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spectra_rudder_cable_7_3_2020

Spectra (Dyneema) for rudder cable

Reivers Dustin
Jul 3 #27054

I've assembled a couple of stern-leash running lines using Spectra and found it can be a little tricky. The issue is around fastening. It is very slippery so many normal knots don't hold well. “They” recommend that you splice everywhere you can and only use special knots if you have to. Well. That's stupid.

So I checked out how to install a spliced eye. Two hassles: you have to bury the running end 72 diameters into the working side of the line. (!). Also, you really need to taper the running end that is buried. Then to do it properly you need to do a double mobius brummel something or other. Here's a 10min vid:
https://www.youtube.com/watch?v=UpkqJ4GRfSg

woah.

But I'm still interested in designing a way to do spectra cables on my Huki (shipped with SS). So OK. Let us say, theoretically that I've properly installed spliced eye's so I can secure one end. But on the other end there is no way to install a splice. Gotta tie a knot. My normal rule on this is, “if you can't tie a knot, tie a lot.” But 'they' say you go down to 7% strength when you do crappy knots. So here's a guy who invented a couple of special knots for Spectra (another long-assed vid):
https://www.youtube.com/watch?v=b9GLp1Esins

Thats all poopy. And even then I need to get fittings of some kind that give the spectra a nice radius to grip against. So I need to shop a rigging store and find itsey bitsey clips, clamps, and fiddley bits so the line doesn't tie around sharp edges. “Tighten up that Jib Hank there, Hank!”

“If the Count of Monte-Cristo could do it, there's no reason I can't do it.” (Mike Nelson, “Sea Hunt”).
or (same actor, different movie):
“it's not a good day to quit sniffing glue”.

Nicholas Cryder
Jul 3 #27055

Drivers,

I’ve used Q power line as it’s extremely easy to knot. Haven’t one come loose after years of use. I have a large spool if you’d like to see a sample.

Cryder

Reivers Dustin

Jul 3 #27057

I'm having trouble finding tech-specs. Do you have links or something to technical resource?

Reivers Dustin
Jul 3 #27058

I found this:
https://pksdistribution.com/proddetail.asp?prod=q_powerline_pro_spool

I think this might be the line that Kai used on Vega boats. It looks good, but the claim that you can tie knots with no loss of strength is a stretch (har har). Definitely looks superior to braided spectra. Another neat thing Kai did was use cleats so clenching knots not needed necessarily (sorry, got stuck in an alliterative loop there.)

I'll still have a problem with hard edges since the stainless hardware design has different fiddley bits.

rd

James Schulz
Jul 3 #27059

http://www.powerline-sports.com/PDFfiles/PLS%20-%20Q-POWERLINE%20Data%20Sheet..pdf

John Rybczyk

Jul 3 #27060

For Pete's sake Reviers, what a lot of hassle you're going through to make a replacement cable. How old are you right now…96, 97, I'm guessing? You say that Jude's original cable lasted you for six years? How many ready-made, OEM, spare cables do you need to buy from Jude, problem solved, to last you the rest of your paddling career?

See you on the water!

SimonB

Jul 3 #27061

Whatever stuff they use on the Nelo’s is all attached with simple knots. Works great.

David Hooper
Jul 3 #27062

Reivers,
I've got a Huki cable set here in Bham; bought it a few years ago thinking I'd use it to remount my S1-R foot plate, but never did.
Paid $60, yours for $30.

Dave H.

Reivers Dustin

Jul 3 #27063

Thx DaveH, Thx Johnr. It's true. I could almost paddle without a rudder for whatever remains of my paddling career. like the Billy Joel song where the guy works himself into a heart attack so he can have a cadillac, “But at least you can polish the fender”. hehe. So I'm polishing the fender. Twinking around with the boat prolongs the fantasy. The big car top washer? That's just plain old bicep envy.

So let me milk this project for all it's worth. I'm spending my time pimping my ride. Never mind that I'm trading my VO2max for V8 and vodka.

If I muck this up, I'll be in touch on the spare rudder cables. But you guys should pull the rudder cable away from the foot peddle on your huki and take a gander in there where it rides against the foot peddle. I just bet theres some broken strands if the cable is more than four or five years old.

old man reivers.

Charlie Hamlin
Jul 3 #27065

My sailing experience with Spectra is that a well tied bowline with ,for our purpose, a two inch tail is fully reliable. Charlie

Charlie Hamlin

Jul 3 #27066

Rievers, standard SS thimbles ( LFS) provide protection on tight radii situational. Charlie

Paul Reavley

Jul 4 #27069

When I was looking at how to tie Spectra a while back I came across some recommendations for a water bowline.

Reivers Dustin
Jul 4 #27070

someone's been looking at the knotty parts of the internet.

Reivers Dustin
Jul 6 #27085

I think I can do Spectra. The problem was at the rudder yoke. No way to put thimble there. But I found 400 pound rated fishing line swivels that I can tuck in there to provide space for thimble. I'll post a photo.

I like the look of the Q-power line. I swung by the kiteboard place and they never heard of it.

I'll contact you Nicholas for a closer look and maybe a source.

rd

Reivers Dustin
Jul 9 #27099

Paddled this morning with new Q-Power Line rudder cables. Ended up with no swivels, too complicated. Just SS clip at both ends (rudder yoke and foot peddle). I found a good knot: “Double Palomar”. But I can only do this at one end (rudder end) because you have to tie both sides at perfect length or have some way to adjust.

The boat felt great. I'm still looking for a way to secure the foot peddle end. For now it's just a mess of half-hitches with electricians tape for security. This set up will not have corrosion. The Q-Power line is interesting: spectra linear core with spectra overbraid jacket. Rejects dirt, wears well, very low stretch, … I like it. It takes very sharp scissors or cutting pliers. Difficult to cut with a razor knife. Does not like flame.

I'll sort out this problem of terminating the foot peddle end. Once I'm sure, then I'll pull out my stainless cable on the other boat and rebuild with new line.

rd

Toby Cooper
Jul 9 #27100

I have been following this thread about spectra from a safe distance. I have experience working with these materials from racing sailboats, where it is used in applications previously reserved for SS wire and solid rod.

For example, it is used for backstays on ocean racers where loads exceed 20,000 lbs., and is often tied on with half hitches, not bowlines which would ball up and never get undone. You just have to avoid bending it over sharp edges of any kind. The loads on a ski rudder assembly are miniscule, for even the smallest diameter spectra.

RD is right. It is a superior setup, assuming you can solve the adjustability problems. Otherwise you are forever fiddling with knots. I have wanted to do this on my Fenns and would like to check out some of your solutions next time I am on your side of the pond.

Toby

Paul Reavley
Jul 9 #27101

Reivers,

What's the diameter of the Q-Power line you chose? Would adding line tensioners help with the knot at the pedal end question?

Reivers Dustin
Jul 9 #27102

great idea. I'm studying on it. It's a tight fit for my legs in the cockpit, so I'm worried these will interfere. I have to sit in the boat and check the room. thx Paul.

Reivers Dustin
Jul 9 #27103

Looking at these:
https://giantpygmy.net/shop/index.php?id_product=48&controller=product

I says good down to 3/64“ line. My 1/16” stuff equates to 4/64“ so that checks. Still, plastic cleat against spectra might not grip. Might have to buy & try. Also, there's a swedish version like the austrailian one you've linked to. The Swedish one is slightly smaller, but not as positive looking.

The saga continues.

Paul Reavley
Jul 9 #27104

My Think surfski uses one single bigger one like the australian ones in front of the feet to adjust tightness for both pedals together. Denise's Nelo 550 uses a different kind of tensioner with a camming stopper, one on each cable, but I haven't come across an online description of that version of tensioner.

Spectra (Dyneema) for rudder cable
Larry Bussinger

Jul 9 #27105

I wouldn't use one of these. They will only work if its holding tension. If the line relaxes, nothing jams and the adjustment is lost. Like a tent peg, you pull the peg and the line can slide..

Reivers Dustin
Jul 10 #27106

decided. screw it. gonna bless it with a smudge stick and call it good.

rudder stuff
Reivers Dustin

Aug 6 #27337

I changed out S1-R rudder cable from stainless to spectra. But because the rudder yoke has sharp edges I installed a rudder clip that gave the spectra a smooth piece to anchor against. I'm attaching two photos (hope it works).

rudder0.jpgrudder1.jpg


Re: rudder stuff
Dennis Mowry

Aug 8 #27354

You can't see it on the pic of my K1 but I have stainless rollers the cables run through at the rudder. Less resistance and stress.
I'll send you a pic when I get back from the Gorge. It would be nice if you bringing your boat down to test it out.
:D'

spectra_rudder_cable_7_3_2020.txt · Last modified: 2020/09/21 02:26 by preavley