Streamlined Universal Joint failure

jayturcot · Joined: 08 Mar 2004 Posts: 84

So on my season opening session, I had my Streamlined u-joint fail, with the upper and lower portion of the base separating.

Normally I wouldn't say that such an occurrence is post-worthy, but in this instance my normal preventative maintenance wouldn't have helped me... the failure was in a metal component and is not visible. Also concerning is that the back-up spectra lines, which would keep the rig attached in-case of a tendon failure, would have done nothing in this failure. Luckily I was right by shore in Half Moon Bay habour when this happened (vs. 3rd, TI or under the Golden Gate).

Model: Screw on (single-bolt), euro-pin
Bought: April 2014
Usage: ~100 days

Since the first day I got it, I notice there was a bit of play/slop between the the upper portion and the lower portion, but was assured that this wasn't out of the norm. Not sure if this is symptomatic as I've felt other streamlines with the same bit of play.

Through my local dealer (SunsetSailboards) I was able to get this base warranty replaced because Streamlined viewed this particular model/year as having a design flaw. I'm apparently the 2nd in our circle of windsurfing friends to have this happen.

Thanks to Streamlined/SunsetSailboards I got the broken lower replaced free of charge. Joint is like new and is rock-solid. Takes all of 2 minutes to do and I'll let SunsetSailboard comment on how to do it, but I think it's as easy as popping the tendon and the spectra line and screwing on/lacing up the new bottom.

How do I identify?

The base that had a bad design has a metal plate on the bottom with 4 holes in it (see below). My new bottom looks solid black (no metal plate on the bottom).

U2U2U2 · Posted: Tue Mar 29, 2016 7:11 pm Post subject:

Several things.
Certainly happy that you are ok.

Pleased that Kevin was able to help with the warranty.

I think you presented the breakage in a good manner, and were correct in doing so.

I have had problems with single bolt bases, I found the 2 bolt Streamlined works , with adjustment just slightly less than a single.

jayturcot · Joined: 08 Mar 2004 Posts: 84

Indeed U2U2U2!

In hindsight I was used to having a base to share between 3 boards. I should have just bought a single top and 3 2-bolt bottoms for my boards, especially since I use my freestyle board 80% of the time and never change where I put the mast track.

As for the base, Streamlined really did step up IMO and (I believe) they are willing to swap out the bottoms for any of the 'bad design' single bolt bases, even if they aren't broken, which was the primary motivation for me sharing. I think I stripped the threads on my other base and will stick with Streamlined for the next one.

Just thought I'd share because the though of gear failure far from shore is a scary one!

joethewindsufa · Joined: 10 Oct 2010 Posts: 1190 Location: Montréal

breaking a mast base has too many ramifications Confused

PITA when far from shore
but even worse have seen people bash their boards from coming in with broken tendons Sad

because i use large sails , i use the two(2) bolt attachment and mechanical mast base = NO ISSUES

techno900 · Joined: 28 Mar 2001 Posts: 4161

By the way, for those that do break tendons on the water, it is no piece of cake sailing in with the base sliding off center about 3 inches while still attached by the webbing.

I was in dying winds on a 105L board. The base kept moving to the windward side of the board, which caused it to head up, so I couldn't hook in. I wasn't able to get it to bare off and was half way between planing and slogging. My arms were shot after a 1/4 mile and three water starts, so I flagged down a passing boat and got a tow for the last couple of hundred yards.

Check for cracks in those tendons! Although not damaged, now there is a dent in the deck of the board.

isobars · Joined: 12 Dec 1999 Posts: 20935

LeeD · Joined: 12 Jun 2008 Posts: 1175

Yeah, Streamlined and Kev are good people.
Cure is longer bolt for more bearing surface and more locktite on more threads.

gregnw44 · Joined: 23 Jul 2008 Posts: 783 Location: Seattle, Wa

Yes jayturcot, this is an important issue. I had the same thing happen to me, 2 summers ago. The hidden connecting bolt broke, between the U-joint and the bottom piece. The U-joint has safety webbing, just as your tendon has line... which will keep the rig attached to the board, in case of U-joint failure. But there is no safety leash to keep things connected, if THAT bolt fails. Mine was a mastbase from a production board company. The same thing happened to me, as you. The rig and board separated. It was just luck and fast swimming, that I caught the shortboard before it blew away too far. Then paddled back to get my rig. I thought about leaving the rig, or de-rigging it... but in either case, staying with the board, and paddling back. But a boat came by and brought me, the board, and the rig back to the beach.
I got a new bolt form a shop, and threaded it back together, with lock-tite.

A couple people here mentioned they use 2 bolt bases, like they feel safer, implying this won't happen to them.
But why are those safer??
The base didn't come unscrewed from the board.
The bolt between the U-joint and the fitting broke.
A 2 bolt base also has a U-joint that attaches to it. If the bolt breaks which holds the U-joint together... then you have the same problem!!
Right?? What am I missing?
For the failure, we're talking about here... it doesn't matter if you use a 1 bolt base or a 2 bolt base... right?
Thanks, Greg Smile

joethewindsufa · Joined: 10 Oct 2010 Posts: 1190 Location: Montréal

guess i just have a hard time thinking this will break
but who knows - anyone, anyone ??

then again - this does NOT even have a safety rope
maybe NEVER needed ?? Very Happy

gregnw44 · Joined: 23 Jul 2008 Posts: 783 Location: Seattle, Wa

Yes, that kind of U-joint can definitely break.

There are 3 kinds of U-j's -
* rubber hour-glass
* tendon
* mechanical
And all 3 can break. I know of two people, that had mechanical joints break.

Modern rubber and tendon U-j's have either, some webbing or a piece of downhaul type line, connecting the top and bottom of the joint. This works great, to keep your rig connected to your board, in case of U-j failure.
And some mechanical U'j's similar to the one pictured (I have a Fanatic brand model) also have webbing connecting the top and bottom, in case it breaks. But the one pictured, does not have this safety item.

Anyway, that's all good info... but the issue of this thread, is what if the hidden bolt breaks that holds the top or bottom of the U-j to the next piece, breaks???

In the pic of the mechanical U-j for example, there is a bolt that holds the bottom of the joint to the "pin". And there is another bolt that holds the top of the joint to the "cup" on top.
Either of these bolts can break!!
Which is what happened to the OP and me.
And when that happens, your board and rig are NOT connected anymore. If your board gets away from you in this situation (which happens FAST in high wind or waves) and you can't swim fast... you could be in very BIG trouble.

For those who like to sail in hi-wind... and or, like to sail off on big adventures farther from your beach than you can swim... THIS is a big issue!

Do we need to go back to the 80's... when all the boards had built in safety leashes?? It was a bungeed line that came up out of the mast track and connected to a swivel up under the sail.

Thoughts, ideas, suggestions...