DIY Tech Binding Heel Spacers

[Sklimber]

Ever since I skied Plum guides with the heel spacers vs without I realized their usefulness in helping with the downhill, especially in variable or crappy snow conditions. Unfortunately not a lot of tech bindings come with that option. Let's see your DIY heel spacers.

Mine are in the early stages. I cut some binding freedom inserts in half, drilled and tapped into Trab Vario heels (before mounting) and tapped/drilled/epoxied the inserts into the heel pieces. I’ll be able to add or remove a piece of plastic with a M5 screw that will serve as a heel spacer.
Top view


Bottom view post epoxy.

[GoldenBC]

I cut the AFD and rear two screws off an old fks 12 and they fit perfectly with my MTN with toes on a 4mm shim and no heel track.

[Sklimber]

I cut the AFD and rear two screws off an old fks 12 and they fit perfectly with my MTN with toes on a 4mm shim and no heel track.

Have pics?

[GoldenBC]

[Sklimber]

End result for the Trabs. I put the M5 screw into the hdpe plastic spacers. Can screw and unscrew by hand if the approaches are flat for a while. Hopefully they hold up.

[Sklimber]

Does your boot heel rest on the spacer or is there a slight gap?

[Sklimber]

The other experiment with some Plum guides. The ramp angle on these is high so the spacer is quite substantial. I drilled a quiver killer under the heel, put the m5 screw into a round piece of plastic and can screw and unscrew by hand. A 1.25" fender washer under the plastic helps it snug down nicely.

[frorider]

Freeride spacers have been a project of mine last couple of years. I have the ATK integrated spacers on my Raiders, and I bought the Universal ATK sliding spacer last year since I heard they were discontinued.

For anyone with a boot quiver the spacers are a pain in the ass, since net heel thickness varies so widely among boots. My 107 mm skis get used with my Skorpius II and Zero G TP boots so I’ll be leaving the heel spacer height optimized for the ZGTP and just live with the 4 mm gap that makes em useless with the Skorps.

In practice the heel spacer needs to be about the width of the boot sole or it really doesn’t improve edging power / torsional support enough to be worth it.

If you raid an old binding bin at a shop, the Salomon Warden sliding AFD unit is small and light (28 g), as light as the ATK universal. But you’ll need a thin plastic shim under it to get to right height.

The ATK universal does not adjust down low enough to work with low delta bindings like the Marker Alpinist, so a DIY solution is essential.

For a high delta bindings (which I avoid anyway), a heel spacer will suck for skinning flats. But on a binding like the Alpinist I find it’s barely noticeable on flat approaches.

Personally with the compromised release characteristics of tech bindings, I’m focusing on sliding AFD heel spacers that mimic the ATK integrated spacer performance.

[GoldenBC]

Does your boot heel rest on the spacer or is there a slight gap?

It rests on it under my body weight

[AlpiNord]

Freeride spacers have been a project of mine last couple of years. I have the ATK integrated spacers on my Raiders, and I bought the Universal ATK sliding spacer last year since I heard they were discontinued.

For anyone with a boot quiver the spacers are a pain in the ass, since net heel thickness varies so widely among boots. My 107 mm skis get used with my Skorpius II and Zero G TP boots so I’ll be leaving the heel spacer height optimized for the ZGTP and just live with the 4 mm gap that makes em useless with the Skorps.

In practice the heel spacer needs to be about the width of the boot sole or it really doesn’t improve edging power / torsional support enough to be worth it.

If you raid an old binding bin at a shop, the Salomon Warden sliding AFD unit is small and light (28 g), as light as the ATK universal. But you’ll need a thin plastic shim under it to get to right height.

The ATK universal does not adjust down low enough to work with low delta bindings like the Marker Alpinist, so a DIY solution is essential.

For a high delta bindings (which I avoid anyway), a heel spacer will suck for skinning flats. But on a binding like the Alpinist I find it’s barely noticeable on flat approaches.

Personally with the compromised release characteristics of tech bindings, I’m focusing on sliding AFD heel spacers that mimic the ATK integrated spacer performance.

Good insights. When I started going down this rabbit hole, the sliding/elastic AFD approach added next level complexity. Adjustable height seems attainable. I can think of a couple ways to get some limited sliding action but it could be a PITA to get it right. How much lateral sliding is needed?

What about a simple round over shape/bar with minimal contact across the boot heel width?

(Edit) Conceptually:


(2) Inserts & (2) M5 low head SS machine screws

[frorider]

^ the notched 2 piece ATK Universal spacer uses that same basic design to adjust height. The integrated ATK raider spacers use shims, which is fine but then when you’re using different boots you have to locate your ATK box with the shim quiver .

[AlpiNord]

^ the notched 2 piece ATK Universal spacer uses that same basic design to adjust height. The integrated ATK raider spacers use shims, which is fine but then when you’re using different boots you have to locate your ATK box with the shim quiver .

To avoid the shims and for universal fit for other bindings as well, what adjustment min & max range would be useful? Currently printing an initial 'draft'. I'm thinking a width of 70mm or so would provide good support.

[Cocximus]

I don't want to pull the shifts off my skis but the afd on them look like a beefy option that could be adapted.

Sklimbr pics with the trab make me reconsider if I want a spacer. It looks like they end up adding quite a bit of height and I like flat even on steeps.

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[GoldenBC]

Funny, when I had shifts I was going to pull the AFD and retrofit a solid non adjustable one onto the ski. Fuck the shift AFD.

Remounted my pivot AFD onto a new ski. Used a duct tape gasket under the piece and it got rid of the audible click when climbing.

There are lots of sliding AFDs you could cut off an existing binding and grind to fit.

[redbarnPD]

There was an instrumented study out there years ago that tested "new" sliding AFD's up against the original PTFE fixed units on alpine toes (rough equivalent of tech heels). I can't seem to find that study, but the bottom line was that the fixed PTFE/Teflon presented less friction under load (lateral releases are almost always under spiked loads).

Having tested several alpine & tech binding with an old Vermont tested (twisting torque to release) with and without load, I am guessing that unless a sliding AFD is suspended on bearings, or some other relatively frictionless assembly, the best release performance will be with good 'ol PTFE/Teflon. I'd guess most alpine binding makers switched to sliding AFD's for marketing and cost reasons, since the old fixed AFD's were 2mm+ thick PTFE and that stuff is expensive!

I tested this with said Vermont tester and was happy with the results:

https://www.tetongravity.com/forums/...=alpinist+heel

[fleaches]

Drop in spacer for the Alpinist, fits in the slot where the little stomp pad goes

V1 isn't adjustable, I just printed to the height I need. Thinking about an adjustable version in the future if this works OK.


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[frorider]

Cool, looks clean. My tecnicas need a 14 mm spacer for the Alpinist. skorpius needs a bit over 15 mm.

[cat in january]

There was an instrumented study out there years ago that tested "new" sliding AFD's up against the original PTFE fixed units on alpine toes (rough equivalent of tech heels). I can't seem to find that study, but the bottom line was that the fixed PTFE/Teflon presented less friction under load (lateral releases are almost always under spiked loads).

Having tested several alpine & tech binding with an old Vermont tested (twisting torque to release) with and without load, I am guessing that unless a sliding AFD is suspended on bearings, or some other relatively frictionless assembly, the best release performance will be with good 'ol PTFE/Teflon. I'd guess most alpine binding makers switched to sliding AFD's for marketing and cost reasons, since the old fixed AFD's were 2mm+ thick PTFE and that stuff is expensive!

I tested this with said Vermont tester and was happy with the results:

https://www.tetongravity.com/forums/...=alpinist+heel

I remember those test results. It was a while ago and I wonder if it was a solid boot sole or if gripwalk boots were tested. Would the luged soles of touring boots favor the non sliding as well?

[Cocximus]

I remember those test results. It was a while ago and I wonder if it was a solid boot sole or if gripwalk boots were tested. Would the luged soles of touring boots favor the non sliding as well?

This. I am pretty sure that test was on regular alpine boots.

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[coldfeet]

I am pretty sure that this is Jeff Campbell's work on boot release, that he tested alpine and AT lugged sole boots, and that the significant difference was for lugged sole AT boots (I think both typs of AFDs worked as intended for alpine boots). This was in 2016/17 or so and likely before GW/WTR boots fully took over. I can't find the original link to the paper, but here is a link to the PubMed abstract - unfortunately you have to subscribe to read the full text. https://pubmed.ncbi.nlm.nih.gov/28513243/

Here is a Ski Mag article with quotes from Campbell about how a problem is sliding AFDs combined with lugged soles: https://www.skimag.com/gear/ski-boot...bility-issues/

[redbarnPD]

Very nice, bravo!

You will probably still want some PTFE glued on top of the 3D print, but that should be pretty easy with most of the "nylon-like" print resins and some cyanoacrylate. Did you go with 0.5mm to your boot sole?

Would be nice to come up with a quickly height-adjustable design, but that woudl take time away from skiing. My ghetto brake stomp version is still holding strong and skis nice. Report back when you've skied it a bunch!

Drop in spacer for the Alpinist, fits in the slot where the little stomp pad goes

V1 isn't adjustable, I just printed to the height I need. Thinking about an adjustable version in the future if this works OK.


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[redbarnPD]

Yep, that's the study, nice find. Definitely done with alpine soles, not Gripwalk.

As the Campbell study showed, predictably, lugged rubber touring soles make things worse (so does dirt). It's very much a boot+binding system deal, they need to be adjusted & calibrated together. I got lucky with my PTFE stomps since my light & beef boots are almost identical sole thickness, but most won't be that lucky.

I'm pretty convinced that a height adjustable PTFE stomp (no lateral sliding mechanism) is the way to go. Basically, just trade the complicated lateral sliding mechanism for a slightly less complicated screw-ramp height mechanism. Then you could adjust the AFD correctly for each boot with a cheap slidey gauge.

Oh wait, I just described an alpine GW toe... Anyone fluent in Italian and feel like talking to the ATK guys?

I am pretty sure that this is Jeff Campbell's work on boot release, that he tested alpine and AT lugged sole boots, and that the significant difference was for lugged sole AT boots (I think both typs of AFDs worked as intended for alpine boots). This was in 2016/17 or so and likely before GW/WTR boots fully took over. I can't find the original link to the paper, but here is a link to the PubMed abstract - unfortunately you have to subscribe to read the full text. https://pubmed.ncbi.nlm.nih.gov/28513243/

Here is a Ski Mag article with quotes from Campbell about how a problem is sliding AFDs combined with lugged soles: https://www.skimag.com/gear/ski-boot...bility-issues/

[fleaches]

Very nice, bravo!

You will probably still want some PTFE glued on top of the 3D print, but that should be pretty easy with most of the "nylon-like" print resins and some cyanoacrylate. Did you go with 0.5mm to your boot sole?

Would be nice to come up with a quickly height-adjustable design, but that woudl take time away from skiing. My ghetto brake stomp version is still holding strong and skis nice. Report back when you've skied it a bunch!

The white on top is PTFE. The most expensive part of this project was getting some primer and glue for that.

Yeah it's somewhere between 0.5 mm gap and "just touching". This one is for some skorpius boots so like frorider said just a bit over 15 mm.

I guess another way to go here would be to make a system where there's a receiver that's mounted to the ski and a pad that goes on top that can be swapped out with different heights. Maybe you'd have two different height pads for different boots instead of a fully adjustable universal one.

[AlpiNord]

The white on top is PTFE. The most expensive part of this project was getting some primer and glue for that.

Yeah it's somewhere between 0.5 mm gap and "just touching". This one is for some skorpius boots so like frorider said just a bit over 15 mm.

I guess another way to go here would be to make a system where there's a receiver that's mounted to the ski and a pad that goes on top that can be swapped out with different heights. Maybe you'd have two different height pads for different boots instead of a fully adjustable universal one.

Rather than glue, is it possible to countersink the PTFE piece for flat head screws? And/or instead of a flat piece could it be a 1/2" or so PTFE rod?

[redbarnPD]

For sure, PTFE block or rod machine easily.

But the cyanoacrylate bonding (not gluing) works amazingly well. Since virgin PTFE chunks are rather pricey, this is how the binding biz has been handling it forever. PTFE sheet is readily available in a bunch of different thickness' and the model-making community (RC folks) are your friends for bonding different plastics permanently.

I've got 6-7 tours, 1000's of bad stomps, dirt, pebbles, weeds and general mishandling on a home-bonded stomp with 1mm PFTE bonded sheet and it is bomber. Scratched to hell, yes, delaminated, no.

Rather than glue, is it possible to countersink the PTFE piece for flat head screws? And/or instead of a flat piece could it be a 1/2" or so PTFE rod?