Wednesday, May 06, 2009

mast feet (or foots?) + that one turn

As everybody knows, the two main systems are: the euro-pin and the double clips.
Most of the disconnected board cases that I am aware of, happened because the euro pin disconnected in the wipeout. That is enough for me not to use that system (I know there's plenty people who love it instead...).
In the photos from the left the products of the only two brands I know: Chinook euro pin and double clips and Streamlined euro pin and double clips.

So let's talk about the double clip ones. Both Chinook and Streamlined have flaws.
The Streamlined has the advantage of having the two terminals where the tendon is attached made by metal (I assume aluminum). That is great. In fact, you just have to replace the "normal" safety line it comes with, with a spectra one and you'll have a mast foot that will always let you sail back when the tendon breaks.
Tendons do break. Sometimes for intense use (they spend long time in the sun and that damages the rubber they're made of).
Sometimes they break also if they're brand new. And that's a great thing! If the impact of a wave is strong enough to break something, in fact, it's great thing that the tendon breaks (12 dollars), instead of an expensive extension or mast or board!
As long as the safety line is spectra and the two terminals to which the tendon is connected are still intact, you can easily sail back.
Tendons should actually be less strong, in my opinion. They would break more often and that would save a lot of money in replacing broken extensions and a lot of swimming time...

What's wrong with the Streamlined is that after a while the two holes through which the double pins pop out, become ovalized. And that's not a good thing, because the pins can bend at "unnatural" angles under strong pressure in a wipeout and that'll break your extension.
In other words, I like everything in a Streamlined foot, but not the plastic cup that hosts the clips.
The cup on the right shows the "unnatural" angle I'm talking about. The clips of foot on the left have a nice perpendicular angle instead.

Chinook is a mystery. They have a great foot for the europin system, with both tendon terminals in metal, but unfortunately the double clips foot only comes with those terminals in plastic. The safety line goes through some little holes in those plastic terminals (second foot from the left in the first photo). Guess what. You break the tendon and if the next wave is strong enough, the line can tear those little holes open like a knife in butter... and the board is gone.
It happened to me a couple of times and that's when I stopped using them.
But it seems that the plastic cup hosting the double clip is better than the Streamlined one. So I've been using a Streamlined foot with a Chinook cup for a while and everything is working fine.

Anyone out there at Chinook that would care for a double pin foot with metal tendon terminals?
Anyone out there at Streamlined that would care for a better plastic double pin cup?

Change of topic, let's talk weather.
Very unusual conditions for spring time. The wind is none or light and the waves are up. Monday and Tuesday were in the epic category for surfing. From Hookipa to Kanaha, Maui surfers finally have seen those glassy conditions that have been missing all winter! AND in the afternoon a light trade breeze picked up. That meant, for me at least, glassy surfing in the morning and light wind wave sailing in the afternoon. Cannot ask for more. One of my best couple of days in a row in the ocean ever. Sorry, no time to take photos.

Tuesday afternoon, in particular, I was on this logo high wave, as clean as it gets, and while looking down the line all of a sudden the memory of one of those combination of bottom/top turns that Polakow does at Backyards in The Windsurfing movie came up in my mind.
Couple of pumps on the rail to get some speed and... I did it! I did a bottom/top turn combo that felt just like those. Of course I'm sure it didn't even remotely looked like those, but it felt like them. And that was an incredible feeling. One of those moment that makes you scream out loud your stoke.
Clearly I didn't manage to do it again, but I know now how it feels and I will surely try to make it happen again...
Quick gear mention:
- 4.7 Ultralight Superfreak: phenomenal light wind wave sail
- 81l Quatro twin fin: phenomenal light wind wave board.

So long.


Fish said...

Great post. I've never really scrutinized them that much, but when you consider the role tendons and bases play, its worth paying a bit of attention to aging equipment.

While everyone has issues upon breakage, us canucks can consider ourselves f%$#'ed if we break one in December.

rathokan said...

Cup wear and the resulting looseness seem to be the achilles heel of the US Cup (twin-pin) system and one of the reasons I switched to Euro Pin last year. There seem to be a few points where the cups wear:

-b/w the bottom of the US Cup and the top of tendon cap. This area gets worn as the cup swivels during normal use and is exacerbated by sand, and the result is an overall looseness at the top of the universal joint (feels like the plastic cup is not screwed down tightly)

-the shoulder of the US Cup where the bottom of the extension comes to rest. This is also normal wear and tear, but it's essential that this area contacts the bottom of the extension and bears the downward load of your rig. As this area wears, the load starts to get transferred to the two metal connector pins, and these have been known to shear off when the wear gets bad

i have not really noticed the twin pin exit holes wearing down and ovalizing. Have you identified whether or not the Chinook and Streamlined pin clips are the same? The plastic cups are a little different.

The Streamlined 1-Bolt versions are quite a bit easier to tighten and un-tighten than their Chinook counterparts b/c of the bottom flange design.

Have you seen Streamlined Euro-Pins shear off? I haven't had any experience w/ this but I'm curious. Seems like there used to be a lot of trouble w/ Euro Pins shearing, but that most of these issues have been addressed at least w/ Chinook and Streamlined. One of the problems was that a lot of Euro Pins were being paired w/ plastic tendon caps which would deform under load and stress the connecting bolt. With solid aluminum or metal tendon caps, the euro pin has a much more robust platform and seems to be more reliable.

Dave said...

I had a disconnect with a pin system on a mast high++ day at Kuau.I had to swim after my board which was right side up and drifting rapidly w/ the wind. I caught my board after a nightmare swim sprint that left me totally gassed. After taking a few minutes to rest, I realized if I hadn't caught my board........Most scared I've ever been windsurfing.
That was in 2000 and it was a prototype a rep had given me to try out. Needless to say, he got some feedback. And he also replaced my rig I lost that day. I see that system as a death waiting to happen.
As far as chinnook vs. streamlined, I like them both equally. I've replace just the tendons before but now when it starts looking worn I just buy a brand new one. It really is the most important piece of equipment as far as I'm concerned.

Brian S said...

Good post on the shortcomings of mast feet. This is one component that surely could be better - especially since it has safety implications. I hope someone (at chinook or streamlined) is reading.
BTW, I do have a chinook cup in which the pins deformed like your streamlined cup. In my case, the holes for the pins weren't drilled correctly, causing alignment issues with the mast base. Maybe just a quality control problem?

Anonymous said...

Hi Giampaolo,

Good to see people do analyse stuff and don't take stuff for granted..

Don't know if you remember me, I did an internship last summer at HSM and developed the boomhead project...

Now back in holland I started to work on some different parts.. The joint and mast extension. This you say in you're post are pretty right.. europin seems to break once in a while, and us-cup has so much movement after a while. At the moment I designed a eurpin that shouldn't break. But that is just a idea. My graduation project will be this project. A new system (yes, it will be totally different). Why new? The market on the hardware stuff is sooo rusty.. People do take things and quality for granted..So good to read the last post.

Keep posting a lot, as I like to read it, and keeps me at the rock with my mind once in a while..


Anonymous said...

What about the universals with the boge tendon, seems like it would be much more durable. Also some have webbing holding the two parts together instead of just rope, which I think would be a better connection.

I use one of these, never had a problem with euro pin personally, and its a bit easier to attach and seperate cause I am lazy :P

ChinookR&D said...

Hey Cammar, I have made some custom SS systems for testing allready.

However the new system has NOT been failing at all! You need to check it out: more rope!


andrew c said...

I recently had a US Cup base break on me when I was far from land after getting rinsed by a huge wave.

The tendon broke and the safety rope actually ripped through the plastic, so board and rig were totally separated. I lost all my kit and almost got swept out to sea in a strong current.

I have since switched to Chinook Euro Pin, purely for the fact that they have an aluminium top and bottom, so that if the tendon breaks in future, at least the rope shouldn't be able to rip through the aluminium like it did the plastic.

I have had no problems with disconnect using the Euro, but that could be because I'm using a Streamlined mast extension, which has a plastic clip to prevent the UJ release button being pressed when in place.

cammar said...

Thanks everyone for the comments.

Rathokan, thanks for listing those other points where the cup wears.
I don't agree with you with the SL being easier to tighten - untighten. I find the Chinook plate way easier to tighten - untighten, since it has four ridges were you can apply pressure (I personally use three of them and that's enough).
Also a round cup will distribute the load of the weight of the rig in a more uniform way. I found that out one day while doing GPS recorded speed at Camp One. I had a good stretch of flat water and I pushed it a bit too far in order to get a good speed. At the end of the run, I had to cut across the reef and a lovely four feet vertical ramp suddenly popped up in front of me. No time to slow down, no way to avoid it: I jumped it. And what a jump that was... The landing was a bit harsh and the mast box sinked half inch into the board. I could sail back and notice that the SL flange was aligned with the mast box. That's a flaw. If the right tightening tension happens when the flange is lined up with the mast box, your mast box is in danger. This won't happen with the Chinook plate, since it's a circular plate. BTW, my hybrid foot has a Chinook plate too. Can't even remember how I managed to put one on a SL foot...
No, I haven't compared the SF and Chinook metal clips. Will do.

Dave, I hear you and I agree with you. Yesterday I quickly chatted with Pascal though, who showed me his Chinook europin extension. It looked pretty solid and he said that he never had a disconnection. But that's only his experience.

Brian S, glad (NOT) to learn that the Chinook cups deform too.

Jip, 'course I remember you. So, what's your new idea?

Anon and Caleb, I unfortunately saw a few months old Chinook foot (just like the one that Caleb links) in which the webbing was already wearing and tearing on the top end. I guess the webbing attaches in places too close to potential friction due to the rotation of the parts that are above and below it. The spectra line seems much better to me and it's virtually undestructable. In other words, sorry but I'm not impressed at all with that Chinook foot... definitely not shooting for sponsorship here :).
Question: why are the tendon terminals in plastic and not metal in the second foot from the left in the first photo? Will Chinook ever make one foot just like that but with metal tendon terminals? Thanks for taking the time to answer.

Andrew, yes those plastic terminals are a joke (sorry if I'm straight). Good that you're happy with the europin, but until I will keep hearing stories like Dave's I don't feel like switching to that system...

ChinookR&D said...

Hi again Cammar,

Thanks for the feedback. I had not seen the webbing wear issue yet. The part has only been on the market about 6 months so ... time will tell.

That said, there is a plastic washer in place as a friction barrier between the moving parts & the webbing. Maybe it wasn't doing it's job, or your friend has a very early model. Again thanks for the heads up, I will be on the lookout for this issue. Also should note that the new part has a thick oval cross section supporting the bolts. We have not had any issues yet.

Personally, I think aluminum is a bad idea for the tendon caps. Like I said, I have made some Stainless steel cup style extensions for testing, they work very well. However with such a low failure rate on the plastic parts, it may be hard to sell.

On the Euro Pin stuff, I have not seen ANY of our cast parts shear off & have not heard of any accidental disconnects. The only issue known to me(but not common) is with fine sand potentially clogging up the mechanism & jamming up.

Thanks again Cammar - keep it up!


cammar said...

Hi Caleb,
thanks a lot for your answer.
Stainless steel cup (oh, that's what SS stands for)... send me one if you want some Maui bound testing! But first tell me the weight, since I'm trying to keep the weight of my rig to as light as possible...

Why you don't like aluminum tendon terminals? And what metal are the Chinook europin (first foot on the lef of the first photos) tendon terminals made of?

ChinookRanD said...

The base "cup" is not Stainless on the prototypes but the tendon caps - which you called "terminals" are.

The Chinook Europin system is Cast 316 Stainless. The prototype simply uses the bottom "terminal" of the Europin system with slight modification to mate to the cup.

As for Aluminum: I feel that using it in moving assemblies in the corrosive marine environment is asking for trouble. It is relatively soft, so tends to wear at contact points & anodizing is quickly compromised - leading to the corrosion. In a part as small as those terminals, compared to Stainless the cost & weight savings are negligible, at least in a cast part. Engineering grade plastics have natural lubricity which lends itself well to moving assemblies & does not corrode. Of course, the parts have to be engineered properly for the materials.

What's your mailing address? I'll see what I can do.


cammar said...

Giampaolo Cammarota
PO box 791273
96779 Paia, HI


Anonymous said...

Hi Bras !

Living in Reunion with pretty hard conditions too, only one advice : leave the euro pin (break, get'll change for ever when it will happen to you ) even an old and moving US cup will still connect your board and will NEVER get off...(NEVER heard about it but plenty of time for the Euro Pin)

prefer the old diabolo instead of tendon they're stronger (less pieces), bigger witch mean less stresses on the base while receptions or ropes but a webbing holding and at least you can use them you change them like every two year just to be sure of it...

you know there's always a story about selling products...and people who buy new products...if you change your euro pin+tendon every year I don't think you'll have any troubles...if you want the old strong products not heavier which goes longer...

experience from pretty hard core conditions only in waves, believe me away from Euro pin and tendon...


benjaminpink said...

I use the chinook euro pin system. I've never had a disconnection but I did recently have my tendon break. It was one of the newer style chinook tendons and it broke up inside the top of the structure towards the pin part. I was sailing alone at natural bridges in santa cruz, and luckily it was on my first run out and only 25 yards from the beach. I was able to retrive all my gear and rig, which floated magically, and I towed everything back in through the surf using my life-guard sidestroke kick. I sent my universal back to chinook, waiting to see what happens with that.

cammar said...

as we said tendons do break. BUT, did the foot have a safety line (spectra?) or webbing? What happened to it?

Life guard side stroke kick... mmm, I got to try if it's more efficient than my inverted breaststroke that I do holding the tip of the board with on hand and stroking with the other hand.
Good website for swimming strokes:

Anonymous said...

Very interesting what I read here. I'm concerned about mastfoot durability for quite a while. My experience is the same as those of the guy from La Reunion Island.

I'm using the Chinook/Kinetic diabolo which I trust much more than the smaller european Boge joints or any tendons. Up to now I had only one failure in 7 years.

That was when a Kiter coming down the line crashed into me, while I was slowly going out. He hit me right on top of the wave and crashed into the foot of my sail. I could jump off just before he hit me. Luckily nobody got injured and he replaced my sail. But the strange thing was, that the Chinook diabolo joint (nearly new) was torn into two peaces and directly with it the webbing. At the impact my upright standing rig was pushed sidewards. The board didn't move much. So rig and board were seperated. Since this moment I'm no longer trusting in a webbing as a security line.

For me the best system would have the big Kinetic diabolo with a double lined spectra safety.

To ChinookRanD: Any chances to see this in the near future?