Best Way To Do Lightweight Stanchions/Lifelines These Days?

[Chotu]

I’m working with the fiberglass/carbon pultrusion companies right now on a big order for everything I need to buy in terms of pultrusions.

I was thinking I’d order my stanchions from them too.

My thought was to drill holes through the deck and glass (or mechanically fasten) the stanchions right to the bulkheads.

Then I’d get Dyneema and run it through the stanchions to pads at either end.

Is this a good way to go?

I was thinking hollow tubes for the stanchions. However, this could be leaky where the Dyneema passes through.

Thoughts on this?

[rslifkin]

Hollow tube stanchions should be fine, just find some way to sleeve them where the lifelines pass through. That way the lifeline holes are sealed off from the hollow interior of the stanchion.

[tkeithlu]

Tying to the bulkheads may be overkill. The edges of your deck, where it meets the hull, has a lot of structure and a lot of rigidity. Through bolting from a plate at the bottom of each stanchion, or possibly only lag bolting, should do the job.

What features of Dyneema have led to that choice rather than 7x19 SS cable?

[Chotu]

Originally Posted by rslifkin

Hollow tube stanchions should be fine, just find some way to sleeve them where the lifelines pass through. That way the lifeline holes are sealed off from the hollow interior of the stanchion.

Yes, I think I’m doubting my ability to make that sleeve watertight. I may be over thinking that.

[Chotu]

Originally Posted by tkeithlu

Tying to the bulkheads may be overkill. The edges of your deck, where it meets the hull, has a lot of structure and a lot of rigidity. Through bolting from a plate at the bottom of each stanchion, or possibly only lag bolting, should do the job.

What features of Dyneema have led to that choice rather than 7x19 SS cable?

I don’t have a hull/deck joint. It’s a radius curve and all one piece. The hull and deck are the same thing, all made in one shot with resin infusion. My hull/deck halves are joined at the keel and directly above the keel at deck level. While it’s strong there at the radius where deck turns into hull, it seems like it may need additional support to me. It’s all cored too.

I’m looking at Dyneema because it weighs a lot less than stainless and it’s “cool”. Ha ha. I’ll admit it. I think it’s cool to use cordage first lifelines.

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.

[Matt Johnson]

That's great until you break one and require a ton of surgery to replace.

Instead, glass in 1" OD G10 studs to the bulkheads, through the deck, and extend about 4" above. 1" ID carbon stanchions then just slip over the stud. It's watertight and strong, but replaceable if you do damage a stanchion.

Matt

[rslifkin]

Originally Posted by funjohnson

That's great until you break one and require a ton of surgery to replace.

Instead, glass in 1" OD G10 studs to the bulkheads, through the deck, and extend about 4" above. 1" ID carbon stanchions then just slip over the stud. It's watertight and strong, but replaceable if you do damage a stanchion.

Matt

That's probably a better way to do it.

As far as deck strength, a reasonable backing plate should provide plenty of strength even without going down to the bulkheads. Even more so if you glass the backing plate to the deck and right out to the edge and into the radius to the hull side.

[Chotu]

Originally Posted by funjohnson

That's great until you break one and require a ton of surgery to replace.

Instead, glass in 1" OD G10 studs to the bulkheads, through the deck, and extend about 4" above. 1" ID carbon stanchions then just slip over the stud. It's watertight and strong, but replaceable if you do damage a stanchion.

Matt

This is why I start these threads. Genius.

How do you usually secure the stanchions to the stubs? Set screw to a dimple in the stub?

I just googled G10. It’s is epoxy based, so I think I’ll just use a standard, solid rod frp pultrusion. Polyester.

[Singularity]

Going with a through-deck composite is a no-brainer and it should be forever water-tight unless you're doing it wrong.

Perhaps you've seen the video below; I'd suggest that they under-engineered and crudely installed things, but when you glue a solid stubby post through the deck (down and secured to the hull, or bulkhead) then there's nothing to leak. I personally would secure the topside plastic stanchion tube to the stubby with a cross-bolt or two.

This system allows repair/replacement anywhere, flexibility in having different tube heights for off-shore/condo mode if desired, etc.


On edit: missed funjohnson's post...indeed to emphasis a point above, the below-deck solid stubby needs solid attachment to something other than just the bottom/inside of the deck.


https://youtu.be/rz9S9miKm9g

[bailsout]

Remove them and don’t replace. They are a hazard.

[Chotu]

Originally Posted by bailsout

Remove them and don’t replace. They are a hazard.

What?

[bailsout]

Tether. I watched my shipmate go through one- it broke. They can give a false sense of securiy. Lines are on the outside, use handholds to the inside.

[zstine]

Tula installed Carbon stanchions. link below.. They added some thickness to the deck by bonding g10 plate above and below, then drilled ~1in holes and used a solid G10 rod maybe 10in long, bonded through the deck. The carbon slides over top the rod.

https://www.youtube.com/watch?v=rz9S9miKm9g

For your purposes, I'd consider traditional SS base plates bolted in and the carbon pulltrusion just replacing the vertical SS tube. then you don't need to do much epoxy work and SS on Carbon looks cool!


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

[rslifkin]

Originally Posted by bailsout

Tether. I watched my shipmate go through one- it broke. They can give a false sense of securiy. Lines are on the outside, use handholds to the inside.

A tether does not replace the need for good, secure stanchions and lifelines. Personally, I wouldn't be comfortable moving around a boat with no outer rails / lifelines even at the dock. They're not there to keep you from flying overboard in rough conditions, that's what tethers are for. Lifelines are to give an extra hand hold, help delineate the edge of the boat, and are useful for holding fenders when docked.

If a lifeline breaks, it was either horribly under-designed or it was long past the point where it should have been replaced. If maintained decently, that's just not a concern.

Plain and simple, the "lifelines aren't there to save you so having them is more dangerous" attitude just doesn't hold up.

[Chotu]

Originally Posted by bailsout

Tether. I watched my shipmate go through one- it broke. They can give a false sense of securiy. Lines are on the outside, use handholds to the inside.

I tend to agree with you. I’ve never found lifelines necessary, but they give a good psychological feeling to others. I’ve done 1500 nautical miles or so without them and didn’t miss them at all.

Of course I don’t tether either. There is no need to go on deck on my boat. Now, since the rig isn’t on...or later, since all sail controls are indoors.

But... I also agree with rslifkin 100%. Especially about fenders. It really stinks running a line fore and aft every time you use them.