Is this is stupid idea?

[Loran]

On his blog he added the following comment :

Hei igjen – ja det kan hende jeg får folk på nakken – men se det positive i det – mindre jobb og mer tid til å gå på ski Vi grunnprepper våre ski mindre enn det vi har gjort tidligere pga kvaliteten på slipene som vi får. Det betyr ikke at har helt stoppet med metting av ski. I mine samtaler med forskere har de henvist til det lille som eksisterer om skisåler og metting i vitenskapen. Det som er kommet frem er at flere innvarminger med relativ høy varme er bedre enn varmeskap med relativ lav temperatur. Sålen i seg selv er ultra high molecular weight polyethylene – et hydrofobt materiale som har enkelte tilsettingsstoffer. I sålen argumenteres det for at det finnes amorfe soner som trekker til seg glider – spørsmålet da er – hvor dypt? Hvor god er heften? Hvor mange ganger for å få maksimal gevinst? Sjekker du Kuzmin så skriver han mye interessant som er stikk i strid med det mange mener – men det er interessant lesing.
Ang fart på jernet – høres ut som du gjør det rett! Lykke til!

Which someone could please translate better than google. Yet Googletranslate says
"...What has emerged is that more waxing with relatively high heat is better than a heating cabinet at a relatively low temperature..... Check Kuzmin, he writes a lot of interesting that contrary to what many believe - it is interesting reading..."

[MN Hoser]

I think the discussion is if the "old" method of extensive base prep is needed vs. an abbreviated method. Early on, I was suggesting that it might be better to use a hot box for "blue waxes" rather than soft "red or yellow waxes." This is purely from my perspective on OUR snow. We tend to have very sharp, cold snow (except for when we don't ) I think the discussion has moved a bit more towards "what are they doing on the world cup?" It seems like the World Cup is on warmer snow than WE have here in MN.

I'm not sure I'm changing what I'm what I'm doing until I hear some more evidence to convince me the extra work is not needed.

Jay

[osloskier]

@Loran - Translation:

Hi again - I might be stirring up a hornet's nest here - but look on the bright side - less work and more time for skiing We base prep our skis less than we used to due to the quality of the grinds we get. That doesn't mean we've completely stopped saturating skis. In my discussions with scientists they have referred to what little science exists about ski bases and saturation. It appears that several passes with the iron at relatively high temperature is better than hot boxes with relatively low temperature. The ski base itself is UHMWPE - a hydrophobic material with a few additives. Some argue that there are amorphous zones in the base that attracts glide wax - the question is then - how deep? How well does it stick? How many times to get max effect? If you check out Kuzmin he writes a lot of interesting stuff which is quite the opposite of what many others believe - but it's interesting reading. Re the speed of the iron - sounds like you're doing it right! Good luck!

MN Hoser - there's plenty of cold snow in the world cup. -18 C is the limit for national competitions in Norway. Sweden, Finland and large parts of Russia are as cold or colder.

I think Nystad's comment is very interesting. Better grinds require less waxing? Seems to support my favourite hypothesis that it's not the UHMWPE that needs the wax, but the grind that needs smoothing. Also I think many people don't realize that sintering is not just a way to get a porous material. It can produce such materials, but the product does not have to be porous. You can also use sintering to avoid disturbing the grain orientation of the material. When extruding, long molecules tend to line up in the direction of extrusion, and UHMWPE consists of ultra long molecules. Work hardening might also be a factor. Sintering would avoid such effects, and this could have a huge impact on how the material responds to grinding. So there can be very good reasons for sintering ski bases even if porosity is unimportant.

[osloskier]

I found this PhD dissertation from 2010 yesterday: http://www.polytech.mat.ethz.ch/researc ... brecht.pdf

This seems like solid work and he gets some very interesting results. For example, when testing a range of different polymers of varying hydrophobicities from fairly hydrophilic to very hydrophobic, he finds huge differences when the ski base is completely smooth, but even just a little structure removes almost all the difference. Even if it doesn't discuss various waxes, it does discuss hydrophobicity, chemical compositions and structure and their relative importance, and it shows how scientists think about friction on snow.

[MN Hoser]

Oslo, interesting paper. I paged through it, but didn't read it. (Later.)

I don't know if I believe teams on the World Cup are grinding skis, doing a short prep (1 day) and then racing the next day on the World Cup at -18C (or -16C). I think the purpose of the base prep and skiing on skis is to smooth the base more than put wax into the base. I tried a new grinder this year, and their grinds look much cleaner than my old grinds, so maybe I'll be converted. It's hard for me to tell if white bases in cold abrasive conditions are due to a microscopically rough surface that is losing wax, or if the wax is being stripped from the ski, or if the petex is being abraded by the snow. I kind of think it's the first one.

At warmer temps (where you actually slide), I believe there is much less need to smooth the base unless the snow is new, and then it can depend on the type of new snow. In wet snow (below and above freezing), I bet that new grinds are often faster than old, but these are just my guesses.

There are a number of people around here that keep old, smooth skis for the races at -20C. Once they find something that works in cold temps, they never give it up. Also, we don't have an ocean around here. We do have Lake Superior, but I wonder if a lack of water makes a difference in the type of snow we get compare to Norway and Sweden. I can see where Russian might have a similar climate to Minnesota.

Jay

[Loran]

Thanks for the translation. May I ask for another ?

This Comment from Knut at http://knutnystad.com/about/comment-page-1/#comment-860

Hei og takk for spm. Vi har testet denne metodikken opp mot det vi gjør, MEN for vårt formål har vi alltid noe som er bedre. Det vi ser er jo at alle glidere taper seg over tid (det seg være slitasje eller oppsamling av smuss). Det kan nok tenke seg at etter x antall km så krysser metodikkene – dvs at Kuzminmetoden – blir bedre enn tradisjonell smørning, men vi har ikke testet om dette er 20 eller 40km. På lengre løp har vi skibytte og dette er ikke så relevant for oss. MEN når det er sagt. Stålsikling har sune fordeler. Den gir fersk såle, en plan såle, og en struktur – alt dette er bra. Selvsagt krever verktøyet at man er stødig på hånden, men den kan være et godt alternativ for mange. Jeg har personlig tro på at det er bedre å tenke på en slik sikling som et verktøy, og at man bør tenke at det er ikke enten eller – hvorfor ikke kombinere med tradisjonelle smørningsmetoder? Vi bruker et tilsvarende verktøy. Han har laget en webside som gir mye info om produktet. Besøk siden som heter http://www.norskeski.no – dette er et meget bra verktøy!! Håper du fikk litt hjelp av svaret – lurer du på mer får du bare ta kontakt. God helg.

What I get from Google Translate is that He sort-of acknowledges what Kuzmin says : A regular "world cup" class prep is better but not for long. They don't care because its enough for what they need. They will swap skis before glide is worsening. (On a 50km WorldCup skate race, they are allowed to swap every 8 km, right ?) Does he say that
for long distances Kuzmin approach is probably better ?

[osloskier]

Sure.

Hi and thanks for asking. We have tested this method against what we're doing, but for our purposes we always have something that works better. What we're seeing is that all glide waxes deteriorate over time (whether due to abrasion or dirt pickup). It may well be that after x km the methods cross - i.e. the Kuzmin method gets better than traditional waxing - but we have not tested whether this happens at 20 or 40 km. In longer races we are allowed to switch skis so this is not very relevant for us. But that said, steel scraping has its advantages. It produces a fresh sole, a flat sole, and a structure - all this is good. Obviously the tool requires a steady hand, but it can be a good alternative for many. I personally believe that it's better to think of such scrapers as a tool, and that one should think that it's not either / or - why not combine with traditional waxing? We are using a similar tool. He [osloskier's remark: referring to the inventor of the similar tool] has made a web page that provides a lot of info about the product. Visit his page at http://www.norskeski.no - this is a really good tool!! I hope you got some useful info - if there's anything else get in touch. Have a good weekend.

[Loran]

Thanks !
What do you think is meant by "cross" ? does it refers to the Xriller ?

[osloskier]

Assume you mean "It may well be that after x km the methods cross"?

He's thinking of the glide vs distance curve of Kuzmin vs the same curve for waxing, and that the Kuzmin curve crosses the waxing curve after some number of km. I.e. he thinks it's possible that Kuzmin deteriorates at a lower rate than wax, and therefore becomes better than waxing after some time. They never get to this point because they are allowed to switch skis before it happens.

My own conclusion from using Kuzmin for 3 or 4 seasons is that I get better results with Kuzmin and that scraped skis last unbelievably long, many times longer than I've ever achieved with stone grind and wax. But I never have optimal skis anyway except by pure luck, because I don't waste my time testing multiple pairs of skis in the track before I ski. I'm just skiing for the pleasure of it, not to beat anyone. So I never know for sure what would be the ideal prep. Nystad and his guys don't know that beforehand either, they will test 10 to 15 pairs before each race because even they can't guess and get it right. I only have two (soon to be three) good classic pairs to choose from anyway, and those are 1 pair for cold, 1 zero pair and 1 klister pair. Which pair I choose is determined by other factors that are more important than the prep. Scraping lets me switch structures when the weather report says that my current structure will be all wrong for some days, and this helps noticeably compared to only having a single structure available for each pair. I also use a manual structure tool (red creek rollers) in addition to Kuzmin's U and + scrapers for moist and wet conditions as Kuzmin does not work well for wet conditions without additional structure.

I just want nice glide, good enough to keep double poling while being able to concentrate on technique, to feel that I'm flying across the flats, and to scare myself a little on the downhills. My career does not depend on having at least as good glide as the rest, and if there's a snowfall during cold weather I and everyone else will have crap glide until it turns milder anyway :)

So for me, Kuzmin has been a revelation. So much less work, so much more skiing. I honestly can't tell much of a difference, except that my skis were worse when I didn't have the time to wax them often enough, and being able to easily switch structures helps too. To qualify "can't tell much of a difference": My informal glide tests performed on different but similar days do not reveal any difference between new Swix LF wax and Kuzmin. I will certainly never go back to waxing for training skis.

Nystad more or less confirms my view, I think - he says that Kuzmin can be a good alternative for many. That certainly means that it works better than not waxing often. I'm guessing that to beat Kuzmin you have to wax after every outing and likely use more advanced products than LF wax.

[MN Hoser]

I listened to a wax talk last night by one of the wax techs for the US Ski Team. I didn't take notes at the time, so beware of my memory. I might remember some things incorrectly. Also, he was presenting in a ski shop, so I assume he is aware of what he said would drive sales (both plus and minus). Finally, he's selling wax (Mantra), which are one of the waxes they use for the team. So with those disclaimers...

As for hot boxes, I got the feeling they don't use them or don't use them much. They base prep with CH6 or beta red, maybe four layers (scrape and brush). Then it's usually a LF graphite like SkiGo, and a couple layers of HF. For colder conditions they may do more. I asked about going directly to pure fluoros (something I heard teams are trying) and he said that they tested it, but that the wax job doesn't last. He told a story that the Norwegians were cleaning and storage waxing with high fluoro paraffins, and after a while they found the skis were not holding wax. They've since moved to LF waxes. (The US team uses hydrocarbon, not LF.) This is for cleaning and storage.

Another thing that was interesting is that they usually do a high fluoro paraffin, pure fluoro powder, and then they test blocks, an then liquids over the blocks (which are over the powders). They also test liquids and blocks alone (over the powders). I asked about blocks or liquids slowing the ski and it's rare. They iron at one temp, hot, whatever the iron goes up to I believe. So 170 or 180. One light pass to "tamp down" the powder. So not a tamping but running the iron down the ski with the front end lifted. Then it's two passes, one on each side of the groove.

He showed how to apply grip wax, and I can't believe that I didn't know how to put on soft grip wax without leaving a lump on the side of the cake. A discussion of hairies and that grip wax should grip just enough so you slip occasionally, otherwise the skis will be slow.

After the presentation, he started giving out door prizes. A couple hats, a wax apron, a couple more hats. Then holds up a vial of pure fluoro (Mantra Snow White), and calls my name. Holy ----, really? The retail on it is $250, so I'm interested in racing in falling snow around 30F.

That's it for now,

Jay

[osloskier]

I re-wrote my last post a little. I didn't get it quite right last night :)

[Blah]

Randy does great wax clinics! Just to add to that the one time I don't run blocks is in brand new cold snow. Powders tend to be faster alone.

[Blah]

Oslo, interesting paper. I paged through it, but didn't read it. (Later.)

I don't know if I believe teams on the World Cup are grinding skis, doing a short prep (1 day) and then racing the next day on the World Cup at -18C (or -16C). I think the purpose of the base prep and skiing on skis is to smooth the base more than put wax into the base. I tried a new grinder this year, and their grinds look much cleaner than my old grinds, so maybe I'll be converted. It's hard for me to tell if white bases in cold abrasive conditions are due to a microscopically rough surface that is losing wax, or if the wax is being stripped from the ski, or if the petex is being abraded by the snow. I kind of think it's the first one.

At warmer temps (where you actually slide), I believe there is much less need to smooth the base unless the snow is new, and then it can depend on the type of new snow. In wet snow (below and above freezing), I bet that new grinds are often faster than old, but these are just my guesses.

There are a number of people around here that keep old, smooth skis for the races at -20C. Once they find something that works in cold temps, they never give it up. Also, we don't have an ocean around here. We do have Lake Superior, but I wonder if a lack of water makes a difference in the type of snow we get compare to Norway and Sweden. I can see where Russian might have a similar climate to Minnesota.

Jay

They are grinding between just about every race on the WC. The fastest skis are those with fresh base material.

[nxski]

Oslo, interesting paper. I paged through it, but didn't read it. (Later.)

I don't know if I believe teams on the World Cup are grinding skis, doing a short prep (1 day) and then racing the next day on the World Cup at -18C (or -16C). I think the purpose of the base prep and skiing on skis is to smooth the base more than put wax into the base. I tried a new grinder this year, and their grinds look much cleaner than my old grinds, so maybe I'll be converted. It's hard for me to tell if white bases in cold abrasive conditions are due to a microscopically rough surface that is losing wax, or if the wax is being stripped from the ski, or if the petex is being abraded by the snow. I kind of think it's the first one.

At warmer temps (where you actually slide), I believe there is much less need to smooth the base unless the snow is new, and then it can depend on the type of new snow. In wet snow (below and above freezing), I bet that new grinds are often faster than old, but these are just my guesses.

There are a number of people around here that keep old, smooth skis for the races at -20C. Once they find something that works in cold temps, they never give it up. Also, we don't have an ocean around here. We do have Lake Superior, but I wonder if a lack of water makes a difference in the type of snow we get compare to Norway and Sweden. I can see where Russian might have a similar climate to Minnesota.

Jay

They are grinding between just about every race on the WC. The fastest skis are those with fresh base material.

That's definitely not the case for the Canadian team. They are of the mindset that a base saturated with wax is the fastest base.

[Blah]

Oslo, interesting paper. I paged through it, but didn't read it. (Later.)

I don't know if I believe teams on the World Cup are grinding skis, doing a short prep (1 day) and then racing the next day on the World Cup at -18C (or -16C). I think the purpose of the base prep and skiing on skis is to smooth the base more than put wax into the base. I tried a new grinder this year, and their grinds look much cleaner than my old grinds, so maybe I'll be converted. It's hard for me to tell if white bases in cold abrasive conditions are due to a microscopically rough surface that is losing wax, or if the wax is being stripped from the ski, or if the petex is being abraded by the snow. I kind of think it's the first one.

At warmer temps (where you actually slide), I believe there is much less need to smooth the base unless the snow is new, and then it can depend on the type of new snow. In wet snow (below and above freezing), I bet that new grinds are often faster than old, but these are just my guesses.

There are a number of people around here that keep old, smooth skis for the races at -20C. Once they find something that works in cold temps, they never give it up. Also, we don't have an ocean around here. We do have Lake Superior, but I wonder if a lack of water makes a difference in the type of snow we get compare to Norway and Sweden. I can see where Russian might have a similar climate to Minnesota.

Jay

They are grinding between just about every race on the WC. The fastest skis are those with fresh base material.

That's definitely not the case for the Canadian team. They are of the mindset that a base saturated with wax is the fastest base.

About every other interview Harvey throws his techs under the bus so maybe they should be grinding
This is info from the Salomon and Rossi race guys as well as the Start Techs. Maybe Canada isn't doing it because they don't have a machine with them like Norway and Sweden.