Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Do Skis Get Blunt?

brooker.co.za

Post reply on HN
Print view View original

131–140 of 196 posts

Re: Do Skis Get Blunt?

#131

Post by swader999 »

strstr wrote: post #58
amluto wrote: post #24

Earlier quoted context omitted.

It sounds entirely straightforward to do a randomized, blinded test of freshly sharpened vs unsharpened skis. (Okay, the skier can feel the edge or look closely, but a cooperative skier could just not do that for the purpose of the experiment.)

You could also sharpen just one edge of each ski (opposite edges across the pair), then put the skis on random feet. Then see if they can tell which edges are sharp! Most of a typical skier’s weight is supported by the inside edge of the downhill ski while carving. Youth racers tend to ski with one set of edges on the inside for training, and the other edges inside for racing (under the theory that the inside edges t…

In a race, my kids race edge is marked on each ski and he only has those two edges close to his big toes on his race runs. If you don't ski, your a genius if you can figure out how and why this would work I'd imagine.

Re: Do Skis Get Blunt?

#132

Post by abakker »

IsTom wrote: post #78
chrisandchris wrote: post #76

Earlier quoted context omitted.

That assumes that most of the snow is actually fallen from the sky. In central european ski resorts, largest parts of ski lopes are not natural snow anymore (or are mostly mixed natural/artificial). And artificial snow has far more sharp crystals than natural snow.

Shape doesn't matter what the shape is if it's softer than the other material, you can't scratch glass with chalk no matter the shape of it.

minerals in the snow / wind blown grit / rocks / banging around in the ski rack, the lift line, hitting poles, etc.

You're right. Snow isn't hard enough, but, it's probably a mistake to assume it's just snow.

Re: Do Skis Get Blunt?

#133

Post by huskdigselv »

troupo wrote: post #2

Yes, the edge does get blunt. And you can notice it in close up photos. However, does it get blunt enough to affect performance? After all, it's not like a knife trying to cut through a piece of meat

I have been an Austrian trained ski instructor since 2012 and I can tell you that a sharp ski is essential if you want to have carve in any conditions below where the snow isn't slushing or soft. I.e. any run that is either early day, windblown, mid-season (generally colder) or shadow side.

HOWEVER 99% of the skiers on a mountain (and yes I mean 99%) do not actually ski on their edges, they do skidded turns (https://www.youtube.com/watch?v=S4hioJ4ThJA). And the same 99% will typically just slide off of hard and icy parts of a slope as they aren't comfortably riding their edge. To these people sharp edges matter, but less than to the few who successfully carve.

But if you are within that 1% of skiers that do ski mostly on the edge, then a sharp edge is extremely important; you see true carving technique is a delicate skill:

In order to carve properly you need to need to get your skis in a steep angle with the snow, which means you need to get your feet in a steep angle, which can only be maintained if you move your center of gravity into a position that isn't above your feet. Which effectively means your body is in a position that is out of balance. Similarly to how sprinting essentially is just leaning forwards and playing "catch up" with our legs, carving technique tries to do the same. Exception being that we use the rhythmical centripetal forces of turns and the resistance of the snow to create the balancing force (https://d3t7modobimpp4.cloudfront.net/uploads/_1200xAUTO_fit...).

And this is why edges matter; because if the centripetal force provided from the carving turn isn't generated because the skis blunt edges cause them to slip, then instead of generating movement towards the skiers body (reestablishing balance), the skis will drift away from the skiers body (removing balance) resulting in poor turns if not slipping down onto ones hip.

TL;DR: Very good skiers NEED sharp edges to ski well. Most skiers will be fine. (As a matter of fact I think 99% of all skiers will do just fine on ANY ski, and make more significant improvement from 2 days of ski school than any equipment upgrade or tuning that money can buy).

Re: Do Skis Get Blunt?

#134

Post by swader999 »

IsTom wrote: post #78
chrisandchris wrote: post #76

Earlier quoted context omitted.

That assumes that most of the snow is actually fallen from the sky. In central european ski resorts, largest parts of ski lopes are not natural snow anymore (or are mostly mixed natural/artificial). And artificial snow has far more sharp crystals than natural snow.

Shape doesn't matter what the shape is if it's softer than the other material, you can't scratch glass with chalk no matter the shape of it.

I think at a microscopic level, the sharp knife edge on your ski will become rounded after a few runs on ice just from the force involved. You are right, it has little to do with the nature of the snow crystals.

Re: Do Skis Get Blunt?

#135

Post by huskdigselv »

baggachipz wrote: post #97

> Luckily, fixing this kind of damage isn’t hard. I use a 3D printed jig with a 500 grit diamond stone. A couple of glides down the edge is enough to completely clear this up. I don't ski often enough to own my own skis, so I rent them. Having used those rentals in icy conditions, I've had a lousy time due to their shoddy edges. A tool like this would make my day(s) on the slopes so much better. Anybody know of a pla…

A rental should be able to sharpen them if you address it. (And at least here in Europe all rentals sharpen their skis frequently enough).

A good tester is to see if the skis edge grips the surface of your finger nail, the same way you would test a knife or a sharp tool (https://www.youtube.com/watch?v=hHEuV2CPE3w). If it slides across it with no friction, then it's a blunt ski.

Personally, I would advice against trying to tune skis manually, because you might just as easily blunt the edge as you might sharpen it if you don't have a good jig and tools.

Through my 12 years of teaching skiing, I will say that more often than not people who complain about icy conditions are held back by their technique; are you skid steering or carving, because when you are skid steering no level of ski tuning can make your edges stay on hard snow. (Tip: This guy has made an incredible amount of videos about the topic and has even himself progressed from being a skid steering freestyle skier to now being an excellent carver. https://www.youtube.com/watch?v=lwWFlltWQTU).

Re: Do Skis Get Blunt?

#136

Post by swader999 »

MisterTea wrote: post #117

Sharp skis are necessary for good control otherwise you're just sliding around. Snow and Ice aren't the only things you ski over as there is a ton of dirt and other debris mixed in. Sometimes you get rocks and pebbles near trail edges. Heck, spring skiing will put you on trails with thin snow cover in addition to patches of grass and dirt that will destroy your skis (fun fact: hitting grass at speed is NOT fun - inst…

We could talk for pages about wax. Your father is partly right, it does wear off quickly, especially if you apply it correctly.

I'd say wax is important in that it prevents the base from oxidizing. A dried out base is more difficult to turn and slower.

Structure (small grooves in the base) will make you a second faster)

Wearing a race suit vs a normal tight coat will make you two seconds faster.

Proper setup edges vs no tune rounded edges will make you 5-6 seconds faster and with much lower chances of dsq.

The type of wax is much less important. In a slalom race, choosing the best wax vs a less perfect type might only improve you by 0.02 seconds on a sixty second long race.

Re: Do Skis Get Blunt?

#138

Post by cbrozefsky »

JumpCrisscross wrote: post #81
jajko wrote: post #28

Earlier quoted context omitted.

Edges makes bigger difference in ski touring or more appropriately ski alpinism. Meaning tricky steep slopes where you sometimes switch skis for crampons and ice axe and put them on backpack, wildly varying conditions on the slopes. Or using ski crampons when its less extreme. There, any advantage is very important, ie how precisely you put skins on skis to leave that little bit of edge for... edging, at least thats…

> Edges makes bigger difference in ski touring or more appropriately ski alpinism East Coast? I’m a Rocky Mountain skinner and I can’t remember the last time I edged off piste.

East coast touring…. Edges are nice even traversing on piste when you going up after the lifts have closed and the machined dust has been scraped off the hardpack. Also the one time a flexy ski is better on ice, when you gotta traverse a bumped out section…

Also have backcountry nordic pair with metal edges for similiar reason — tho i only debur them, never sharpened.

On piste skinning is mostly because it’s where the snow is until the back country fills in later in the season.

Re: Do Skis Get Blunt?

#139

Post by swader999 »

huskdigselv wrote: post #133
troupo wrote: post #2

Yes, the edge does get blunt. And you can notice it in close up photos. However, does it get blunt enough to affect performance? After all, it's not like a knife trying to cut through a piece of meat

I have been an Austrian trained ski instructor since 2012 and I can tell you that a sharp ski is essential if you want to have carve in any conditions below where the snow isn't slushing or soft. I.e. any run that is either early day, windblown, mid-season (generally colder) or shadow side. HOWEVER 99% of the skiers on a mountain (and yes I mean 99%) do not actually ski on their edges, they do skidded turns ( https:/…

I aggre with this and boots are 90 percent the secret to progress.

You could teach a beginner how to carve on a very flat slope though. The 99 percent that slide are just on too steep of a slope for their carving ability. Which is fine by the way. It's fun to go down steeper runs, even if you arent carving.

Re: Do Skis Get Blunt?

#140

Post by swader999 »

oldandboring wrote: post #110
strstr wrote: post #58

Earlier quoted context omitted.

You could also sharpen just one edge of each ski (opposite edges across the pair), then put the skis on random feet. Then see if they can tell which edges are sharp! Most of a typical skier’s weight is supported by the inside edge of the downhill ski while carving. Youth racers tend to ski with one set of edges on the inside for training, and the other edges inside for racing (under the theory that the inside edges t…

True enough at younger levels but as you move up in age and skill, the weight distribution between the downhill and uphill ski gets closer to 50/50. What you're saying has a kernel of truth and young skiers are still taught downhill ski as a fundamental but shaped skis have really changed the game on this.

No, you never weight each ski evenly. Former WC mogul skier here and even in moguls there's a slight difference in weight on each ski in a turn. Shaped hour glass skis make it easy to turn but you still need more weight on the outside downhill ski.
Post reply on HN