Saturday, June 13, 2009

Chinook Tendon Maintanance

On my recent OBX trip, I spent one morning at Sailworld with my friend Andy McKinney. It hadn't started blowing yet, so we decided to give my extensions a close examination.

Now mind you, I think I take reasonably good care of my stuff. But I had never taken apart my extensions to examine the tendons.

I use the Chinook euro-pin tendon design. I have three of them, and they are all in their 3rd year. Overall the piece is bullet proof. Unfortunately you cant see the part that fails until its too late (2 Miles off shore in an offshore wind). the only part that tends to fail on you is the tendon itself. But the part of the tendon that fails is concealed just below the stainless steel.

Click on these pictures to get the full screen view

The hole you see thru the tendon is where the crew passes thru to attach to the stainless steel pin. This is where the tendon fails. I was shocked to see what i had been sailing on. That crack you see running out from the screw is not normal, and it was only a matter of time before this one failed completely. I was literally one solid crash or dues paying moment away from being in a potentially bad situation. Phew, can't tell you how blessed i felt to have examined mine. Thanks Andy!

In fact, ALL THREE of my tendons where compromised! Fortunately, you can get a replacement tendon for about $10.

Take advantage of those non-windy moments (unfortunately those have been all to frequent as of late) and tend to your gear. More specifically, I highly suggest you take a close look at your universals, and if you use the Chinook tendon, take it apart and examine it closely on a regular basis.



Pål Rype said...

good you checked ! last year on Maui i derigged after a session in very offshore strong wind at Kuau and noticed that the Tendon was almost completely teared in two. 1 year old..

Andy said...

Yeah man glad we caught that... Pull them apart to inspect when the middle of the tendon starts to look "pregnant."

Anonymous said...

love it!Dont do repares whenthe waves are braking !!!

Ken K said...

Good catch. Think of that next time you are way on the outside! I use the old rubber hour glass U-joint. I buy a new one yearly and use the old for sound side sailing/ skateboards etc. The rubber ones show surface cracking when you bend them to give you a bit of warning but I stop using them in the ocean before they show that. I had one fail years ago, the webbing kept it all together although the exposed bolt end slid beyond my base plate and punched a couple holes in my board before I got back in.

Aaron said...

Checked mine as soon I read your post. Great info...Thanks

PeconicPuffin said...

Wow. I've never disassembled the uni to check (I always just bend them and try to peek inside). Will be taking my uni's apart this weekend. Great post!