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Klint
19th February 2007, 09:36 PM
I've been using Streamlined's gear for years and think they generally make good stuff. However, I have some issues regarding the products I don't sort out myself.

Let's start with the tendon joint mastfoot. Before the season starts here in Sweden I want to check that the tendonjoint is ok and eventually repalce it. The screws that goes through the joint are rocksolid and are very hard to open/loosen up. Without ruin the screw head, what is the best way to get them apart? Do I need to push a phillips driver into the opposite screw when trying to get them apart?

Secondly, I'm considering buying a Redline extension. My previous Streamlined extensions are good but under heavy load, lets say 9.0 race sails the base of the extension becomes somewhat deformed. Hence, fitting to the mastfoot are in some cases difficult. Has the Redline series changed in any respect to come clear of this problem??

thanks for your help !


/ Andy from Sweden

Roger
20th February 2007, 01:32 AM
Hi Klint,
To get the very small screws that hold the tendon pin in a Streamlined joint, I've found the following tools really help.
A small vice (or a very small pair of vice grips) so you can hold the screw on one side while unscrewing the screw on the other side.
Get the right size Phillips screwdriver (a #1 I think is best) and if you use the vice, you can catch the OD of the opposite screw in the vice so you can really put some pressure on the screwdriver to prevent it from stripping out the Phillips drive.
Or, better still, use the vice on one side, and vice grips (just to break the locktite loose) on the other side. Then the screw will come out easily. Find some longer screws with the same threads and use a really long screw as a "driver or punch" to tap out the tendon retaining pin.
The problems with removing the little pin retianer screws are getting the locktite broken loose, and corrosion.
When you put them back together, use a little Never-Seize on the retainer acrews (lock-tite really isn't necessary) and you will never have any problems taking apart and inspecting them again.
I think the "deformation" issues of the previous bases have been taken care of in the Redline series, but I don't have any of the Redlines yet to make this statement form actual experience.
Alot of the "deformation" issues have to do with poorly fitting downhaul cranks and lever adapters, not so much with the Streamlined bases.
If you fit a Streamlined base, on a genuine Streamlined mast base cup, I've never seen a problem with "ovaling" the base. I have had some small craks appear in the outer tube from the bottom up to the 2 locking pin holes on the sides, but I've never had one break, even with the cracks.
Hope this helps,

steveC
20th February 2007, 10:38 AM
Just a note of caution. I was very interested in the Streamline Redline skinny mast base extension incorporating the Euro-pin receptacle, but I was trying to match a Chinook SS universal assembly as part of the plan. Unfortunately, no deal. Chinook's Euro-pin doesn't work in the Streamline base, since proper retention cannot be achieved between the two components. However, if one was to stick with the Streamline universal matched with the Streamline mast extension, everything is sweet. Streamline uses the North pin component (the standard), so the problem is truly with the configuration of the Chinook pin. Yet, the Chinook to Chinook combination works with no problem.

geo
20th February 2007, 02:46 PM
Personally I am still using the same WSH extension that I bought in 1993. Pity they seem no more available.

Just my thought. During my windsurfing experience, I sometimes happened to see people doing long swims in due to "Euro pin" failure. Since those parts are machined steel, failure is somehow a built in feature: no matter how thick, strong or "good" the steel, edges of machined metal may develope cracks and finally break under fatigue. This may not happen much often, but OTOH I have NEVER seen any US cup break and leave someone out at sea. I hope that the Euro pin will never become the standard.

Klint
20th February 2007, 07:03 PM
Thanks Roger for your valuable advice. One question though, what's the purpose of puting Never-Seize on the tendonjoint screws? Isn't this a lubricant, quite opposite to the features of Loctite?

If so, it's clear that the screws will come out easier when wanting to inspect the joint. But isn't there a risk with the screws comming apart while sailing?

thanks,


/ Andy from Sweden

utthita
20th February 2007, 09:41 PM
I think heat helps release loctite? You could try a hair dryer as it might not damage the plastic and rubber.

Ola_H
20th February 2007, 09:46 PM
Klint: I think you got good advice on how to get the screws out. Just a remark, when you have gone through the trouble of getting them apart, just go on and change the tendon while you're at it. Even it the tendon looks OK, there might be material degradation that you can not see. Comparing the low price of a new tendon with the often rather serious consequences of a tendon failiure makes this an easy decision.

Geo: I used to run the Euro pin and never had failures, but I have seen meny others that have. The problem is not the actual pin breaking, its the M8 screw inside (or the screw part of the pin when its one piece) and the most common reason is that the pin no being tightened hard enough. That said, have a look and Norths latest release or the current Chinook variant. Here the pin and the upper tendon fitting is one piece and I'm pretty this is a pretty much unbreakable system. I still run the classic cup system myself, but from an engineering point of view the new North system seem down right smarter than anything else to me. It would allow some pretty slick rdm extensions also.

steveC
21st February 2007, 12:34 AM
I've been dedicated to the two pin plastic cup design for many many years, but in the newer Chinook SS universal I saw an opportunity to go in a new direction. With the classic two pin cup, it has been my experience that the plastic cup component has a pretty limited life before it starts to get too worn and wobbly. Also, I've always had this consistent problem where one of pins shears off. Fortunately, this has never caused a complete failure, as the remaining pin seems to hold everything together. Still, because of the two pin cup's tendency to wear, I got into this rut of having to buy a new universal every year. Not terribly expensive, but still annoying.

I would have probably continued to buy universals yearly, but with a switch to skinny masts I needed to invest in new mastbase extensions. With Chinook's release of the SS universal, it was pretty much a no brainer to switch over to the Euro Pin and go in a new direction. From my perspective, the only point of weakness or wear would be the tendon component. Although the switch to Euro Pin would necessitate adding a retention plate assembly to the board, the advantage would be a more robust two point attachment to the mast track. Even though I never experienced a failure of the single point threaded twist-on universal design (where the SS threaded shaft breaks), I did have a brass T plate completely strip-out in the surf causing my sail assembly to separate from the board. Fortunately I was able to retreive my sail off the bottom of the ocean, but this still took some time and effort.

In going in this new direction, the one unknown I'm unsure of is whether I'm simply trading one wear problem for another. While the SS universal certainly appears bulletproof, I wonder how well the Euro Pin mastbase extension will hold up. I could be that the plastic base of the extension ultimately loses tolerance and wears out just like the two pin cup. In time, I'm sure I'll find out.

geo
21st February 2007, 12:50 AM
Two-pin cup may become wobbly, but they won't break. Plus, wear will clearly suggest it's time to buy a new one.
Euro pin systems are simply ill engineered. The screw part in one piece pins are the weakest because of the edgy machining of the screw, but anyhow machined metal will eventually develop tiny breaks that start major ones under fatigue.
In other words, an Euro pin may break, two pin cups just can not (unless extreme cases that I can't imagine but are still possible).
Of course, the occasional swim in is not an excessive trouble; and even less of a problem is for me.

Jean-Marc
21st February 2007, 01:07 AM
Roger wrote:
A small vice (or a very small pair of vice grips) so you can hold the screw on one side while unscrewing the screw on the other side.

Klint,

I'm not sure a bench vise is enough as a tool to grip the screw's head because on some Streamlined cups, these screw's heads are convex-shaped and there is simply not enough "thickness" for a strong grip to occur. Better hold the cup into the vise and unscrew with 2 Philips screwdrivers. A dab of WD-40 to unlock might be useful. Inspect the tendon for cracks around the screws + axis's hole (inside the cups) every year; I usually change the tendon every 2-3 years depending on usage.

Agree with Ola : Never broke the Euro pin itself, the sping nor the base, but broke the M8 bolt flush that was tightened inside the pin. Main problem was corrosion of the stainless steel bolt, right at the junction between the stainless steel pin and the aluminum cup. Different metal composition can give rise to galvanic corrosion; pitting corrosion of passivated metal such as stainless steel can also occur (both are enhanced by chloride ions of seawater). Even if rust is not visible, care must be taken not to trust stainless steel too thoroughly. Change the M8 bolt every 3-5 years depending on usage since the bolt is under extreme mechanical stress. Same mechanical stress put on the bolt that tighten a US cup with a tendon joint, BTW...

Cheers !

JM

Ola_H
21st February 2007, 02:11 AM
Geo: Here is an image of the "new" North design:

http://www.surfzone.se/forum/attachment.php?attachmentid=10042&stc=1&thumb=1&d=1135038221

(remove the linebreak after "?" when copying to your browser)

Just a simple one piece solution. I suppose its still machined but theoretically you could forge it too. Either way, I think it would still easily outlast the mast foot itself.

Klint
21st February 2007, 02:17 AM
Thanks for advices!

When assembeling the mastfot agian, should I use something on the screws to make them stick? Roger mentioned the product Never-Seize, but this sounds like a lubricant to me which implies the opposite effect to for instance Loc-tite. Lots of questions from my side, just don't want to be way out with a mastfot failure.

/ Andy

Jean-Marc
21st February 2007, 03:21 AM
Ola,

http://www.surfzone.se/forum/attachment.php?attachmentid=10042&d=1135038221

I agree a one-piece-single-metal machinated upper cup-Euro pin part will be better than a two-metallic-three-pieces assembly. Forging or soldering is bad because failure usually occurs precisely at the junction between 2 parts...

Klint,

I don't use any Locklite or Never-Seize stuff. Just strong tightening of the 2 screws on each interconnecting axis.

I just make sure all the screws on my gear are tight before each session (footstraps, fin, boom head and mast base/tendon/pin assembly).

Cheers !

JM

Ola_H
21st February 2007, 03:43 AM
JM: OK, I got the wrong english word then. Whats it called when you kind of "cold hammer" it to shape?

(And how did you prevent the link from breaking?)

steveC
21st February 2007, 03:53 AM
Thanks Ola H. for including the photo of the North universal, as I've never seen one before. I'm presuming that the SS component is machined from a single piece of SS. Although conceptually very similar to Chinook's variant, the solution is a bit different (the tethered plastic component). Also, the plastic component assembly on North's universal does hide the exact constitutes of the bottom assembly. Maybe it remains more traditional in nature integrating metal and molded plastic components together as an assembly.

In Chinook's approach, it's my understanding that they offer a single threaded screw (screw shaft is an inherent part of the machined parent SS component that attaches to the base of the tendon) as a design alternative to the pin type of attachment that I described in my prior post. Does North offer similar variants?

For geo,

While I wouldn't disagree with you in any way concerning Euro Pin designs if different SS components are assembled together to create a universal assembly, I'm inclined to think that one piece machined SS components are superior in design, and as a result, they greatly limit the opportunity for failure.

However, if the machined components do not include the proper stabilization and hardness processing, and particularly if inadequate radii at points of transition and stress are introduced, there is a much higher risk of stress propagation and an untimely failure. Ola H's proposed ultimate solution using a forged shape instead of machining from bar stock would clearly be the optimum way to go. Nonetheless, from what I can discern in Chinook offering, it appears that they have done an adequate job with radii on machined SS parts.

The thing that really disappoints me is that Chinook's pin configuration doesn't necessarily work between different brands (ie: Streamline mastbases). One wonders whether that variance was designed in on purpose.

Roger
21st February 2007, 12:05 PM
Hi Klint,
Yes, the Never-Seize is a lubricant and prevents galvanic corrosion.
I'm not sure if there's "lock-tite" on the little screws that hold the cross pin in a genuine Streamlined tendon joint or not, but I do know that I often find a little corrosion on the threads of the small screw, and there is often evidencs of a little galvanic corrosion between the stainless steel crosspin and the aluminum alloy of the cup the tendon seats in.
So, the Never-Seize is there to prevent all types of corrosion.
The way that Dave Dominy has set up the cross pins in the genuine Streamlined tendon bases, the cross pin does all the work, and has all the shear strength, the two small screws are just "retianers" to ensure that the pin does not fall out or shift off center.
So, lubricant is better here, as it makes the screws easy to get out when you want to inspect them next year.
Just tighten the 2 small screws nice and snug, and they will do their job of holding the much stronger cross pin in place, but since there is no stress or load on the screws they also will not fall out.
That's why it's important to get some really long screws to use when tapping the cross pin out. These screws should be screwed all the way in until they bottom out in the threads in the cross pin, so you don't damage or distort the ends of the cross pin.
Hope this helps,

geo
21st February 2007, 01:55 PM
Ola_H wrote:
Geo: Here is an image of the "new" North design:

http://www.surfzone.se/forum/attachment.php?attachmentid=10042&stc=1&thumb=1&d=1135038221

(remove the linebreak after "?" when copying to your browser)

Just a simple one piece solution. I suppose its still machined but theoretically you could forge it too. Either way, I think it would still easily outlast the mast foot itself.
Ola,

the design looks tough, by sure a great move from the usual two part with threaded pin that I see around. The threads were the weak point there.
By sure, this will be way safer. In this case, as any mechanical engineer will tell you, the weak point is where diameter abruptly changes from the "pin" part to the wider "tendon cup" part. Stress will concentrate there and, in case there is surface uneveness of any kind (scratches, corrosion, machining defects) fatigue will have its way. The bevel on top of the "cup" section will help for this, but not avoid it. Only, with such a thick part, it will take quite a lot of time for a crack to develope. I still can't see any reason to prefer this over a two-pin cup that simply is not subject to such issues. And that, I guess, is times cheaper and lighter.

SteveC,

that's the point: everything can be done, but...
Stabilization, hardening, forging, dealing with tapering radius and bevels... why? Why mess with expensive, heavy, complicated mechanical engineering to produce parts that have the habit to cleverly hide their integrity status, when you can have a simple plastic part that simply can not break (unless maybe it's so worn out that shows very clearly its state and you would never dare to use use it, and probably nevertheless it would never break even that way)?

These new parts seem OK, I guess the Chinook one is OK too, but a) in the meantime probably thousands have had to do the swim in, and 2) anyhow a simple inexpensive plastic cup will do the same job or better and be lighter and inexpensive.

Klint
24th February 2007, 05:05 PM
I did the mast foot check on my Streamlined and was quite surprised when noticing a clearly visible crack running all the way down the lower tendon retaining pin. The pin was also bent into a slight banana shape. Will have this replaced, just a matter of time before the pin would snap completely. No fun, especially if you go for longer cruises as I normally do. Suppose there’s an aftermarket for theses spare parts. Another weak part on the Streamlined is the screws that holds the pin which are out of rather soft steel and easy to ruin when undoing.

I also realized in case of a Streamlined mastfoot failure, the rigg would dance around on my Starboard wooden deck and eventually ruin it. This due to the single safety marlow line which is quite long. Think a better solution would be the one Chinook applies, with two safteylines which limits movement in case of a breakage.

If I’m now ordering a Chinook mastfoot with US cup, will this be a good match with my Streamlined extensions? SteveC implied that the Streamlined pin system will not work with Chinook. Hope this doesn't go for the US system. And finally, would it be possible to retrofit a Chinook mastbase with a Streamlined joint?

All the best,

// Andy

Ola_H
24th February 2007, 10:52 PM
Actually, there are two versions of US cup too, some are just a tad larger diameter (I think this applies to fx NP) but the difference is not bigger than some light tinkering can take care of. If I recall, Streamlined and Chinook are perfectly compatible though.

steveC
25th February 2007, 12:17 AM
Hi Andy,

I must emphasize that the incompatibility between the Streamline mastbase and the Chinook universal was limited to the Euro Pin configuration, and the source of the problem was Chinook's version of the Euro Pin. Also, just for the record, my Chinook Euro Pin universal was an early model that I bought when they first released the SS design. More than a year and a half that have passed since I bought the universal, and it could be possible that Chinook has corrected the configuration of their pin, so it would be prudent to check before you buy.

I doubt very seriously that there would be a problem integrating the two pin cup configuration components between Streamline and Chinook. Although I don't own a Streamline mastbase, I know that both the Streamline and Chinook two pin cup universals work well in my older Fiberspar SDM configuration mastbases, and also in a Gulftech skinny mastbase that I have.

Jean-Marc
25th February 2007, 03:47 AM
Klint wrote:
I did the mast foot check on my Streamlined and was quite surprised when noticing a clearly visible crack running all the way down the lower tendon retaining pin. The pin was also bent into a slight banana shape. Will have this replaced, just a matter of time before the pin would snap completely. No fun, especially if you go for longer cruises as I normally do. Suppose there’s an aftermarket for theses spare parts. Another weak part on the Streamlined is the screws that holds the pin which are out of rather soft steel and easy to ruin when undoing.

Yes, a once or twice a year quick check is not a luxury for your safety...

WRT replacement parts, I ordered mine from Murray Marine (5 tendon and 2 pin + screws) as described here http://www.murrays.com/archive/66-67.pdf.

I do have a Chinook base connected to a Streamlined 2 cups + tendon + Euro pin assembly. Neat since +5 years : no wear, no wobbling, no loose parts, no bent pin. By comparison, I broke a North race base assembly where significant wear and wobbling developped between the base and bottom cup after 4 years. The all-plastic-made North race base couldn't be disassembled (and bolts or tendon be inspected) in contrast to Streamlined.

To prevent damaging the woody deck of your hull in case of a tendon/universal failure, it's good to have a mast foot foam pad protection you can insert inbetween. Or use the foam pad boom bra if you use that.

Cheers !

JM

geo
25th February 2007, 03:50 AM
Ola is right. My Streamlined base does not fit my older WSH extensions. Silly thing.