Pin vs alpine binding delta comparison

[waxoff]

Pin binding delta has been referenced in a few threads where numbers are given for pin height heel to toe difference. I find this misleading as those numbers should not be compared straight away to the classic way of describing the heel to toe stand height delta.

I commented on this recently in another thread but thought this topic might deserve its own thread. So I here it goes.

I was about to shim my Radical toes and wanted to be somewhat scientific about it (when calculating desired shim thickness) by comparing the actual binding delta beteween the Radical's (which I find steep) and non shimmed Sth2's (Which I almost like as is but shim toes 2 mm for perfect feel). With boot in the both bindings I measured vertical with caliper from topsheet to green dots on welts. Adding pics for reference.

The results shocked me as the delta was within a couple of millimeters between the two bindings.

Nb, I don't ski with Cosmos in Sth2, I only did this for delta comparison.

Still, skiing in the Dynas with Cosmos toes unshimmed feel like high heels. So I put an alpine boot on one foot and Cosmos on the other, and step both into Sth2. And I got the familiar high ramp delta sensation in the Cosmos leg. So the boot had a much higher impact of the ramp delta sensation than did the bindings. All in all, the Sth2 gets a 2mm shim and the radicals get a 6 mm shim for a close to equal feel of ramp delta between the two setups.

Usually I measure binding delta from topsheet to top of afd or the block which the sole rests on. For ease of measuring exactly, and since I was not after a stand height number but rather a comparative number between the two different bindings I opted for measuring to top of welt.

[Spyderjon]

Your measuring system is flawed.

If you stand a boot on a flat surface then that boot has zero delta as the underside of the toe and heel soles are on the same horizontal plane.

Binding delta is the measurement of how high the underside of the sole of the heel is compared to the underside of the toe is - as measured from the horizontal plane - so the relative heights of the top of the welts (where your dots are located) is immaterial & misleading.

So your original measurement method of measuring from the ski base to the underside of the toe & heel soles was correct.

[waxoff]

Your measuring system is flawed.

If you stand a boot on a flat surface then that boot has zero delta as the underside of the toe and heel soles are on the same horizontal plane.

Binding delta is the measurement of how high the lowest point underside of the sole of the heel is compared to the underside of the lowest point toe is - as measured from the horizontal plane - so the relative heights of the top of the welts (where your dots are located) is immaterial & misleading.

I fully agree with you there if I was looking for an absolute number for the delta or stand height. However, my goal was to compare the boot sole inclination when in the two different bindings, which I still believe I managed to do.

Edit, regarding "If you stand a boot on a flat surface then that boot has zero delta..." I would argue that the table, rather than the boot, has zero delta since it is horizontal.

[Spyderjon]

.......regarding "If you stand a boot on a flat surface then that boot has zero delta..." I would argue that the table, rather than the boot, has zero delta since it is horizontal.

The boot has to have zero delta when it's sitting on a flat surface as delta is the relative heights of the toe/heel soles off the horizontal. If you stand in the boot on a horizontal surface you will feel slighty heel high but that is due to the internal forward angle of boot board (zeppa) and the forward lean of the cuff, which are two totally different things than delta.

[waxoff]

I tried to keep zeppa and forward lean out of the picture but since I brought up standing in alpine binders with different boots I guess I had it coming!

Alpine binding delta can be measured without including a boot in the equation. What I'm getting at in this thread is that it is apples and oranges when comparing heel and toe pin height difference on tech bindings to delta on alpine bindings. The part of me measuring on radicals and sth2's was included to illustrate another way of comparing two different set of bindings relative each other.

Therefore I also stated that normally, I would calculate (alpine) binding delta by heel support height minus toe support height. That can't be done on tech bindings lacking sole support, hence (delta, or resulting boot sole inclination) comparisons to other binding types besides other pin bindings can't be made given only pin height difference numbers.

[rod9301]

Why don't you measure the tibia angle with the but in alpine vs tech bindings?

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