SKI PRO MATT: NEUTRAL START BOOT SET UP


By the time Matt arrived in Whistler on November 5th last year, we had explored a number options for ski boots. Matt was skiing in Fischer. But we agreed it was better to start clean. The choice came down to either a Head Raptor 130 or an Atomic Redster 130.  Matt elected to go with Head. I considered this a starting point because I normally go with the stiffest shell available. I will explain why in a future post.

My opening move was to try and achieve a neutral set up in terms of creating a functional environment for Matt’s foot. His foot could not function in his current boots. So he had to adapt his technique to the boot. The objective was to adapt the boot to Matt. The process started with a shell check to confirm whether the shell was sized correctly in terms of interior length for the foot. It was tight. But not so tight as to require going to a bigger shell.

Next I checked the ramp angle of the boot board or zeppa that sits in the bottom of the shell. I discussed this issue in my post, WHAT’S YOUR ANGLE? ( https://skimoves.me/2014/03/29/ski-boots-whats-your-angle/ ‎). Although digital instruments are available to measure boot board angles, I prefer to calculate the angle using an online software such as the one on Cleave Books UK (http://www.cleavebooks.co.uk/scol/calrtri.htm) and treat the boot board as a right angle triangle. The graphic below is a screen shot of the Cleave Books UK calculator. If you enter any 2 fields it will calculate the remaining fields. I use edge b and angle A to calculate the toe/heel height difference to give me the desired boot board ramp angle, usually 2.7 degrees. Then I mark the heel of the boot board and grind it down to the mark.

Cleave Books

I measure the length of the base of boot board and insert the number in edge b field. In the example shown in the Cleave Books calculator, I used 280 mm. Then I plugged the desired boot board ramp angle into the angle A field and hit [ Calculate ]. The height difference between the toe end and heel end of the boot board needs to be 13.2 mm.

Here is what edge a and angle A look like superimposed on the photo below of a Lange a boot board. The ramp angle is 4 degrees, over a degree too much.

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Before Matt even put his foot in the shell, I could easily see the areas where there would his foot would need clearance. I outlined the area in red in the left photo below. It was a given that there would be clearance issues with width of Matt’s forefoot and the alignment of his big toes. It is critical that the big toe is able to assume its natural alignment in the shell. To fine tune a shell fit, I like to use toothpaste or some sort of thick cream to coat the suspect area. The foot is carefully inserted in the shell and then weight applied by the skier. The right photo below shows the area where the toothpaste would be applied to Matt’s foot. A quick shell confirmed my suspicions. The marked area was hard against the inner wall of the boot shell. We were a long way from fine tuning.

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The next step was to pay a visit to local boot-fitter George McConkey. George works at McCoo’s in Whistler Village.

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George confirmed my assessment and got to work.

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The photo below shows how much the shell had to be expanded for Matt’s big toe. Next George worked on the area around and below the inside ankle.

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With Matt in good hands, I left him with George for what was going to a long day.

In my next post I will cover the liner modifications made to Matt’s boots.

 

 

4 comments

  1. I have been following your posts for 2 years now and find them extremly helpful. Role of pronation in edging as well as slow mo videos of Ligety were revolutionary to me! However, some things are not clear to me. For example, how do you mitigate the fact that by reducing the ramp angle of the zeppa and leaving the forward lean the same you functionally close the ankle? For skiers with average or fuller/lower calf muscle it would tesult in difficaty to extend

    1. What do you mean by ‘functional close the ankle’? Perhaps the issue may become clear when I discuss Resistive Shank Angle, Ankle Flexion vs Boot Shell Flexion (i.e. deformation), Shank Free Play within the Boot Shaft and Arch Dynamics and Intrinsic Tension.

      The shaft of the boot must be configured so as to address these issues. The shaft of my wife boots has had the forward lean dramatically reduced, the side cant altered so it is inward more than the stock adjustment allowed. The issue is not extending the ankle as in plantarflexing it. The issue is allowing a skier with a fuller or lower calf muscle mass to assume the Resistive Shank Angle. This is a huge problem that is making it difficult for a lot of women to ski. I will post some photos of my wife’s boots to show the modifications I made.

      After I post on these issues, please get back to me if they are still not clear.

  2. Dear David,
    What is your guidance re appropriate sizing of the shell?
    Following your blog with great interest.

    1. Mike, the answer depends on how badly you want to ski and to what lengths you are prepared to go. As a general rule, I choose the stiffest shell a skier/racer can get their foot in because over-tightening the closures usually significantly distorts the shell and makes the effects of loading unpredictable. But making the smallest and stiffest boots work can take some pretty drastic measures. I am about to post on what I did to Matt’s liners. This should answer your question. If not, please get back to me.

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