Tendons: is anyone else seeing more failures lately?

[gvictor]

I have broken three tendons Neil Pryde tendons over the past four months. Yesterday I lost a brand new race rig (Maui Sails TR16 7. when the tendon and safety lines both broke during a jibe. The swell broke my mast and the mast ripped the sail, and so I took my boom off and let the ocean claim the rest.

After discussing with others on beach, they are reporting more tendon failures, too. My buddy uses Chinook, though.

Has anyone else noticed lower durability of tendon universals?

Thanks,

Victor

Sailing spot: Kailua, Oahu

[joethewindsufa]

man, that is TOO nice a sail to lose over a tendon + safety cords %^&*()

time to switch to a mechanical one ??

[dllee]

I guess tendons first became popular in the mid '90's, Streamlined.
For several year's, they seemed bullet proof, but still experimental. Then they went thru a bad batch in the early 2000's, were dozens broke in each sailing area, and lots of folk went back to rubber uni's, while some stuck out the bad batch era and they got good again.
Mid 2000's, several different companies started making tendon style joints, and of course, quality control with new items started showing up again.
10 year's later, a mix of OEM parts, good and bad, Monday/Friday or mid week made, it's inconsistent, just like the rubber uni joint.
Mechanicals are more solid, but so is the connection while you're sailing.

[pmlct]

No problems with my Chinooks. Two of them are about 4 years old, still ok but will be replaced in the spring as a preventative measure. One broke last winter after about 4 years but was an older design Chinook so I think it sat on a store shelf for awhile before purchase, accounting for the aging and breaking-but it got me back to shore. No experience with NP tendons. Sorry to hear of your troubles.

[GURGLETROUSERS]

Been using the new North two piece tendon u.j. since it came out just over a year ago. It reverts to the 'old' way of a seperate base plate, and a slotted in (prong sliding inro groove) tendon part with solid stainless top with North pin (one piece as Chinook) and stainless bottom part.

The innovative feature is that the transparent tendon has a straight thin Dyneema rope running through its centre, with loops corresponding with the top and bottom holes in the tendon for the stainless pins slotted through. The non stretch rope prevents the tendon from stretching at all and relieves it from tearing stresses. In effect it works like a mechanical joint, free to bend, but not to stretch. (And probably tranfers the stresses to the boards mast track.)

The inatial batch had some tendon failures (mine split at the base hole in the first couple of weeks) but North replaced them all with a claimed uprated tendon, which so far, after just over a years use, has shown no sign of failing. (When the original tore the rope held it together and I didn't even know there was a problem before I seperated the rig and noticed the pin was leaning over from vertical, so the rope obviously worked.)

I can't verify how it would stand up to big surf (such is beyond me nowadays) but it has been used for moderate surf, and in very high winds, and for bump and jump, and longboard use without trouble. I can't see how it would be less strong than the normal rubber U.J.'s. (It certainly costs a lot more !!)

[kevinkan]

I have not seen abnormal rates of failure for Streamlined tendons. It is important to inspect your tendon occasionally. I attach my uni to the board and then attach a bare extension and bend it to the sides. You can see pretty far up the tendon caps (at least w/ Streamlined unis) and see if the tendon is tearing at the screw hole.

It's also important to have good quality rope that's in good condition with good knots as a safety line. I see a lot of sailors out there w/ torn safety lines/straps on various unis.

[Darbonne]

I had two tendons break this year, however both were on used Kona bases. One of them broke the first time I used it. Going to replace with Chinook. You get what you pay for.

[manuel]

Wow, so sad! Sucks big time.

I have noticed some premature cracking with my streamlined tendons where the bolts slide in, (70 sessions?) until I realized that I had a gap between the tendon and the housing. It's important that the tendon is almost pressed in when installing it.

So I installed a washer to fill the gap and the cracks took much longer to develop (maybe 200 sessions now?). Still after a crack start showing up it takes a while to reach failure (I never did and always replaced before).

Your case seems extreme. The streamlined tendons are built like tree trunks that's why they take a while to tear even after the first cracks appears.

Where is it cracking? Can you post pictures of the base and tendons?

[brynkaufman2]

I had a new one break on me within a couple months. As Joe suggested I switched to the mechanical and feel a lot more confident now.

https://chinooksailing.com/index.php/windsurf/bases/euro-pin/2-bolt-quick-release-mechanical-mast-base-euro-pin-ex.html

It is hard for me to tell the difference. In really light winds I feel I get a little bit better performance to start planing early from the mechanical, but in normal winds I can't tell the difference.

[wsurfn1426]

I saw someone come in with a broken tendon this weekend in Corpus. He stated it "was not that old", but I don't know any details of its true age. It was a Chinook.

I currently replace all my tendons yearly along with my outhaul, boom clamp inhaul, and mast base downhaul. It is no guarantee, but it really sucks when something breaks at the wrong time (surf, cold weather), and it is cheap and easy to do. So far I have been very lucky. I hope there is not a manufacturing problem that exists.