Broken Catek

[Christian]

Hi,

I managed to destroy my Catek OS2. It happened 2 weeks ago. In the meantime I wrote 3 emails to the manufacturer without getting an answer. So I think its time to publish it at BOL.

I recognised the damage after my liftride up the mountain. My front foot felt a little bit strange and was really lose. It was to cold and windy to check it so I was going very slow down to some better place. After I removed the stepin receiver of the front binding I could see that the thick aluminium plate was completely broken at the last two holes on the left side. At home I examined the binding further and found another big crack at the right side and one at one of the tilting screws. So it was only a matter of 4 or 5 hard turns before a really bad accident.

The binding was from 2007 and I had about 20 days per season on it. I'm not as aggressive as some other riders, so I can't imagine why it happend.

So my warning to all Catek owners: Check your binding for such cracks!

Christian

PS: Fin, if you read that: Now I'm ready for some TD3 Sidewinder SI!

Some pics:

[durace]

That does not look like a Catek heel reciever. The reciever looks bent too. If that is the case bolting a bent steel plate to the aluminum could have stressed the base. Just an observation I could be way off.

Paul

[b0ardski]

That does not look like a Catek heel reciever. The reciever looks bent too. If that is the case bolting a bent steel plate to the aluminum could have stressed the base. Just an observation I could be way off.

Paul

Good point. Looks like the last 2 holes on the plate should bee avoided regardless of the receiver used.

[Christian]

Yes thats no original catek heel receiver, but the bomber heels. At some time Fin sold those especially as a replacement for the catek binding.

And no the heel receiver is not bent (in a way it should not be bent). It sat flat on the binding plate. Its exactly the same like the one for the td3 but with a little bit different slots placement.

Yes I mounted the heels in the last holes on the plate, because there was no sign telling me not to use those holes. I know the last holes put the maximum stress on that binding, but the holes are there not only for good looking.

By the way, my weight is 72kg (158lbs) and my boot size is M26.5

Christian

[pow4ever]

Good thing you are not hurt. That's the most important part.

I also have the bomber catek steel receiver for fin-tec but it's never installed.

Thank you for the heads up. I will check my catek before use.

Seems like you have the short plate. With size 26.5 boots you shouldn't need to using the last hole?

This is what I do but not sure if it's correct: I center my boots on the plate and try to even out the pressures.

If you just choose the last hole on the receiver side but use the 3rd hole on the bail side you might be putting more pressure than necessary.

You can use the last hole if you also use the first hole on the other end of the plate; hence center.

Hope the above make senses.

Best of luck.

--

David

[www.oldsnowboards.com]

Photo of the binding with the heel reciever attached please.

Sounds like it was too far out over the end of the plate?

If you have the other binding mounted the same way , perhaps a photo of it?

Glad you were not hurt.

With a small boot I would ask why it was extended so far out?

[molekulo]

If you use bomber reciever with catek binding, it is for your oun risk.

If bomber receiver's mounting holes have even a little misalignment with catek's plate holes, then the plate is under the extra unexpected load.

[Chris Houghton]

Must be OS2 small plates. I too am curious as to how the receiver mounted to the plate. Can we see the other binding fully assembled?

[KingCrimson]

Not to bring the OP's credibility into question, but either there was something wrong with the aluminum, or this is what the bike industry calls a JRA, "Just riding along" story.

Guys, keep in mind that's a cant screw with the crack next to it. It's not only the mounting holes that failed. I think this eliminates the Bomber heel piece or it's placement as the culprit.

That said, those outermost threads are scary close to the edges.

I can't imagine how the canting area broke. Is it possible the plate was ridden with a loose kingpin but super tight and well-divoted cants?

[Christian]

Just a quick update:

For pics, please wait a few hours, I'll take some today when I'm home again.

I did not ride with a lose kingpin. Always when I mount the binding, the first thing I do is to tighten the kingpin. For that I use an "L"-allen key. Then I tighten all four cant-screws another 1/4 turn.

The only thing I never did is using these black plastic rings on the kingpin. I know it is recommended to use these, but it worked all the time without. I had never a loose binding.

I know it was at my own risk when I mounted the bomber heel, and I don't ask Jeff for another binding or something similar but the least thing I expect is a small message from the manufacturer telling me what possibly went wrong.

Christian

[KingCrimson]

Correct me if I'm wrong, but I think the black spacers on top of the kingpin are weight bearing if you're using a lot of cant. If the plate wasn't actually supported by the kingpin from the underside, it makes sense the tilt screw cracked the plate.

That still doesn't address the issue of the heel cracking though.

[Christian]

@KingCrimson:

maybe you are right, then its completely my fault. But I don't use a lot of lift/cant (3 lift front, 4 lift back, a very little inward cant on the front)

@all:

Here are some more pictures. As you can see, the heel receiver is on its innermost position. I know it was completely my mistake to mount the heel on the last holes of the plate, but at that time I thought the ice breaker works better there (I now know thats not true).

On one of those pictures you'll see that my boot is only slightly of centered. Hmm but maybe that is still to much.

Christian

[KingCrimson]

You have a very nice lever on heelside to break that aluminum with the Intec pins(!!!) being outboard of the plate.

[Chris Houghton]

Exactly! Now if he drilled two more holes in the receivers so that the heels were secured with 4 bolts instead of two....

[Corey]

Meh, if those nice threaded holes weren't meant to be used then they shouldn't have been there. And I'd have a hard time telling someone that the stresses imparted by a TD3 receiver are any different than those from a Catek one. However, once I got replacements I'd run the receiver bolts one hole forward to reduce the chances of this failure.

What do people with bigger feet do? What are those outer holes for?

Someone correct me if I'm wrong, but isn't the whole point of the Catek design that the kingpin holds the top plate down and the 4 small screws hold the plate up? On the old Olympic Cateks I owned you tensioned the kingpin as much as you could against the center nut, which wasn't very much as the nut spun freely in the base plate. Then you tightened the 4 small screws to adjust cant/lift and to keep the thing from flopping around.

The kingpin should see no downward load - if it did it would just move downward and hit the board's topsheet as nothing is holding the spherical nut up in the binding's base.

[b0ardski]

Exactly! Now if he drilled two more holes in the receivers so that the heels were secured with 4 bolts instead of two....

I sure looks like the leverage of the receiver is beyond the end of the plate. Long plates would have supported more of the receiver and more than likely not failed. If your going to cantilever the receiver at the edge of the plate , a second pair of screws would distribute the forces.

[Neil Gendzwill]

However, once I got replacements I'd run the receiver bolts one hole forward to reduce the chances of this failure.

It almost looks like he has room to move two holes forward.

[KingCrimson]

[quote=corey_dyck;306954]

What do people with bigger feet do? What are those outer holes for?

Long plates.

Someone correct me if I'm wrong, but isn't the whole point of the Catek design that the kingpin holds the top plate down and the 4 small screws hold the plate up? On the old Olympic Cateks I owned you tensioned the kingpin as much as you could against the center nut, which wasn't very much as the nut spun freely in the base plate. Then you tightened the 4 small screws to adjust cant/lift and to keep the thing from flopping around.

The kingpin should see no downward load - if it did it would just move downward and hit the board's topsheet as nothing is holding the spherical nut up in the binding's base.

<table border="1" width="200"><tbody><tr><td></td> </tr> <tr> <td>Step 1: Place the OS2 o-ring where you want the center of the binding to be located. This step is very important. The o-ring is pivotal to the new Catek linkage. </td> </tr> </tbody></table> <table border="1" width="200"><tbody><tr> <td></td> </tr> <tr> <td><center> Step 2: Place the Spherical Nut on top of the o-ring. </center></td></tr></tbody></table>

I suspect your spinning problems would have been resolved to some extent if you had the o-ring.

Anyway, in regards to the receiver breaking, look at the Catek one. The holes are positioned directly above the screws in the aftmost position.

On the Bomber receiver in the aftmost position, the holes are outside of the screws by quite a lot. Also, the Bomber receiver offers a lot more adjustability, the Catek has barely any room to shift the receiver further out. Check out how far back the Bomber plate could be mounted if you were so inclined. This combination of design changes and an unlucky setup may explain the damage.

This also explains the odd boot centering.

[Chris Houghton]

If you run the short kingpin bolt then you could get away without using the black spacers, but you still need to tighten the center bolt before any of the cant screws touch the base plate. I always use at least one spacer as I don't want the king pin to touch the topsheet.

Torquing the kingpin against the cant screws is a no win - the binding plate will flex and the whole thing will come loose sooner or later.

[twelsch42]

Correct me if I'm wrong, but I think the black spacers on top of the kingpin are weight bearing if you're using a lot of cant. If the plate wasn't actually supported by the kingpin from the underside, it makes sense the tilt screw cracked the plate.

That still doesn't address the issue of the heel cracking though.

Those black spacers (not the o-ring on the top-sheet) are there to make sure you pick the correct (short or long) kingpin. This is important so you don't bottom out on your top-sheet.

T

[Kimo]

I may not be an engineer, but I know a stress riser (a starting/intial point for failure) when I see one and I see two in these pics. Both resultant cracks are identified by Christian in the two circles he included on the pics.

What I think caused the cracks is the inward tapered milling on the bottom of this (I assume) short plate. When the taper crosses the screw hole(s), a thin section of metal is formed and a stress riser is created and that's where the crack starts. For you aviation history buffs, this sort of like how the deHavilland Comet taught us that square windows are bad for pressurized fuselages.

I checked my OS2 long plates from a year or two before yours and there are no flaws like those on your short plates that would cause stress risers. My guess is it's either a design flaw in the short plates or a manufacturing flaw in your (and possibly other people's) plates. I can't guess what effect, if any, the Bomber heel receiver contributed to the failure. I'm leaning towards none, but the lighting does make it look like the contact area between the steel receiver and the short plate resulted in a disfigurement of the softer aluminum of the short plate. I just don't think that alone would cause this. I think it's clearly the stress risers.

Other notes:

Corey, I agree, if there's a pair of holes for the heel receiver, you should be able to use them. Otherwise, they shouldn't be there.

Crimson, I didn't catch what his full setup is, but, if he's got the D3 elastomers, he doesn't need the o-ring under the king pin.

Bottom Line:

Every CATEK user should check their plates for this flaw.