Classic WildSnow modshop crazy-ness. Take it as you will. First concept: Scott Cosmos III is VERY nice (available fall 2017). Second concept: Scott Cosmos III does not include cuff alignment. Third concept: Cuff alignment, as witnessed at Atomic FIS shop and as many of you readers know, is valid. Fourth concept: Atomic Backland and Hawx reversible cuff bushings will be available as a retail SKU. Fifth concept: We have the tooling. Sixth concept: We are bloggers. Enjoy.
Yes Virginia, this is a somewhat virgin (skied once) Cosmos 3. I like these boots. External lean lock, fit my feet (with a few tweaks), probably a 125 flex. Easy on and off due to tongue shell construction. But dang, the cuff alignment rivet present in version 2 is gone. Not so much of a disaster, actually, as those things are problematic (they move, come loose, etc.). What’s better is to simply drill the cuff pivot-rivet holes where you want them so the cuff aligns with your lower leg bone — otherwise known a the tibial shaft. Like they do for World Cup racers at Atomic in Austria. And we do here at WildSnow dot com in podunk Colorado.
Key to using Atomic ‘Frictionless Pivot” system is this little guy. Purchased from igus.com,
this is part number MSM-0912-14, iglide M250 sleeve bushing, shortened to match Atomic T-nut. What makes this all work is the diameter of the M250 is greater than that of most boot pivot rivet holes. (Modder beware, however,some boots might require more extensive modifications than those shown here for the Cosmos.)
Regular cant rivets such as this one from Scarpa move your cuff up and down by about 2 mm, or in this case 1.83 mm to be exact, thus changing the right-left angle of the cuff. That means that simply offsetting the rivet hole in the boot shell by a bit more than the bushing wall thickness of 1.67 mm results in an cuff alignment tweak that’s entirely adequate for most people needing this sort of thing. If you want more, you can do this mod on both sides of the cuff (though doing so could compromise operation of the lean lock, so take care).
Smaller hole will be ‘egged” then cleaned up so the bushing ends up offset from original pivot center.
Atomic ‘Frictonless Pivot’ donated from another boot for now, we’re waiting for a few sets.
Boot fitter tooling moves the cuff so we can access OEM rivet hole. Removing rivet is perhaps the hardest and most time consuming part of these operations. A large burr grinder works best, cooled with water spray. My method involves drilling it out, again with water cooling and a few tricks to stop thing thing from spinning.
Egged hole has been cleaned up, shown with bushing and T-nut inserted. A 15/32 step bit seems to work well for final tuning of the hole, after egging with a rotary cutter bit.
Atomic bushing installed. At this point the system often goes together in minutes, but the process can stall if boot shell and cuff thickness make the OEM Atomic system need mods (problems could come up if your boot shell plastic is significantly thicker than what the Atomic system is designed for) . In this case it all fit together perfectly. Once you know everything works, assemble with blue Loctite, but of course.
Hole in the cuff is enlarged to 16 mm, again with a step bit.
Final assembly is easy. Again, remember to Loctite. If things don’t go together the way you think they should, you might need a longer screw or an extra bushing to space the cuff away from lower boot shell.
Note, some boot models have built-in positive cuff angle, others do not. Before obsessing on tuning your cuff angle be sure to evaluate your actual needs. You might need nothing, or at the most a small amount of thickness added to one side of the liner cuff to match the curve of your tibia.
Related Links
Install a cant rivet, works in some boots.
33 comments
Do you guys keep a master list somewhere on site of boots (AT or otherwise) that have adjustable canting/cuffs?
No list, very few and less all the time it seems. Another reason not used is tilting the cuff can make the lean lock not work. Lou
Would the B&D retro rivet accomplish similar results?
How much Cuff angle does the Cosmos by default have, compared to, say a Dynafit Zzero?
Sedge, if the installation of the B&D pivot requires enlarging the hole in the scaffo, then yes, you could do a similar procedure. I don’t recall if the B&D requires enlarging the hole.
Daniel, Cosmos has zero cuff angle, measured with large carpenter’s square with boot on flat surface. Cosmos does have a nicely designed spoiler inside the cuff that’s biased to the side, but presumably could be reversed. Just this alone is probably equivalent to at least a 1 mm cant adjustment at the pivot point. Most ski touring boots have little to none — which makes sense since some people are knock kneed and some are bow legged, so you can’t really default the boot one way or the other without troubling someone’s skiing stance. I just looked at TLT6 and it appears to have a bit of cuff angle built in, which might be why it’s so liked by some people but disliked by others. It doesn’t take much for a cuff angle correction, as the amount is multiplied by the height of the cuff. Like I’ve said, the correction can often be done by simply adding some material to the liner cuff on one side, or even biasing the boots while heat molding, by paying attention to how you’re standing. The Atomic Memory Fit shell plastic is said to lend itself to this type of heat alignment.
All that said, quite a few boots have a sort of “anatomical” shape to the cuff that’s designed to help match the normal shape of human leg bones. This can appear to be a “cant” angle on first glance. But again, most boots when checked with square are pretty much neutral. Some people clearly benefit from adjusting cuff angle to one side or the other. While most people probably don’t need it or won’t notice any difference.
Lou
Cool Lou, and gutsy – I would be freaked out about doing this to a new pair of boots for fear that I would damage the boot or mis-drill the hole and still end up with the wrong cuff alignment. I would have been worried that the biggest problem would be that the female side of the Atomic bolt would be too long (that the Atomic boot walls would be thinner than the Scott walls). I guess in this case you could have ground that part shorter. Its amazing that the wall thickness of the two boots were similar enough that this worked out perfectly. It does seem to me that it would be safer to install an adjustable bolt from another manufacturer. Perhaps a company like B&D can begin making these since so many boots now seem to lack cuff adjustment.
Does the bushing seem to be made of some sort of special material? Did you have difficulty finding something with the correct I.D. and proper O.D.?
Tom, the extra bushing was easy to source. It’s made from a type of nylon that’s supposed to be super good, but it’s not a big deal as I’m pretty sure it’s the other bushings that act as movement surfaces.
Smaller nylon bushings are easy to press fit, and when you do so it can increase the diameter, this allows fine tuning. With this project, the bushing I ordered fits perfectly and didn’t need any tweaks other than cutting it to length.
Remember that these posts are more along the lines of a “proof of concept” then they are something we’d recommend tackling.
As for different boot shell thicknesses, in most cases that can be compensated for but not always. In my case, I can pull a rivet and if I don’t like what I see I can re-rivet as I have a boot riveter. But any lighter Grilamid boot is going to be quite thin.
If a boot fitter got serious about this, bushings and fasteners could probably be sourced that would work for nearly anything. And we have Bollinger’s solution as well, which if the demand was there could be made into a system that would cant the cuff.
The key item is the aluminum hex-head T-nut, which I’m pretty sure is made specifically for Atomic, but I could be wrong.
Lou
Hey Lou, where on this site are all those fantastic boot dimension measurements you were doing? I have been playing with some different boot models and hoped you had some beta on inside heel widths. I have very narrow heels and getting a good heel fit is key++! My TLT5s have been great but are ageing and the TLT6 is a bit bigger in the heel so I am wondering if there is any hard data to compare boots. I usually use a size 27.5 shell.
And, yes, believe it or not, I found good spring skiing on the west side of Mt. Mansfield, VT last Sunday in the woods. It’s going fast though.
Hi Herb, that used to be here:
https://www.wildsnow.com/more/backcountry-skiing-boot-dimensions/
I defer to Skialper magazine and bootfitters.com, one can only do so much (smile). But I’m not sure how much they give in terms of heel dimensions.
Good to hear you got spring skiing up there! Colorado is amazing right now, people are just going everywhere, doing everything in sight. World class stuff going down in terms of ski mountaineering, but it’s not Chamonix so it’s under the radar (smile).
Lou
I’ve come across so many people who simply look at you with a blank stare when I mention that proper canting and alignment are more important than what skis you have under your feet that I usually relegate the topic to the “never talk about politics at work” drawer.
Alignment starts at the bench with analysis of the individual foot structure. After the foot is stabilized with a custom built footbed and the ramp angle adjusted to suit the individual’s style, the cuff MUST be adjusted to come into alignment with the individual lower leg shape.* This is the final, absolutely necessary step, but it isn’t the correct way to create the initial canting. Any ski boot that doesn’t allow cuff alignment can only ski properly by accident. In the AT world if you only ski in deep powder you may never notice the difference— just never venture onto a groomer on your way back from the sidecountry.
I recently AT mounted a pair of 100 mm waist skis that had been my resort powder skis for several years back in the day. I have 70 + days on them and know exactly how they ski with my normal 2 degrees of cant and alpine boots. I have nothing out of the ordinary in leg and foot structure apart from large calves. Mounted flat with AT bindings and Diabello AT boots with no cuff adjustment they were virtually un-skiable during the first test run on a moderate groomer.
Only by using extreme knee angulation was i able to create any kind of edge engagement .
Lou, maybe you should start a business modding all the ski boots that forgot to include cuff alignment adjustment! LOL
* Lou, funny that you should mention the Atomic FIS race boots. They are notorious for requiring extensive re-working. Even the best ski racers in the world have been known to refuse to ski in a new boot once their tech has created one that works for them.
Purchased Technica Mach 1 (<-silly name) low volume 130 flex alpine boot. The boot fitter played with small wedges under the foot bed, which miraculously changed my leg's engagement with the cuff. Its been a miracle for me. Best skiing boot I've had in 30 years… super solid edge control. For Alpine here in Maine, its 90% hard snow or ice, so edge control is not optional.
Good to hear Jack, I’m still a big advocate of boot fit tuning, though outside of performance groom skiing and alpine racing, the concept has never gained much traction. Lou
Lou, you are absolutely right. “Outside of alpine ski racing bio-dynamic alignment has never gained much traction.” Perhaps that is why you see everyone from members of the US PSIA instructors Demo team to the majority of recreational resort skiers twisting there knees into an A-frame stance trying to achieve edging of the outside ski. Mis-alignment not only limits their ability to cleanly carve a turn, but speeds them on the path to bionic knees when they reach middle age.
How is this relevant to AT skiing? First of all, If you look around you while skiing at any resort you will note that pintech bindings are nearly as common as those abominable snowboards. Or read the comments of people who are excited about the SHIFT binding. They seem to be resort skiers who want to occasionally tour. So the benefits of being in bio-dynamic alignment for them are exactly the same as for an alpine skier.
For the core AT skier who hates fake snow and machine grooming, proper alignment is still important. When you encounter a steep patch of ice, suddenly the ability of your edges to engage becomes important — even the difference between a life threatening fall and maintaining control. As the width of skis that pintech bindings are being asked to control grows by the year. the importance of having the ski canted so it rides neutrally on the snow grows exponentially.
Here is the Bible of Alignment!
https://harbskisystems.com/collections/skier-alignment/products/alignment-technician-course-manual
Yeah, due to my own genetics/biomechanics I’ve battled the A-frame nearly my whole life. Still haunts me, when I get lazy about setting up boots. Lou
The fact that so many boots don’t have adjustable cuff pivots (including the new Maestrales!) is amazing to me. Sad to say, but it fits right in with binding failures and crampon incompatibility.
I used to say that I wouldn’t buy a boot without cuff cant becuz I am knock kneed/flat footed BUT I got the mercury and then Vulcan which have fixed cuff pivots , put a good sole foot bed in there AND … I don’t say that anymore
In my experience, one needs both.
And the cuff can be adjusted on the hill with simple tools.
It may be a quick and dirty adjustment, but how many people really get their boots perfectly fit? In my experience, if you’re not your own bootfitter (which most people are not), good luck getting everything dialed.
I got expert alpine skiing buddies who have taken say a size 26 lange forever and they order on line no problem , even fit the Lange AT boot perfect
So I think its really about finding YOUR brand your model which for me right now is the Vulcan
I am pretty close to a perfect fit, I bought Vulcans cheap from chermany, swapped the liners over from the mercs went touring and did some good vert right out of the box
Fair enough, XXX_er. I’ve got hard-to-fit feet, so there is no such thing (as far as I know) as boots that fit me well right out of the box. But I still don’t think footbeds are going to fix issues related to lower legs that angle in or out.
tell me about it
I got small feet so right away > half the boots made don’t fit, are too soft, too narrow and come in an unmanly colors
I found the Mercury/Vulcan totally by accident so now I’m a fanboy,
IMO there is a boot out there that fits you … but you haven’t found it yet
same with foot beds, find your match, so IME an off the rack Sole foot bed solves my flat foot/ collapsed arch/overpronation/ need for cuff cant … even > my custom made
See, I hear you about being your own boot fitter, but unfortunately it’s not really a one person process. There needs to be somebody positioned in front of the skier during initial bench work to evaluate the results of canting and alignment as the skier flexes and assumes positions that mimic skiing. And because skiing is a dynamic activity, the alignment process is not complete until the results are tested and verified on snow. Video in slow motion is by far the best tool.
It’s easy to understand why boot fitting usually stops at making them so they don’t hurt. Far easier to sell a new pair of boots with color matching graphics or a new pair of skis than a process that requires time and skill.
Two resources for canting AT boots that don’t allow boot sole grinding or tread replacement:
1- Gorilla tape: Extra tough and thick duct tape– On all alpine bindings and frame style AT bindings it is handy to build up one side of the heel strike region to achieve temporary canting and arrive at a measurement for the wedge that will go under the bindings.
2- Canting wedges: hard to find— here is a source: http://www.tognar.com/ski-binding-cant-strip/
along with hundreds of other waxes and widgets.
Provided you don’t have super thick tibia and calf muscle, just get the footbed made first, then shim the liner cuff with layers of dense foam glued to outside to align with leg. Not quite a good as tilting “canting” the boot cuff, but works, that’s how I often do it. I like wedges under the bindings as well, but had to give up on that years ago, so many bindings, so little time (smile). Lou
As Crazy H. said a few days ago, “Any ski boot that doesn’t allow cuff alignment can only ski properly by accident.” I would like to take that a little further and say that, with adjustable cuff pivots, getting an acceptable cant adjustment can be as easy as putting the little tool that came with the boots in your pocket, taking a few runs at the resort and adjusting the cuffs until they feel about right. No slow motion video or foam shimming required. That’s why I find it so ludicrous that so many boots lack this feature.
(Once you get the cant dialed, apply threadlocker and you’re good to go.)
Hi Lou and Crazy Horse,
Just want to put a word in for the concept and practice of using no foot beds and a boot board that is flat both ways (no arch form) and reducing the boot board ramp angle to no more than 2.8 degrees. When combined with proper cuff flex and full toe/metatarsal splay the results for me, were nothing less than astounding. Before I had a total ramp angle of 9+ degrees (5 in my TLT5 and 3+ from the Dyna Speed Radical, and 1 from the difference toe-heel in the tech binding boot insert , A-Line footbeds, Intuition Pro Tour, and required 3 and 4 degrees of cant under the bindings to ski well. Now I am at 2.5 degrees of boot board ramp and zero delta on the bindings and no cants under the bindings. I removed all the padding on one side of the standard type liner I now use including the medial side of the cuff to give me room for proper foot movement and flex and, yes, dare I say it PRONATION (i.e. natural foot function like most of us were born with!
It is now ridiculously easy to balance when skiing. I was very fearful of falling on my face or butt but, it just didn’t happen. No backseat, no face plant! I am still tweaking my set up and doing all the work myself as I can’t find anyone who thinks it can work. Even my bootfitter of 20 or so years said it could not be done, that ramp angle inside the boot was a non issue, and footbeds were necessary. I have proven them wrong and more importantly found the answer to most if not all of my skiing difficulties. The need for heel wedges (had them too) footbeds, ( I had at least 7 custom beds), and the aforementioned binding cants, and radical locked in forward lean – it all went away! My feet are much more comfortable and don’t ache after skiing and without the pressure of “perfect envelopment” have a lot more circulation.
Shocking, unbelievable, mind blowing, etc., etc. My first few attempts at this were not very successful, until I figured out all the impediments to achieving the 2.5 degree ramp angle which is not set in stone but, still being explored (downward). I was converted to barefooting about 8 years ago and my feet would ache for a week after skiing in my old set up so I looked and found The Skiers Manifesto (website skimoves,me) by David MacPhail. For much more real information on this concept and more check it out. Oh, and don’t dis it until you can PROVE that it doesn’t work! I have seen disparaging remarks on Harb’s website about the Manifesto and it really is disappointing of Harald to take that attitude. I am a Harb system believer, I even have a pair of Harb footbeds, and much of David’s work agrees with his system. I have not read any disparaging remarks about other individuals on that website (skimoves.me). David backs up what he says with real world research and data and has generously provided us with an incredible amount of knowledge.
I started skiing about 1959-60 and this is the best thing I have found in skiing so far! It has renewed my enthusiasm which was not lacking at all and is a real boost at my age (69) since it makes skiing so much easier and less tiring. Now, if I can find a way to make skinning this easy I could be backcountry skiing into my 90’s!!
Don’t knock it if you haven’t actually tried it. No half measures will work- been there, done that, so don’t waste your efforts. If you do it right you will be rewarded.
Lou, I don’t know if this will work with your frozen ankle but, who knows. As David says, some people may find that they need to support the foot, especially if you have a deformity or traumatic injury so its not like you can’t get there if you need footbeds or other accommodations.
Best regards,
Herb
Hello Herb, that’s super interesting, I love it. I think there is indeed a tendency to try and do what alpine racers do to shave hundredths of a second off their times, when there may be entire other methods of boot fitting. I know in our case and in a trend I’m seeing, the often excessively narrow metatarsal area in most boots (feel that 95 mm last!) is getting punched, and punched, and punched. Nearly everyone I see with one of the narrower touring boots has punch bumps in the mets area. We’ve been punching ours out like crazy, enabling these really wide metatarsal areas to prevent neuromas and just generally be more healthy for our feet. It’s really pretty funny to watch these trends, but I do take them seriously and feel that everyone should think a bit outside the box when configuring their ski boots. Lou
What’s next, softer shells?
@ See
Why not ?! Leather boots come back!
I’m all for it (well, maybe not leather). I like softer boots (up to a point) for most situations. I feel like they’re better for climbing and easier on the body. Even though I use soft boots I can’t recall wishing for anything stiffer, even on big skis.
Comments are closed.