue. [*]Don’t tie your fender lines to the lifelines, tie them to the stanchion bases.[*]Be very careful with sheets and other lines that cross the lifelines, especially if they move.[*]If you can’t guarantee that the holes through the stanchions start out and remain absolutely smooth, then add short chafe sleeves at each stanchion.[*]Don’t clip halyards to the lifelines.

We’re swapping our tired SS lifeline wires for 6mm uncovered Dyneema, with short chafe sleeves at each stanchion. We’re eliminating all metal components except for the pad eyes at either end. In particular, metal pelican hooks at gates are very weak. Less weight and more strength. We’re going to need to be very careful with our screecher and spinnaker sheets - perhaps chafe cover on the upper lifeline over that area?

[Dsanduril]

Originally Posted by fxykty

...
We’re swapping our tired SS lifeline wires for 6mm uncovered Dyneema, with short chafe sleeves at each stanchion. We’re eliminating all metal components except for the pad eyes at either end. In particular, metal pelican hooks at gates are very weak. Less weight and more strength. We’re going to need to be very careful with our screecher and spinnaker sheets - perhaps chafe cover on the upper lifeline over that area?

We replaced our wire with 6mm Dyneema two-three years ago and have been quite happy. Pretty much exactly as you describe, the only metal in the whole system is the attachment points at the ends, chafe sleeves at each stanchion (those are still metal but slated to go carbon hence my interest in this thread). We haven't had any issue with sheet chafe, our sheets occasionally touch the lifelines but they don't ride on them for any length.

[Chotu]

Originally Posted by s/v Jedi

No G10 because it’s epoxy based? For glassing in epoxy is needed as well. Also, carbon fiber is epoxy based, right?

G10 rod and sheet is many times stronger than frp counterparts. Also, it is much stiffer and that is what you need in this application.

I think you will need to hire someone for this job. I do not think stainless steel plates and hardware is a good replacement: it is a recipe for leaks and corrosion because it’s not open to the air.

It’s the machining. When you machine cured epoxy it frees up some of the amines from the polymer. I would never have known this if I didn’t have this happen and cause me to have an anaphylactic reaction. So, I’m getting all remaining parts in polyester to keep the epoxy work to a bare minimum.

I can certainly size a polyester round tube to be as strong or stronger than a given epoxy tube bu changing the wall thickness.

So I’m sticking with that. We’ll see about bedding them. Still working on a complete solution.

[SailSonoma]

I've had dynema life lines on my boat for several years now; really love them. They were easy to install, once you do two or three splices and locking stitches, you can do it with your eyes closed. They look great and are easy to replace/maintain