How Much Does Metal Mounting Plate Matter?

[BigJohnS]

Lots of people talk about having metal in the mounting area of ski used for downhill telemark to prevent binding pullout but XCD skis don't have metal and people don't seem to have a problem with it. Is this more due to the fact that XCD skis aren't skied as hard or is it because more neutral bindings are used? Binding pullout is discussed more with telemark bindings than alpine bindings so what makes a telemark binding more likely to pull out?

[jtb]

It's because XCD skis normally aren't skied as hard, are often paired with softer boots and bindings, and are less likely to be used on hard pack or groomed snow.

Telemark bindings pull out more than alpine because you have a long lever (the foot) connected to two narrowly spaced points with opposing forces (the toe and pivot). It's basically the same principle as using a crowbar to pull out a nail. If you have the same bar connected to two nails at either end and pull up from the middle, it's not nearly as easy to pull one of the nails out. Also if you have soft boots and springs, the equivalent of a floppy crowbar, it's harder to pull out. Also keep in mind that a day of resort skiing puts 10-20x as many duty cycles on the ski as a backcountry tour, and each cycle has more force applied if skiing hard pack.

Anecdotally, I have snapped two paulownia skis that did not have a plate in the mounting area. I have never snapped a ski made of stronger wood or one with a plate. However, I also have two pairs of paulownia skis with no plate (Voile Objectives) that I've skied as hard as any other ski and not split the core or pulled a binding. I think the quality of the wood and other elements of the layup matter. I mount all of my skis with inserts for maximum retention, but sometimes this just causes the core to delaminate before the binding screws can pull out.

[CIMA]

The height of boots and the styles of telemark skiing affect the damage, too. The clawbar effect as @jtb said.

[BigJohnS]

Ok, so if I understand what you are saying then what I was thinking is correct, of course more force from skiing harder on downhills will increase the chance but the increase of risk over alpine is due to the pulling force resulting from lifting the heel. So I would think a more active binding like a freeride would be more likely to pull out than a targa.

The reason I am wondering about this is because as I mentioned in another thread I'm looking to mount some targas on a pair of alpine skis to use at the resort. I don't really want to spend a lot of money on it right now so I was thinking about maybe mounting them to a pair of Volkl Bash 86s I got from someone but never mounted because I don't ski park. I know they wouldn't be ideal for what I want them for but it's what I have. I'm pretty sure they don't have any metal and looking around online I read that they have a beech and poplar core. I also read on another website that they have denser wood around the binding area and lighter wood near the tips and tails so I assume the mounting area is beech. I also read about people having quality issues with the Volkls made in China but these say made in Germany on them so I would think they are of higher quality.

[CIMA]

When skiing with a normal telemark setup, I never considered the metal mounting plate. My telemark friends have never mentioned it either. I've heard that some skiers bring spare wires for 75mm cable bindings during their ski tours, but I always thought that the spare wires were unnecessary for me. Unless your skiing style resembles that of a Cossack dancer, it's unlikely that you'll encounter any issues.

[wabene]

[fisheater]

@BigJohnS Stiffer springs, and especially a spring that bottoms out at the end of travel, offer a greater prying action.
If you have a ski, and like the flex, I would mount it and ski it.