Hard-shell binding with rubber release, but not like Radars

[dchristman]

I'm looking for comments on my cabin fever binding design. Does anyone think this might have potential, or am I just going to hurt myself?

 

 

 

Note that I haven't actually ski'd on this yet, although I did do some jumping on the trampoline with it before a couple feet of snow covered it. Consider this more of a concept than something completely thought out.

 

I think this version cobbled together with (really!) old parts lacks the lateral stiffness I would expect with Reflex, FM, Goode (none of which I have ever tried, BTW). I envision a u-shaped bracket under the heel to provide more lateral stiffness and to perhaps give it a positive click-in feel with rounded detents on the bracket and shell.

 

"Why?" you might ask. Primarily cabin fever, but also because I really don't like the idea of moving to a binding that requires the maintenance of the current hard-shells or having movable, dangling, hard bits hanging from my ski. When I trick, I don't want to have to wear a shin-guard. I'd also like something less risky than the Approach bindings I've been slaloming with since 2006. Failing to heed the advice not to use them with an RTP, I did break my foot going OTF about the 3rd set out... then I bought the rear boot, DOH!

 

[mwetskier]

actually looks like a flash of genius to me -very clever idea but dont know if it will be secure enuff so let us know if it works or have someone else let us know where to send flowers.

[Chef23]

I am not sure it will be secure enough. You could probably put more on to cover over the toe and it might work. For the level of tricking I do it would probably work but I can't imagine you could flip on it.

[klindy]

One of the arguments away from rubber boots is that you have less "connection" with the ski in terms of edge control, etc. Modern Wiley bindings (Trick Wrap for example) have a LOT of rubber wrapped around your foot and ankle. Cutting away 90+% of that rubber so you can stick a hard shell binding into it would seems to hold your foot/ankle 'rigid' but still not translate that control to the ski. Perhaps that u-shaped bracket or indents would help.

 

I'd bet you'll have to add a LOT of rubber to what's in the pictures before you get something workable. By the time you do that I'm not sure what you've gained. I'd rather be able to "feel" my foot coming out of the binding (without the hardshell) rather than be surprised I've crossed the point of no return.

 

Nice thinking but I'll probably pass this round.

[dchristman]

@mwetskier - flash of genius - I like that! I feel better now. I'm not crazy.

 

@Chef32 - maybe not secure enough to flip with this prototype, but I think I will be able to flip on it, although perhaps not on the ski in the picture with this version 1 binding (but I'll try!)

 

@klindy - I know what your saying. I wouldn't want to add more rubber wraps (and a lot of extra weight) to to get more control. I'm thinking the heel piece could perhaps be a molded piece of rubber of varying thickness with the u-bracket molded in for support. The detents would contribute to "feel". If you have a silvertta clip, it is pretty digital - your connected or not. You pre-set the release point. With this I feel you would at least have a chance to recover if your heel came up getting you close to OTF. Think of it this way... it could allow for some heel lift if needed. I feel like it would get me closer to the decision point of continuing or not instead of letting the physics decide... mind over matter.

 

 

[Horton]

Could be genius or disastrous

[thager]

Kind of makes me think of building a jet with fabric covered wings. Have to kind of ask yourself why? Straight out the front looks like it would release OK but I would really worry about any twisting movement and the plastic materials binding against each other. Kudos for the creativity! Winter makes me nuts too!

[dchristman]

I'll be trying it on the trick ski before i try it on a slalom, as soon as the ice melts on the lake in exactly 29 days (unless I can't take it anymore and head south before then). It's hard for me to imagine a uncontrollable disaster situation on a trick ski. So it MUST be genius!

[dchristman]

@thager, why not? I think this guy is nuts, but I bet he doesn't think he is! http://upload.wikimedia.org/wikipedia/commons/7/7c/Dubai_Wingsuit_Flying_Trip_%287623583596%29.jpg Radar bindings don't release with twisting movement either....

[ral]

@dchristman, on the shin guard, what hits your shin is the back of the plastic boot when releasing from a Reflex, not a moving part of the binding. If what I see there is a plastic boot, you will face the same problem.

[MattP]

@dchristman interesting. Take video.

[thager]

@dchristman That's not nuts. Coming down the side of a mountain in that suit is nuts!!!

[scuppers]

@dchristman I thought it was a great idea - that prototype my not work but I think you're on to a good idea.

[dchristman]

@ral I know it's the boot to the shin with the Reflex release, I'm thinking that the dynamics of this release will be different so that you don't wack yourself in the shin. I don't think I kick myself in the shin when I release from a rubber boot, at least not that I noticed.

 

Aside from releasing differently the shell won't have the little block on the back of the heel to engage a release mechanism. If it does turn out that I kick myself with the boot, maybe I can give the heel of the shell some kind of soft, rubberized treatment to ease the pain.

[ral]

At low speed, trickers tend to hit with the foot on the binding, so they use sometimes a foam protection there.

 

I would say you have not noticed, I have looked at slo-mo replays of one fall (only one) with a big shin bruise, and the impact was not at the moment of the release but happened sometime in the yard sale afterwards...

[Waternut]

I like to encourage ingenuity but that sketches me out. I envision similar binding stability and hold to a cheap pair of combo skis when it's wet but without the feel to know when you'll come out. In my mind, the benefits of hard shells are comfort, predictable/reliable release, and excellent transfer between skier and ski. You have the comfort covered but the two important factors were missed. I think you're onto something but it needs more work.

 

I have a reflex and I don't do any maintenance to it during the ski season. I'm not denying people bash their shins but all of my bashings takes place when I slide over the ski after blowing the tail.

[eleeski]

I like to stay on the ski. Especially in tricks. I don't see enough hold down capability in your setup. Also that much rubber is heavy.

 

Still, that is a very creative idea with a lot of potential. Keep working on it!

 

Eric

[dchristman]

@MattP I started out to make a video tonight, but decided to have a beer instead - I know that may not go over too well on a video here. The design is still a little rough for a demonstration video anyway. I guess I could show that it is more stable than than @Waternut believes. I think he sees its heritage... I got the idea thinking about stuffing the boot into the binding of an old CG TrikMaster as a joke, but the binding wouldn't open wide enough.

 

As I said in previously, this prototype doesn't have adequate lateral support, but it's better than you think. The (at least) 25 year old boot certainly limits this prototype. The bottom isn't flat since it's off a skate boot - it has a raised heel so it needs something to fill that gap to make positive contact with the plate. I should have bought that reflex shell that @jdarwin had for sale. I think I'm going to squeeze a tube of shoe goo in there to fill the gap. I also think buckles might make it more stable.

 

@eleeski It's really not a lot of rubber - It's only 1/8" thick. I may add a little more over the toe as @Chef23 suggested just to tighten it up a bit more to reduce heel lift. Then I just need something to add the lateral support at the heel - some type of "U" bracket under the heel or maybe a heel cup molded out of something other than rubber, maybe similar to the extra heel rubber overlay on this binding:

 

[dchristman]

Maybe I should describe my thought process in coming up with this concept to diffuse the criticism of "not enough support". I didn't start out with the purpose of re-inventing the wheel.

 

The question I first asked myself was "How can I do a ski line back on trampoline, with a ski, and not hurt myself?"

 

First I ordered some surplus traction reels (I might need those later :-). Hmmm... I will certainly break something if I go out to the trampoline with a pot of water and some soap to get that rubber high wrap on... let's see what I have laying around the garage. Hey, maybe that rollerblade boot would fit in that old Cypress Gardens adjustable binding, that would be hilarious. Not enough support for what I want to do, but it'll sure be a hoot to try that at the lake, and it's got the latest hot green color! Darn, it won't open wide enough... maybe I can build something with another binding. How about that EP binding on my old Shortline? - I'll never ski on that again. The footprint of the boot fits inside of the horseshoes, easy to take apart, time to experiment!

 

Hmmm, this isn't too bad. I could actually ski on this! It just needs something to add more lateral support at the heel and a bit of positive click-in feel, and it might turn into the next big thing. It might be good on a slalom for a rear boot to allow for some heel lift. There are some smart guys on ballofspray, maybe they'll have some ideas. So here I am. I'm going to keep working on it, and I'll be back with a video when the ice melts.

 

Here's how I used the traction reels:

 

http://www.youtube.com/watch?v=0OOfoKCJSwY

 

It has to work - the prototype has great provenance. I used that EP binding the only time I ever slalomed in the regionals, I have an orthotic in it from the '82 nationals, and the boot has circled Okeeheelee in the mid 80's. I've ski'd on ping pong paddles with rubber bands for bindings, for cryin' out loud :-)

[dchristman]

oops - the missing image was supposed to be this video:

 

[BraceMaker]

Interesting concept - As you mentioned if it was a more rigid heel, the toe could be more like a reflex hoop. And you could use something like an O ring that would fail to hold the boot into a shallower rigid heel cup.

 

 

Where my mind keeps running is towards the Dynafit style Alpine Touring Binding.

 

http://www.sparkrandd.com/core/wp-content/uploads/2009/12/new-dynafit-3.jpg

 

 

[BraceMaker]

The reason I envision this is that the toe piece can release in several directions as it is two prongs that grab the toe.

http://media.dynafit.com/20131/08-0000048342_low-tech-race-auto/9170_red/_thumbs/3000x3000_48342_9170.jpg

 

Since the unit is at the toe and low to the ski - it isn't as likely to jump up and bite you.

 

At the heel I think it would have a static unit more similar to a hook/receiver, and the toe grab unit would be sprung so that it would slide forwards.

 

AKA - click in the toe, then push down the heel under the hook (pushing down would push the toe unit forwards)

 

Does it solve your mechanical issue - no... but would it be low profile to be unlikely to bite you in the shin? Yup, the back of the front boot can also now be more flexible/soft as only the sole would be mechanical. Problem with any sort of heel cup is that if your heel isn't trying to lift and you are turning you may get a good ol spiral.

[dchristman]

@bracemaker I think your getting my concept with your o-ring comment. I can envision is a rounded ridge around the back of the heel that would snap into a groove molded into the heel cup - the detent I mentioned in my first post.

 

I've been looking into what materials I might use to prototype this... maybe PCL for molded heel cup and Sugra to add a ridge to the back of the boot. Does anyone have any experience working with these materials?

 

Wow, those Dynafit bindings are pricey!

[dchristman]

... spelling correction - I mean't sugru: http://sugru.com

[dchristman]

Finally! The first skiing for the season yesterday. I tried my binding "as-is" just to see how it would work. I didn't try too much since the cameraman was also the pinman and I was a little tentative with the setup. It certainly needs some work, but I still think it has potential.

 

Definitely more comfortable than rubber, and my foot stayed warm - this old guy is sold on this hardshell thing regardless how this hair-brain idea works out. The main problem will be figuring out the right materials to get the right amount of friction between the shell and the rubber. While dry, the boot hangs in there pretty good. Wet, I could feel my heel sliding up and down. It didn't inspire confidence, especially because the heel rubber is so low.

 

The second issue will be the lateral stiffness. It wasn't as bad as you would think, especially given that the rubber is only 1/8" and the bottom of the shell isn't flat and mated well with the ski. To solve this problem, instead of th I think I'll try bondo, ala Mapple:

 

@Horton‌ - I came across your "magic bindings" post from 2007: ballofspray.com/forum#/discussion/8/magic-bindings

In it, you mentioned you had made a carbon fiber heel cup. Do you have a picture of that? Maybe that's what I need.

 

The cuff of the brittle, 30-year old shell cracked so I'm going to have to get a new one before I begin work on version #2.

 

Also, another plug for Camaro. I bought the Titanium 2mm over the winter based on the reviews here. Fantasic! The water temp was 53 and I was comfortable in the water and out of the water afterwards riding in the boat.

 

Here are a couple videos, just basic stuff (don't judge my ability on this). Of particular note at second 25 on the second video you can see the ski it still fairly perpendicular to my leg and it didn't just flop off:

 

 

[jipster43]

Great job by the pinman/camera man!

[eleeski]

Made me think... Rubber hold downs instead of Gatorade lids?

 

[dchristman]

@eleeski I'm not sure if your poking fun or serious, because I don't see how that works by the picture. I do understand how your gatorade lids work.

[Sherwood]

You can come to SMRR for some warm weather testing.

[eleeski]

@dchristman‌ Absolutely not poking fun as you really got me thinking and I truly appreciate your creative and fresh outlook.

 

This was just the start of the brainstorming session. My Gatorade lid system has a major defect - it takes longer than the allowed time to replace a released ski. I carry a backup ski in the boat so I'm not DQed if I release. You release and the run is over - even in practice. A rubber slip in system to replace the breakaway Gatorade lids could solve this problem.

 

Several details need to be addressed. The details of wing shape and materials, hold down placement and material selection will be a significant project. The picture was very premature and playing around afterward illuminated just how big a project this could be. Still, the potential for a 3D shaped wing that slides into a rubber hold down strap, could be engineered to slip out under severe load, reload easily and add minimal weight is worthy of investigation. Go for it!

 

Eric

[dchristman]

@sherwood I'd love to come down there to do some "testing", but I don't think that's going to happen this year. Vacations that involve skiing are now verboten. I don't get it... I've taken my skis along on every vacation the past 30 years, including our honeymoon. What's wrong with that? :-)

 

@eleeski OK, I think I understand what your envisioning. Your picture just looks like a couple pieces of rubber bike tube laying over your "wing" ends.

[Sherwood]

@dchristman‌ Well the great thing is that there are plenty of other activities to do nearby that you can get a couple sets in and still have time to do things with the family. Just sayin'. :-)

Austin and San Antonio are less than 45 minutes away. Not to mention the Hill Country. Plus with nationals being here this year you will want to get familiar with the site before the big show.

[gator1]

Hey @eleeski:

 

I always liked you frangible polymeric link multi-point release system. Light, doesn't mess with ski flex, simple, cheap. As I work on building new versions of the gatormod for Velcro plates I keep getting seduced into eliminating the Velcro with a design that replaces the frangible polymeric portion of your concept. I think I've got it. And since its not frangible you can get the plate back on the ski in the water. And easily adjust it for skier weight and ability.

 

I don't have time to work on it in addition to the mod. It appears you live a life of leisure in sunny CA. (perhaps that is just an illusion). Wanna collaborate?

[eleeski]

I'm really busy - living the life of leisure.

 

Perhaps some collaboration would be fun. The idea generation is fun.

 

Eric

[gator1]

@dchristman‌: Wanna play?

[dchristman]

@gator1 Well sure, that's what brought me here in the first place!

[gator1]

PM me an email address and I'll send you a sketch

[dchristman]

Exciting development (to me) from FM in single boot release systems. This is kind of what I was looking to do:

 

 

@lpskier tipped me off at regionals that Terence is also working on a new single boot release system. I spoke to Terence briefly about it - I'm looking forward to seeing that one, too.

[Chef23]

I saw that but after watching I am still not sure how it releases. Innovation is good though.

[BraceMaker]

Looks like the standard heel ledge has been replaced with a new version which is a bit larger/deeper. Based on the notes about compatibility with silvretta etc. the top of this heel ledge is likely set up the same as it would be on a Revo heel ledge w/ toe clamp system.

 

The Revo Air product had a similar aluminum cup to hold the heel in place with a ratchet strap that went over the heel block and secured the boot (for hands pass trick ski).

 

The release itself seems to be a rubber dowel that is held forwards into the rear of the heel ledge by a ratchet strap. The tension on which would hold the rubber into the heel ledge (which may or may not have a groove for which that dowel is maintained).

 

Actually kind of excited about this - hope he sells the heel ledge/release bit separate - I like the toe block Revo version - but am not a huge fan of silvretta release.

[dchristman]

My FM Revo Sub-Z is scheduled to arrive tomorrow. I'll let y'all know how it works!

[Glock]

@dchristman, please let me know your thoughts on this setup once you get it. I talked to Paul last week and am very interested to see how this works for folks.

[BraceMaker]

Also interested. I have a Revo I'd convert off silvretta.

[dchristman]

First, the bottom line - the FM Sub-Z accomplishes my primary objective of being able to use a hard-shell boot that is releasable without movable hardware dangling from the ski and I'm going to use it.

 

In the 2.5 years since I started this thread I finally succumbed to the siren song of the Reflex. I initially bought an older, used Reflex black setup to try on my trick ski. I quickly went back to rubber due to the pain and blood from the shin-banging characteristic. Since I wasn't using the Reflex on my trick, I ended up putting it on my slalom because it would allow me to go back to using a RTP. I hacked up the boot and really started to like it. I ended up buying a 2nd Reflex as a backup and to make it easier to try other skis.

 

This summer I decided to try the Reflex on my trick again since I had the 2nd unit. The second one I got came with a newer black boot and a thicker Intuition liner. I really liked the feel of this one on the trick and decided that was what I was going to stick with for the time being and committed myself to wearing a shin guard for both slalom and tricks.

 

Even though I was now using a Reflex, I still wanted to come up with an alternative that didn't require the shin guard. I started collecting materials to put something together... I bought some stuff and @gator1 sent me some bits. I'm not a mechanical engineer and it's probably a good thing that I lack the necessary tools to create my envisioned "system".

 

Enter the Sub-Z -

 

I received the unit last month and mounted it to my trick ski. My initial reaction was what others have said just looking at the videos that Paul made - "it comes off too easily". I had the heel strap tightened as tight as I could get it, but similar to how my experiment worked when I started this thread, it felt firmly attached when dry but wet it came off entirely too easily. (note that Paul's instructions do suggest testing the release while wet). I could easily pull the boot out of the release while skiing and put it back in:

 

 

I was able to carefully do some wake tricks, but just a little out of kilter and I was swimming to retrieve my ski. There was no way I would have felt comfortable trying it on my slalom.

 

I let Paul know how it (wasn't) working for me and he suggested maybe I needed the bigger heel block. The boot shipped only with the "standard" heel block. Paul says the release with the standard heel block is equivalent to somewhere between a 3 and 4 on the Silvretta. I was using a setting of 4 on both my trick and slalom, and I think 4 is maybe a bit light for tricks but workable for what I was doing - definitely not high enough for flips. Full disclosure, I haven't landed a flip in years. A hard-shell is part of my equation for changing that. I felt the potential when I first tried the Reflex, but I wasn't going to endure the associated shin damage.

 

Paul sent out the bigger block and some other spare parts, which I received this past Saturday. I immediately put the bigger block on the boot and gave it a go on my trick ski. Much better. The boot felt more locked in, but still released easily when I expected it should. I tried a few flips without the ski coming off, and I'd like to report that I made the first one that I tried (but I can't :smile: ) It was so much better than with the small ledge it gave me the confidence to try it on my slalom. I tried some slow passes at 28 and 32off (passes that I'm currently working on, so certainly subject to imperfection) and I didn't have any sense that I would suffer from a pre-release. I didn't have any falls where it released, but I would not have expected a release in those cases with the Reflex either.

 

Pro - no shin-banging Silvrettta!

 

Con - imprecise release adjustment

[dchristman]

oops. Premature post... I was about to add more words to my pro and con and accidentally submitted. I'll add some more detail later. I really need to get some work done to pay for my ski stuff!

[OldboyII]

Having this in hands - what do you think: how it may behave in type of crush where ski is goes "helicopter"?

Would it release?

Isn't there too much of side support?

[dchristman]

@OldboyII Not sure exactly what type of fall you're trying to describe there, but think of it as replacement for a Silvretta. The heel releases in an upward direction off the ski. No, it's not going to release like a MOB or other pin release system, and I don't care. I got this binding primarily for my trick ski where I don't believe multi-directional release is necessary or even desirable.

 

That is seems to be working well (in the ski-ability sense) for me on my slalom is a bonus. I haven't had any falls yet on the slalom that were sufficient to cause a release. My trust that it will release when necessary is based on how it released for me on my trick ski - who knows, it may not release when I really need it! At this point I would say I have about the same level of trust in it as I have in the Reflex on the slalom - I don't trust it completely, but I trust it enough to use it. I'm skiing cautiously and developing the trust.

[Nando]

dchristman, how is it working out as far as duplicating the tension? Did you mark the ratchet or is it easier than that? Could you post close-up photos of the heel piece? It's lighter than the regular Fluid Motions, but it always seemed like the weight of their system came from having really heavy boots- can you compare the weight to a reflex? Also, in slalom (unlike in tricks) the shin damage seems to come not from the Silvretta, but from kicking yourself during the fall- I know that's how I got the huge bump & bruise on my shin that I'm wearing now...

[dchristman]

@Nando here are a couple pictures with the standard heel ledge on the boot. I had the strap tightened as far as I could physically manage and it released too easily for me with the standard heel ledge. With the bigger ledge I have it, as best as I can describe, tight-without-forcing-it and it seems to release just right for me.

 

Sorry, I can't give you comparative weights right now as I left my stuff at the lake and I probably won't be back until Sunday unless the weather forecast changes. Without weighing them all I can say is that weight is not a noticeable or distracting factor.

 

 

 

I can assure you the shin damage I have experienced from the silvretta is not from kicking myself with the boot on release from the slalom - I am perfectly capable of crushing far enough for my shin to contact the silvretta without releasing and continuing to ski. Maybe that's not a problem for those with longer legs or less ankle flexibility.

[Nando]

Thanks! It looks like a great system for stability, not so much for any kind of twisting release. My shins seem to take a beating every time I go out the front, as the Silvretta releases then my R-style and the front boot goes right back at my rear shin. Solution- quit wit the OTFs...