Windsurfing, surfing, Maui, The Gorge, and random rants.

Tuesday, February 15, 2011

A Univeral Solution

I just noticed that Rebecca found the perfect use for a broken universal. Love it!

OK, so after breaking my Chinook tendon on "Big Tuesday", I decided to search for a better system.  Below are some options I researched. On the right is my "all broke up" tendon.  On the bottom is a new Streamlined tendon with some mods (as explained later), on the left an hourglass with a separate two bolt plate, and on top is the remaining not quite broken but suspiciously crooked Chinook tendon.

A bunch of universals...

These all use the US cup which has a large metal clip with two buttons that protrude from the cup and connect to the extension.  The alternative system is the single pin "euro pin" base.  The euro pin base provides a more solid feeling connection and is much easier attaching and so on.  But I have some reservations about the euro (and not just the economy).

Over the past years I have witnessed some unintentional on the water disconnects involving the euro base (see picture of the Chinook euro base to the right).  If you look inside the euro extension you find a small metal clip.  This clip has a slot which is pushed against the groove in the pin by a spring hidden inside the extension.  All that really holds your rig onto the universal and therefore your board is a fairly small area of this thin clip - just the part that fits into about half of the groove in the pin.  I say half because in all the systems I've seen the metal clip is sprung from one side and therefore takes up only half of the groove in the pin.  I imagine it's just a few square millimeters of metal keeping your very expensive rig from Davey Jones's locker (my great uncle).  So a bit of wear and tear in this area and sudden disconnect syndrome can occur.

There are other potential failure points.  Should the internal spring ever break, lose its tension or get jammed then there is nothing keeping the clip attached to the pin.  This spring is contained inside the extension and on my admittedly quick examination I did not notice an easy means to access (to check it out) or replace this spring (not saying it's impossible, just hard to see).  Of course you could always purchase a new extension fairly often to ensure the spring and clip are all good, but these extensions are not cheap.  Also exposing your extension to sand or dirt could potentially jam either the clip or the spring.  And I believe this leads to the most common cause of premature euro pin ejection, at least in Maui.  You think you have a solid base connection, but a bit of grit keeps the clip from fully extending into the pin, so one big crash later and you are no longer at one with your board.  The scary thing is the connection probably feels solid right up to that point.

There's also a slight oops factor - the euro extension has a large easily accessible button which you push to quickly and efficiently disconnect the extension from the plate.  This is normally a good thing.  But I heard a rumor that some guy hit this by mistake while grabbing his rig after a wave take down.  New sails should cover the button but he had an older sail.  Possible?  Maybe.  OTOH - if you want to disconnect your rig on the water this makes it so much easier.

Having said all that I know many sailors who totally love the euro base and have used it for many years with no problems.  If you race then the euro system is the only respectable choice due to the solid and efficient connection.  But for sailing waves and rigging near sandy beaches it might not be the best option, especially if you don't replace your extensions very often (what, you're not sponsored?).

Hey, let's take a quick break and visit Little Beach courtesy of Moon Over Haleakala

Yet another very interesting little part of Maui...

So is the US base a perfect system?  No way Jose!  It's more like an old reliable car that somehow never breaks down even though it feels like it could at any moment.  I'm not aware of any disconnects that involved just the buttons and the cup itself, assuming both buttons were engaged all the way to begin with.  The most common pilot error with these is not fully attaching the extension to the base such that one or both buttons don't totally pop out.  You don't get the same solid "click" as with the euro pin, instead you must inspect both buttons and make sure they are really and truly sticking out, and do this every damn time you attach the rig.  But if they are out there then you should be good.  And it's very easy to inspect everything as nothing is hidden.

The main complaint with the US system is the looser extension to base connection.  It's never as solid as the euro system, even when everything is brand spanking new. And over time this play will gradually increase.  But again disconnects from the US base seem rare, perhaps because most people reasonably take any increased looseness as an obvious sign that it's time to replace all or part of the universal, which by itself isn't very expensive. And you can easily replace either the internal clips or the cup itself if you want.  The extension is a passive player in the US connection game, so you can keep it forever or until it breaks (hopefully not).  Usually I replace the whole universal once the cup feels too loose, and I see this as perhaps an unintentional advantage.  The euro universal is rock solid until the moment it completely fails, while the US universal just gradually becomes looser until it becomes obvious it needs replacing.

I've been using the US system since at least the early 90's (how long has this system been around anyway?).  Some of our extensions are at least ten years old (since we went skinny), and plan to keep using them forever.  Which is of course another reason not to switch - the "it ain't broken" rule plus replacing them all would be a huge pain. And very expensive (where's that sponsorship anyway?).  BTW - I'm not the only person who came to this conclusion. GP mentioned his preference for the two button US system in this post from almost two years ago.

But we did make a change which more or less led to our universal failure (which sounds so bad).  The picture to the left shows a Chinook hourglass with a two bolt plate.  We used this in the Gorge for years without problems.  I replaced these whenever the unis seemed loose and almost never replaced the plates.  But when we got our shiny new and oh so great Goya boards this fall, many folks suggested going with a single screw plate because: 1) cheaper (no need to buy a plate per board) 2) the two bolt plate to uni connection becomes loose over time, so the single bolt system should be stronger and tighter 3) the single bolt takes up less space in the mast track so more adjustments are possible.  4) Chinook tendons often only come with a single bolt plate around here for some reason.

The only disadvantage is the single bolt might not hold as strong as two bolts, and the single bolt puts more force in one spot on the mast track.  But since most of the pro sailors seem to be using the single bolt system I assume that modern mast tracks and construction are strong enough to handle the load.  There's also a slight inconvenience with screwing on a base instead if clicking into the two bolt plate, but NBD IMO.

The other change was going with a tendon over the hour glass.  Again many opinions on that.  I've never personally had an hourglass uni break before I proactively replaced it, but I know many folks who have experienced such frequent failures with hourglasses that they refuse to use them.  A lot of these guys sail here so I assumed that wave sailing puts more force on the uni and therefore exposes a flaw in the hourglasses design.  Therefore I switched to the Chinook temdon with a single bolt .  Now if I had read GP's earlier post a bit sooner I might have gone with the Streamlined base right away.  But I have been using various Chinook products for so long with no problems I had no reason to doubt the performance of the Chinook tendon.

What's odd about Chinook's US tendon base is the construction is so different from their euro pin version.  I know the US base must have been designed earlier, so I'm guessing when the euro base came along they decided to improve a few things - such as the euro tendon has metal caps instead of plastic and uses line for the safety instead if nylon straps.  If they went back and updated the US version all would be well but so far they haven't.  I guess they prefer to leave the older base as is, perhaps assuming most folks would go with the better designed (and more expensive) euro version instead.

There's also the problem that their tendon broke so soon - we only had it about three months, and the other unbroken tendon now has an obvious tilt such that I assume its days are well numbered.  Now in reality it's not so bad if a tendon or hourglass breaks, assuming this was the result of a large wave landing on the rig.  It's much better to break a base than something way more expensive like an extension. Plus you can sail back with a broken base, assuming - and this is important - that the safety lines hold.  And as you can see from my broken base, instead of safety lines it has have nylon straps and one immediately sheared off.  It was because only one marginal looking strap was left on my base that I ended up swimming (until GP came along that is).

So what's the solution?  Take a look at the Streamlined universal.  It's a US cup with a single bolt base, has metal caps over the tendon with strong  bolts, and most importantly it uses lines for the safety.  Also GP showed me a trick if you get this universal.  Replace the line it comes with with a stronger spectra line (down haul line).  I also added some extra knots to this line as you can see in the picture.  I'm not sure if this line is likely to break as is, but without the extra knots a cut in any section would have taken the entire line out.  So I added the knots as an extra safety - think of it as redundancy.  The knots mean each section of rope by itself can hold the base together.  And the cost and time to do this is trivial, especially when compared to the cost of your rig. Also, because I had them, I replaced the internal clip/buttons with the Chinook version as this will be connecting to Chinook extensions and their clip looked a bit stronger.

Before finishing this dissertation, since the subject is on things that might have broken, I thought it appropriate to link to our friend Olaf's story about one of his more interesting trips to Baja

So be safe out there everyone. And get yourself a universal solution if you don't already have one.


rebecca said...

a broken thingy just won't work. a bent thingy might be fun yet risky...I have two universal loves: streamline euro pin base/ext. though if the little adjustment ring isn't put on properly it'll wear wrong - seen this in rental gear but never my own. the safety rope wears because I use a volcano pad due to wimpy feet but that's easily replaced. my other ext./base is the np single button - love that thing so easy to use.

of course universal love is personal...

Anonymous said...

My first summer in the Gorge, I splurged on a new tendon mast foot.
Within the first month, I had compressed my mast track slightly from jumping and my board was full of water. The rubber joints have much better built in shock absorption and are gentler on your board when landing big jumps.

Anonymous said...

As pictured, the tendon joints usually break at the holes where you can't see that they are about to fail. It's easy to see a crack in the rubber joints when they are about to go.

Anonymous said...

This October I used a fairly new Euro Pin Base in some big waves at "Cold Hawaii" (Klitmøller, Denmark).
As usual, before starting the session, I thoroughly checked the base for correct connection!
After being washed by a big wave, the rig was separated from the board.
(And as I was not able to hold the board when being caught by the next wave, I had to swim back…)
Later I found both on the beach (board and rig), the base was still fully functional!
There might have been some sand in the system, as I broke a mast the day before on a sandy shore break.
Now I will probably change back to the US Pin system, but with a (high quality) hourglass. Because with the tendon you can not see if there is coming up a breakage soon. But you can check an hourglass for malfunctions.

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