Pad Eyes for Life Lines - Load Rating

[squarehead67]

My understanding is there is no specific load rating for pad eyes intended to be used to attach a harness to - is this correct? My internet searches are not providing any topics that cover just how secure these pad eyes should be. Does anyone have any insight on this?

[billknny]

There is an extensive treatment of this topic in Brion Toss' book "The Rigger's Apprentice."

It's complicated, that's why you won't find a simple answer to it on the internet.

[roverhi]

I've used cast SS or bronze 4 bolt triangular based padeyes for Jack Line attachment. https://hardware.schaefermarine.com/...frt0r6snujm0m3

[GordMay]

Greetings and welcome aboard the CF, squarehead.

Yes, there are working load limits for lifting pad eyes; however they may not apply to your application (angular load angles).
➥ https://www.lift-it.com/info-forged-eye-bolt-warning
➥ https://www.jwwinco.com/uploads/tx_r...load_rings.pdf
➥ https://www.witpress.com/Secure/ejou...MEM060314f.pdf

[Breaking Waves]

Originally Posted by squarehead67

My understanding is there is no specific load rating for pad eyes intended to be used to attach a harness to - is this correct?

Your question is a bit confused - do you mean for "lifeline" (as in the title) or for "Harness" (eg Jackline) as in the post body? Those are two different applications, with different rules.

But the simple answer (actually in either case) is breaking strength (on load axis) to exceed 2040kgs (4500lbs). There are complexities, but that will mostly do it.

[SV Tru]

World Sailing 2018-2019 Offshore Special Regs:

3.14.6 e) All components of lifeline enclosure system shall have breaking strength no less than the lifeline.
4.04 Jackstays and Clipping Points
4.04.1b) have a breaking strength of 2040kg (4500#) and be ......
4.04.1c) enable two-thirds of the crew to be simultaneously clipped on without depending on jack stays

Above are extracts only. Use in conjunction with rest of relevant Sections.

[SVTatia]

The SWL on the example provided by Roverhi is 4K pounds. I think this is sufficient for the dynamic load of stopping a body attached to it..assuming the jackline matches the strength.

[thinwater]

The offshore rule does NOT say SWL, it says BS. This is a common misunderstanding. Climbing gear in general is based in breaking strength, not SWL. The difference is included in the reasoning.

The rule was based on experience with polyester lines jacklines, on boats up to 50 feet, with one person on the jackline. If the boat is larger, if you use Dyneema, or if you foress a bunch of people on the line, te strnegth will need to be higher. https://www.practical-sailor.com/iss...n_11853-1.html

[acem]

Be sure to have a substantial backing plate or it could be pulled out.

My catalina 27 pulled two cleats off with backing plates when the marina was hit by a tornado. The other two held. One line snapped while the other broke out part of the marina. I kept that piece as a souvenir.

Thx-Ace

[zstine]

I would just size the pad eye to exceed the strength of the wire or rope it holds. This is a general rule for all applications as I personally don't want the mounting point failing before the stuff it is holding.

[squarehead67]

HI- I'm looking at the padeye attached on the boat (with 4 screws - in most cases) - that is sometimes pointed out as a location to attach your harness - 4 screws? I cant find any documentation as to design requirements for a padeye with this intended use.

[zstine]

I don't see an attachment, but it should be through-bolted, not screwed into fiberglass. The holes in the hardware dictate the diameter of the bolts.

[Benz]

Originally Posted by squarehead67

HI- I'm looking at the padeye attached on the boat (with 4 screws - in most cases) - that is sometimes pointed out as a location to attach your harness - 4 screws? I cant find any documentation as to design requirements for a padeye with this intended use.

It would be difficult to create documentation for a boat, given the almost infinite amount of variables, and the fact that 'design requirements' aren't made by any governing agency (unlike cars, for example), but are very individual to designer/builder/owner. So you have to become an engineer of sorts and consider questions like: how long are the screws? what are they made of? what is their age? followed by even more important questions about what they go into and what is behind it. You can't just slap a padeye willy-nilly onto any surface, stick a backing plate behind it and expect the best. The surface may not be able to take the loads. One small boat I had would oil-can in various places when stepped on; I had to add or replace core in several spots. So to have a huge Harken padeye with backing plate attacked to a 1/8" thick glass mat cabin side defeats the purpose.
In summary: use common sense and good judgment to engineer your safety equipment; no amount of published material could account for every boat in every situation.

[Breaking Waves]

Originally Posted by squarehead67

HI- I'm looking at the padeye attached on the boat (with 4 screws - in most cases) - that is sometimes pointed out as a location to attach your harness - 4 screws? I cant find any documentation as to design requirements for a padeye with this intended use.

breaking strength (on load axis) to exceed 2040kgs (4500lbs) is the closest you will find.

no rule I am aware of specifically calls out required strength for individual padeyes to which you directly clip a tether/harness. But the above 2040 kg is a widely used racing requirement for various components in this sort of use (like jacklines and their attachment points).

Tethers have for a while been required to have “overload flags”, which are supposed to pop at (variously from different mfg’s) in the 500-900lb range, and no-one that I have every talked to (and I know most of the folks involved in this application) has ever seen one of those flags “popped” while sailing (only in various artificial test circumstances). So, the 4500lb requirement probably has a significant safety margin built in, but that is also probably appropriate for this application.

Two notes on padeyes - you probably want them thru bolted (to decent backing plates) rather than “screwed”, and it is useful to put strong Dyneema loop on the padeyes and clip to the loop rather than to the padeye, because this will minimize the possibility of side loads being put on your clip (which can bend or open even the best tether clips).

On many work station padeyes it is convenient to have a strop w/clip permanently spliced to the padeye. You clip this to your harness. This strop can be the exact shortest length allowing you to work at that workstation. Thus #1 that strop is always there, so you always have something to clip in with even if you forget your tether (and even if you also forget your harness, you could clip to your belt - better than nothing) and #2 it is the best/safest length, unlike your more general purpose tether.

[thinwater]

Originally Posted by squarehead67

HI- I'm looking at the padeye attached on the boat (with 4 screws - in most cases) - that is sometimes pointed out as a location to attach your harness - 4 screws? I cant find any documentation as to design requirements for a padeye with this intended use.

Same spec.

Read the World Sailing Off Shore Rule. It's in there.


Also remember that direct clipping to a fixed point generates incredible impact forces. Clip your tether to something rigid, gather 6 feet of slack, and take a run at it. It will hurt you, perhaps badly.



And pick your clips carefully.

https://www.youtube.com/watch?v=CbyhyC7ua8g