Why are Touring Boot Soles so Soft?

[patagonialuke]

After chewing through a few of the rubber soles on my touring boots while scrambling around in the alpine, I continue to wonder why companies put such soft rubber on their boots. While my ski boots' soles are torn apart, the soles on my mountaineering boots (scarpa phantom guides) are doing just fine, and provide plenty of grip.

So, why don't we see more companies putting harder rubber, similar to a hiking or mountaineering sole, on touring boots? I assume it has something to do with the rubber's compatibility with the plastic of the boot shell?

 

[onenerdykid]

What boots are you having issues with?

We partnered with Skywalk and use their best compound for grip and long life. Obviously, favoring one too much over the other will cause the other to suffer, but the compound we use can take a beating and still offer a lot of grip.

 

[patagonialuke]

What boots are you having issues with?

We partnered with Skywalk and use their best compound for grip and long life. Obviously, favoring one too much over the other will cause the other to suffer, but the compound we use can take a beating and still offer a lot of grip.

I had issues with the Dynafit Mercury and Fischer TransAlp.

I forgot to take a closer look at the rubber on the Backland and XTD at SIA, but I'd be interested to try them out to compare, especially with the XTD's integrated WTR pieces.

I just don't understand why companies (Fischer and Dynafit in my experience) use such a soft rubber. It is substantially softer than any of my hiking/mountaineering soles. It's not like I'm trying to climb 5.12 in my ski boots, and it seems like durability on non-replaceable soles is a common issue with consumers. I guess I can see the merit of an ultra-grippy sole for boots like the TLT's, Backland, Travers, etc. as they'd be more suited for more technical ski mountaineering, but putting a sole like that on a free-touring boot like the Mercury or Transalp seems like overkill and inappropriate. I'd be stoked to see something like a Vibram Mont sole on a ski boot.

On the manufacturing side - are there limitations as far as what kinds of rubber are compatible with the various plastics of ski boot shells?

 

[onenerdykid]

On the manufacturing side - are there limitations as far as what kinds of rubber are compatible with the various plastics of ski boot shells?

It's more of what plastics don't stick to rubber. Each plastic (polyurethane, polyamide, polypropylene, etc.) requires an über specific glue and primer to get anything (including rubber) to stick to it. But every brand should have that figured out by now. It's probably more to do with trying to do things on the cheap and save money. Using a 3rd party to make your soles is always going to be way more expensive than doing it yourself. So, brands will sometimes cut corners in order to be more profitable (i.e. use a cheaper rubber compound). I have no idea if Dynafit and Fischer are doing that and I am not making the claim that they are. I just know these soles are quite expensive when done with the right materials and compounds, so it wouldn't surprise me.

 

[patagonialuke]

It's more of what plastics don't stick to rubber. Each plastic (polyurethane, polyamide, polypropylene, etc.) requires an über specific glue and primer to get anything (including rubber) to stick to it. But every brand should have that figured out by now. It's probably more to do with trying to do things on the cheap and save money. Using a 3rd party to make your soles is always going to be way more expensive than doing it yourself. So, brands will sometimes cut corners in order to be more profitable (i.e. use a cheaper rubber compound). I have no idea if Dynafit and Fischer are doing that and I am not making the claim that they are. I just know these soles are quite expensive when done with the right materials and compounds, so it wouldn't surprise me.

Cool, as always, thank you very much for the insight, it's quite helpful.