FrankenTrab, This One is Almost It
Yes Virginia, I did it.
Y’all asked, I had to do it. Again, broken promises as in “I’d never try that!” This is simply a proof of ski touring binding concept. Please do not think you can pair these two bindings for a viable daily driver. In this configuration the actual release forces are unknown, and with this boot (an early Scarpa effort in cooperation with Trab) the side release at the heel bound up with the Kingpin rollers, though it did release to some degree. This does what many of you have asked about. It releases to the side at both toe and heel. More, you get what’s essentially an alpine heel unit (though you still have to step into a “tech” type of toe first, with the usual alignment fiddling). To the best of my knowledge the only other binding that releases fully to the side at both toe and heel is the “Knee” brand alpine binding. Check out the FrankenTrab, is this the future?
(Note, by “release” at toe I mean full lateral release similar to an alpine binding. Classic tech bindings do release somewhat at the toe, but are “blocked” from full lateral release of the toe perpendicular to the ski. Some “not classic” tech bindings do have adjustable release perpendicular at the toe, e.g., Vipec and Trab.)
Trab TR2 toe opens to the side in a way that allows the pins to ride out of the toe fittings. In other words, you can move the heel of the boot to the side with elasticity and return-to-center. This in turn allows the Kingpin heel to release to the side, unlike our experiment with using the Vipec toe. Both Trab and Vipic also have a mode that releases the toe directly perpendicular to the ski, as with alpine bindings. Key is we want a ski touring binding that does both: releases to the side at the toe — and the heel. This configuration does just that.
Heel of boot moves easily to the side at the toe fittings, allowing the Marker Kingpin side release at the heel.
Another view of heel in side release mode.
Marker heel places a large amount of force downward on the boot heel, which cantilevers the boot over the heel AFD. This created quite a bit of resistance to heel lateral release, an example of how this is only an experimental configuration.
View of how the Trab TR2 ski touring binding toe opens to the side for release.
All this begs the question, could variations of the tech binding provide the “safest” backcountry skiing binding in terms of knee tissue and leg bone protection? Perhaps the Marker guys need to make a trip to Bormio (Trab, Italy). Oh, and yes, I did ski them.
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Comments
29 Responses to “FrankenTrab, This One is Almost It”
Interesting Lou. I know you mentioned in one of your early write-ups on the Kingpin that Marker considered a rotating toe piece before going with a more traditional tech toe. Did they offer much insight about why they made that decision, or whether they will continue to consider side-release toes in future updates to the Kingpin?
Also, a bit of a non-sequitur, but what would your recommend for regluing a topspin that keeps separating from a ski? I have an old Atomic RT86 where the topskin has pulled back a few inches at the tip each season, despite an epoxy fix every year. Last month the topskin peeled back about 5-6″.
Thanks,
Tom
Having a spiral fx of my fibula last year I really appreciate you pushing the R&D of pin bindings. Hopefully the binding manufacturers are lurking. Not placing blame on any binding manufacturer but I am of the opinion (completely unscientific) that with my particular MOI I would not have broken my ankle if my ski had reliable release at the toe. Thanks Lou. If we ever meet…beer is on me. Cheers.
Hi. First, I gotta say, there are two Brunos who post on this site (Hi Bruno!). I’m usually the only one, so now I don’t feel lonely 🙂 More importantly, I love this experiment with bindings. Why not? To move forward you usually have to push the boat out there. I feel a sense of anticipation and some trepidation about a possible post from Rick…. If I understand correctly, the Knee Binding requires a left and right ski, probably to prevent pre-release. I’m guessing the Knee Binding only releases at the heel in one direction, but I really have not idea. If that’s true, then the problem with a binding like that above (assuming all the interfaces worked properly) would perhaps be pre-releases. But I’m glad you did it, if only to learn. Information = good. All best.
I have no idea why the TR2 doesn’t get more love? Especially with the Spectre 2.0 on the near horizon. Seems like it does everything (lateral toe release, alpine clamping of the heel, vertical and lateral elasticity, lightweight within reason) except offer a cocking toe/step in heel? Is that really such a deal breaker?
maybe biggest weakness is there isn’t a true “beef” boot supported? But wildsnow camp is usually in favour of svelt shoes.
How was he delta btw?
Pretty much neutral…. very nice. Lou
Dabe, thanks for pointing that out. I’ll try to give it more attention. Have to say I don’t like the TR2 heel entry system of having to hold it open with a ski pole. Reminds me of another brand binding model that started with O, both are A for awkward. On the plus side the TR2 heel has a very nice simplicity and sure holds your boot on the ski with good vertical elasticity. Thing about all this stuff is it’s fun to play around with but often ends up being a solution without a problem, depending on individual needs. Lou
This is not an impossible goal: bindings pivoting under the tibia instead of pivoting from end of boot have been on the market
first gen Marker MR alpine binding (moving AFD and turntable rear heelpiece) had a different pivot point than kingpin rear piece (MR pivot was more forward under heel) but otherwise acted similarly to the lash up Lou made
Salewa plate touring binding spun about the center point of the frame, nice pivot but no elasticity. Pre-released easily
The trick is having two pivot points for lateral release, one near the heel and one near the toe.
To oversimplify: pivot at heel is supposed to be better for leg bones, pivot at toe better for knees. Why? Start here https://www.wildsnow.com/15123/tech-binding-release-testing-acl-broken-leg/ and if that doesn’t explain it, ask Rick, because I’m still trying to figure it out myself.
Also Tom: epoxy and rivets.
Bindings with lateral release at the toe and heel do not have a good track record for retention (knee binding and Line Reactor).
I do not understand the fixation on this concept that allows the boot to slide out of the binding sideways rather than sheer out. To make it work without pre-releasing I would think your retention setting would need to be somewhere between 15-22 for most humans.
The King Pin heel still releases like a traditional tech binding. If I were to pair it with an alternative tie piece for added elasticity and durability it would be the Beast 16 toe.
On the flip side, if you could lock out the lateral release of the kingpin heel it could pair well with the TR2
I think the goal is not to have the boot slide out sideways (releasing at toe and heel simultaneously), but to have two modes of lateral release, one where the toe twists out (like an alpine binding) and one where the heel twists out (like a regular tech binding). How to make it work is usually the hard part.
I’ve been told a couple of things about lateral release at the heel, by at least 3 different mechanical engineers: Most importantly, they’ve told me that there has pretty much been no binding in history that had free pivot at the toe and lateral release at the heel, that did not have pre-release problems when used at chart settings. But none of those bindings had the tech style toe pins, so the jury is out on bindings such as Beast and Radical 2, which do have free rotation at the toe and side release at heel.
It was explained to me that the problem with lateral heel release is the forces you apply to your heel while skiing are sometimes virtually the same as the force that occurs when the binding should release and protect your leg. More, as many of you know, there is indeed a certain amount of “softness” you feel when skiing downhill on any binding with sideways heel elasticity. Most people get used to that and have no problem with it, but it does exist and bothers some skiers, especially those used to alpine bindings that grab and hold the boot heel.
The above is perhaps one reason why even classic tech bindings (those that don’t have a rotating toe) are problematic for some skiers when used at chart settings.
Give all this ten years!
Billy, it’s easy to lock out lateral release of Kingpin, for most people you’d simply crank the release value all the way up, that would virtually lock it out. A modder could also probably add some washers or something for even more spring compression, thus taking the max release value up into the stratosphere. Lou
What bindings had free pivot at the toe and lateral release at the heel but didn’t have tech style toe pins?
Oh, there were some plate bindings out there in the 1970s for example, with a simple catch at the toe that allowed the plate to rotate freely, along with all release taken care of by a mechanism at the heel. People tended to fly out of them… Lou
See,
At one point the Spademan binding was the largest selling binding made in America! No toepiece at all, and the ability to release in any direction. I had a pair mounted on my 215 Atomic SG’s (we are talking the Bill Johnson era). Don’t recall ever having had a pre-release and I did like the wind in my face. :wink
Not to say that the Spademan binding was the cat’s meow, and certainly not suitable as the basis for a touring binding. But there is more than one way to skin a cat!
https://en.wikipedia.org/wiki/Spademan_binding
I went through an extended telemark phase (releasables, no less). I’m all for freedom of choice. I never used Spademans, but, as I recall, they worked for a lot of people (including Bill Briggs).
See, just about any binding “worked” if the release setting was cranked up… Lou
Fair point, Lou. Like I said, I never used them. But, for some reason, this got me thinking about a test I think might be interesting using your toe spring test rig— what is the effect of locking the toes one, two or more clicks? Just in the interest of science. Warning! Don’t ski with your toes locked if you want the bindings to release! Skiing with locked toes can be hazardous to your health!
I don’t mean to suggest that such a test would be of any practical use. I expect the results would be fairly variable even for the same exact toe piece. But I have thought for a long time that a tech toe with a switch that would enable one to easily add, say, 4 release value units (e.g. 7 to 11) would be nice.
Again, it seems to me like the TR2 does the best job of any “tech” binding in emulating Alpine performance in terms of elasticity and releasability (vertical and lateral at the heel and toe respectively) but gets no fanfare.
Maybe it is because nobody wants an in-bounds tech binding (as Lou often says, that concept is a solution without a problem) but people seem to be pretty goo-gah over the kingpin for this purpose.
The promise of elasticity for in-bounds was the reason I bought em. (TR2s)
See, that test would have no meaning as not every tech binding has “clicks” and there is not any sort of calibration, as the “clicks” are simply there to take up slack to one degree or another depending on manufacturing tolerances. Thus, I could test one binding, get a certain value, then get a totally different value from another binding. It would honestly be ridiculous. Lou
Ridiculous, I agree, but it might be interesting. The test would need to be performed with a boot like the earlier version rig. I’ve got a dynamometer, so maybe I’ll just try it myself.
I did plenty of experimentation with that back in the days when skiers were constantly telling me they skied with “one click” or “two clicks” etc. Every boot and binding combo is different, and the binding lever on the the TLT, Speed Rad etc. actually has 5 notches, so it has what could be 5 clicks, and due to all the mechanical linkages those placing the lever on notch 3 on one binding is not going to be the same as notch 3 on another binding /boot combo. And so forth. Further, in testing you’ll notice that with some boot-binding combos, even pulling up to the first “click” sound essentially locks out the side release. There you go… (grin). Perhaps some skiers could somehow memorize the feel and sound of a certain toe lever position, which translated to changing the binding lateral release value from say, 7 to 9… but why not just set it on 9 if that’s what you want to ski with? Lou
Interesting debate on toe retention. Adjustable retention values for climbing might be nice. We do have tech bindings that have higher toe retention values. These bindings can be used by many folks for climbing without locking.
One of my concerns is when you get a heal release in a tech binding that has a higher (than traditional Dynafit ) release values on the toe; you are introducing unexpected issues. In cases where the heal releases vertically, but the toe piece does not, you are still attached to the ski.
While higher toe retention values will allow you a theoretical advantage when climbing (in case’s where a release is desirable), there is a “trade off”, and, I’m not sure which is best.
Thanks, Lou. I don’t doubt that your explanation is on the mark, of course. The reason not to just set it on 9 is that I think increasing toe piece clamping force reduces the type of pre-release I’m concerned about better than cranking up lateral rv at the heel (same theory as using stiffer/more springs). And 99% of the time a lower rv works fine for me, but on rare occasions when I might be tempted to lock the toe, some release functionality would be nice. And I’ve got some ideas about how to solve the problems you mention.
Sure, it would be easier to just buy some new bindings with stiffer toe springs, but what fun is that?
Regarding vertical release at the heel but still being attached at the toe: I’d be interested in knowing if any one with knowledge of the Vipec thinks this could be a issue. My understanding of how the Vipec works is that the boot has to rotate forward quite a bit after a heel release before the toe release is triggered.
Excuse the silly question… How do tech binding release in a situation like this? https://youtu.be/J-yZNoH2VrY