Chord Center mounting- does it make any sense?

[phoenix]

Fisheater made a very valid observation above, at least in my opinion, and experience. Which is the foundation for the "ball of foot on center of running surface" school of thought on mounting that started earlier this century. In today's world that center of running surface would correlate to the mid-boot mark. More or less.

Most valid summary is still "it depends".

[lilcliffy]

Fisheater's BP for his FT62's was pretty much on CC.

GARETH-- do you remember where yours fell on the FT62?

Specs on my 2018-2019 FT62 (I was prepping them today with fresh snow coming tonight!)- measurements are from tail:

- Length:188cm (difficult to measure precisely because of tip and tail rocker- but they are all of 188cm)
- Balance Point (BP): 93cm
- Chord Length (CL): 186cm
- Chord Center (CC): 93cm
- Running Surface (RS)/effective edge: 124cm (length of effective edge)

The FT62 does not have a parabolic sidecut (just like my Storetind and my Kom). The narrowest point of sidecut (NPS) of the FT62 (62mm wide) is extented for a a considerable distance.

With my binding mounted at BP- my ball-of-foot (BOF) falls precisely on the center of the running surface (CRS). This is a brilliant design.

I have been thinking about this quite a bit today...
The NPS on the FT62 and the ST are fairly long- accommodating feet that are both shorter and longer than my size 42EU.

SO- with the binding mounted at BP the ski will feel completely balanced with a Nordic binding and anywhere that ski is pressured will be at the NPS.

All of this combined with significant tip rocker results in a ski that feels perfectly balanced yet has a mounting that is "forward" on the effective edge of the ski.

This is some really cool stuff...

It leads me to my current conclusion that I would mount a Nordic binding on any ski with this sort of design at BP- regardless of the size of one's foot.
(I wonder what the difference is between NN and NNNBC in this context...NNN is mounted on the bar- mounting NNN vs NN results in a more forward mounting point...)

I need to measure my Kom and see where Altai's recommended mounting point is compared to the ski's BP...
Altai Skis recommend mounting "pins" at a specific point- regardless of boot length.
The Koms also do not have a parabolic sidecut- they have "early" taper- with a long NPS section- just like the FT62 and ST...
The Koms were definitely designed for Nordic/Telemark bindings- NN specifically...

[Woodserson]

The FT, Rabb, Tindan, all brilliant. I also noticed the very long section of narrowest point of sidecut. I applied the calipers to the skis and they all exhibit this trait. Tres cool.

How are you calculating/measuring Center of Running Surface? Contact points on an uncompressed ski against a flat surface, or compressed with camber flat and rocker in action?

[lilcliffy]

I am measuring the running surface/effective edge with the camber compressed- excluding both tip and tail rocker.

[wrussl]

I agree with fisheater. Traditional and true telemark technique involves the skier being on the balls of feet for both skis with each ski weighted equally and both skis working as one.Granted the rear ski heel will be lifted much higher. A tip I got while learning during the leather age was "big toe, little toe". Think of pressuring the big toe on the downhill ski and little toe on the up hill ski. With traditional camber skis I don't think boot sole mid line to ski mid line, as marked on the ski, makes sense because the weighted or pressured part of the ski is always forward over the ball of the foot in telemark vs middle of the foot in alpine. So the binding should be mounted a bit to the rear to compensate so that where the boot pressure actually is (around the bellows) is over the narrowest part of the ski. As fisheater says, it is not possible in telemark to leverage the front of the ski by flexing the shins into the boot. Telemark is about balance between skis and using knee, hip, and ankle rotation to turn. If one is skiing with such active bindings and stiff boots to be able to drive a ski by flexing the shins, then is it really telemark anymore?

[joeatomictoad]

Telemark is about balance between skis and using knee, hip, and ankle rotation to turn. If one is skiing with such active bindings and stiff boots to be able to drive a ski by flexing the shins, then is it really telemark anymore?

One drill I use; to improve balance, to not "drive forward" so much, and not bend the rear leg so much; is to envision an imaginary ball of energy between the front/rear boots in the middle of the turn. The "energy ball" increases energy with imaginary "compression". So I try to compress the energy ball by "squeezing" the front/rear boots together in a tele turn.

Maybe this drill is reinforcing good techniques; maybe bad techniques. I am not a pro here. Nevertheless, when I do this drill, I do not drive the turn so much with my shins, my balance is better, I don't feel the need to drag knee as much, and my center of gravity feels better positioned.

[lowangle al]

I agree with fisheater. Traditional and true telemark technique involves the skier being on the balls of feet for both skis with each ski weighted equally and both skis working as one.Granted the rear ski heel will be lifted much higher. A tip I got while learning during the leather age was "big toe, little toe". Think of pressuring the big toe on the downhill ski and little toe on the up hill ski. With traditional camber skis I don't think boot sole mid line to ski mid line, as marked on the ski, makes sense because the weighted or pressured part of the ski is always forward over the ball of the foot in telemark vs middle of the foot in alpine. So the binding should be mounted a bit to the rear to compensate so that where the boot pressure actually is (around the bellows) is over the narrowest part of the ski. As fisheater says, it is not possible in telemark to leverage the front of the ski by flexing the shins into the boot. Telemark is about balance between skis and using knee, hip, and ankle rotation to turn. If one is skiing with such active bindings and stiff boots to be able to drive a ski by flexing the shins, then is it really telemark anymore?

Hey russi, welcome to forum. I have to disagree that you weight the balls of both of your feet. On my downhill ski I pressure my whole foot equally which puts the weight over boot center. There are times when I'll weight the lead ski towards the ball and times when I weight it towards the heel but in general it's a flat foot.

On the trailing ski the weight is only on the ball of your foot which puts it ahead of the boot center of the ski. Since the rear ski is the harder one to control I think you have an advantage with it being closer to the tip.

Big toe, little toe is a great way to think about pressuring your skis, but on the lead ski I pressure it on the big toe side but evenly distribute the weight on my whole foot. You will get more control with approximately 30cm of length pressuring the ski that you will only using half of your boot. Give it a try to see if you feel a difference. I think it will also help you get centered better.

[wrussl]

@joeatomictoad: I think I understand your "ball of energy" idea. Makes sense. Sounds similar to the "imaginary ball between the knees" drill. The idea being that you imagine you have a ball between your knees that you don't want to loose. The knees rotate around the ball during lead changes, but never get far enough apart (front to back or side to side) to loose the ball. Helps improve quick transitions and keeping balanced and centered over the skis and avoiding doing the splits with one ski way out in front of the other.

[wrussl]

It's all good

[lowangle al]

Not being centered with a 50/50 balance isn't my problem, in fact I don't have any problems. I didn't come up with the idea about keeping the lead ski flat on my own. I got it from one of Dickie Halls later instructional videos, and it works.

If I'm in deep powder and want my skis to come up I may put more weight on my heel. If I'm on steep hard packed slope where controlling my speed is my priority I will weight the lead ski more towards the toe to get more edge contact earlier in the turn. Other than that it's a flat foot, and I don't really see how that affects my for aft balance.