Jack lines -- sew the loops or rivet them?

[jmschmidt]

Do both.

[davil]

Originally Posted by senormechanico

I would sew it, no question.
If you value your life, it's a pretty simple thing to figure out.

If I was making one now, I'd not use any other thread than GoreTex (Tenara).
It's guaranteed forever not to go bad in Ultraviolet.
I sewed our trampolines with it after having to restitch them every 3 years.
Last time I sewed them with GorTex. The stitching looks brand new amost ten years later.

Pricey,best price I could find was EBay, close to dollar a yard.
thanks for the info

[Aguabago]

Morgans Cloud did a very interesting study on jack lines, the forces on you when you fall (a stretchy jack line could avoid a broken rib), and the challenges on getting back on board. Their solution is pre-mounted attachment straps at hard points that they leap frog between. Its a paid site, but very worth the few bucks subscription.

https://www.morganscloud.com/2016/11...lines-forever/

[newhaul]

Tie the ends to hard points .with a couple twists to facilitate grasping with cold wet hands to clip in.
Next hope you never have to test any part of the rig regardless of how you do them.
( you fall off you die. ) my personal motto)

[thinwater]

Originally Posted by wagsea6b

+1

Tie a water knot ...

Technically, that is an overhand loop. A related knot, used to make runners, is called a water knot.

Remember that in climbing webbing, this is strong enough when used as a runner (loop), but it will be 40% under ISO strength requirements when used as a loop knot. Easy to forget, but climbers use these as loops if a hard fall is expected.

[thinwater]

I like rope. If you can locate them along a cabin side where they are not underfoot they are safe, and they can stay in the sun for years, ready for use. Fat rope also makes a nice handline. But they cannot be on the deck underfoot, so this won't work for many or most.

Perhaps the only practical DIY approach that meets all standards, is to run 3/16" Dyneema inside webbing, splicing the ends. APS sells these pre-made.

[HopCar]

Thinwater, I've used tri-bar sliders to make loops in the end of webbing many times. It is the easiest way I know to put a flat loop in webbing. I've never used it on something as crucial as a jackline nor do I have any idea how strong it is.

Have you ever tested these?

https://m.youtube.com/watch?v=Uya3uL1q3Ac

[hamburking]

Definitely sew...this distributes the load over a large area. Rivets weaken the webbing by introducing a hole, whereas a needle simply spreads the fibres apart doing almost no damage.

Sewing is much stronger.

[SVTwilight]

[QUOTE=guyrj33;2520254]

Originally Posted by billknny

I would sew loops in one side of the jack lines, and tie the other side to a cleat. You should be using nylon webbing (not polyester) for it's better UV resistance.

DANGEROUS ADVICE offered above
polyester aka Dacron has much better UV resistance than nylon.

Ultimately neither option may be optimal. Nylon is not advisable certainly and at the same time most Dacron webbing I looked at doesn’t have a high enough breaking strength esp once knots are applied. So, consider this: I bought “no stretch” spectra line and ran it through the same length of tubular Nylon webbing as an abrasion and sun cover. Easy to to tie, super strong and I can just replace the Nylon webbing periodically

And yes Dacron polyester typically has better UV resistance than nylon. In fact nylon rope generally had to be impregnated with uv inhibitors to help it last.

Certainly nylon lasts way better that polypropylene and is commonly mentioned in that regard....

[waterman46]

We attach the webbing to bow and stern mooring cleats using at least 6 figure 8s on each cleat. Wet the webbing first, pull real tight and check daily. I never noticed it getting loose but suppose depends on the type of cleat. Ours are the big fat aluminum type without a shiny finish I think this method of attachment is stronger than any of the above methods.

Always remove and store out of sun when not in use so they last years for us.

I bought white webbing but next time I will get black for nighttime visibility on our offwhite deck.

[Yeti]

During my time in the fire service we used the water knot for all our webbing based hi-angle rescue anchoring points. The webbing was usually 1" tubular webbing with a breaking strength of around 6000 lbs. Two or three anchoring points of this stuff and we would put a guy over the side of a bridge and bring him and another up.

Here's a link to the animated knots water knot page.
Water Knot | How to tie the Water Knot | Knots

[PaintedKite]

Excellent input, folks. My goodness, I'm glad I asked here at this forum. I have several options to try now, starting with tying knots. Will give it a go while still in the Bay, before going off-shore. Thx again...

[Suijin]

Originally Posted by PaintedKite

Excellent input, folks. My goodness, I'm glad I asked here at this forum. I have several options to try now, starting with tying knots. Will give it a go while still in the Bay, before going off-shore. Thx again...

Whatever you do, make sure it's easily adjustable. As noted nylon webbing can stretch considerably in varying conditions and a loose floppy jackline is a bad jackline.

Ideally, you'll have jacklines that run as close as possible to the centerline of the boat as the further from the side of the boat they are the better. Perform an analysis of your deck, factoring in tasks you perform on deck, access and interference with lines, etc. to design a workable configuration.

[David B]

Originally Posted by PaintedKite

I'm making jack lines for my 37' sloop, and I've got the heavy duty 1.5" webbing all ready to go. And I was planning on sewing the loops in each end with foot-long "W" stitches using high-strength thread.

But then I talked to an experienced commercial captain, and he said he just rivets them. He says it's much easier to do. Plus, you can rivet while you're right there on the deck, at the attachment point(s), assuring that you're getting the measurement exactly correct.

Opinions, board-mates? Which is better, sewing or riveting? Thx!

Riveting results in a small number of high-stress load points. Look at the commercial jack lines, look at the commercial bosun's chairs, the commercial climbing harnesses, the commercial car seat belts .....

Sewing (correctly) spreads the load to the point where each thread is hardly doing anything much more than just sitting there - and if one thread pops, you have many more. If a rivet head pulls through ........

Take you jack lines to the boat, measure up, make allowance for some stretch, put a few threads through to hold, then take back and sew properly - your life, or that of a crew-member, may depend upon that.

[newhaul]

Originally Posted by David B

Riveting results in a small number of high-stress load points. Look at the commercial jack lines, look at the commercial bosun's chairs, the commercial climbing harnesses, the commercial car seat belts .....

Sewing (correctly) spreads the load to the point where each thread is hardly doing anything much more than just sitting there - and if one thread pops, you have many more. If a rivet head pulls through ........

Take you jack lines to the boat, measure up, make allowance for some stretch, put a few threads through to hold, then take back and sew properly - your life, or that of a crew-member, may depend upon that.

personally I would rather my life dependant on my own tied figure8 knots and my locking caribiners.
Lost a man in '88 due to not using a jackline properly.