In this three-part series I covered snowboard base dynamics to help prepare your equipment and get a better understanding of how conditions impact riding. In Part One I covered the physics effecting movement on the snow. In Part Two, I covered the snowboard base material, and base structure theory. In this last installment I will cover the role of wax, wax structure, and health and risks.
Part 3: Snowboard Wax
In a simple explanation wax is used between the base and the snow to reduce friction. There are a few different types of friction we try to overcome using wax. When wax is applied to a snowboard base, it is melted and then ironed into a thin layer. When cool, the excess is scraped away and then even more excess is removed from the base with a stiff brush. One can also ‘crayon’ the wax on to the base and use a cork to force the wax in to the pores.
There are many types of frictional forces in physics, but we deal primarily with two forces of friction [kinetic and static] in snowboarding; dry, wet, and sometimes electrostatic.
- Dry friction occurs when the melt-water lubrication is absent or insufficient; this is the case at low temperatures or at low sliding speeds when dry snow granules come in contact with the ski base. Essentially you want wax slightly harder than the snow particles. If a wax is too soft the snow crystal will penetrate into the wax causing a grippy base. However, if the wax is too hard the coefficient of friction will be higher and the base will be less slippery.Kuzmin, Leonid (2010). Interfacial kinetic ski friction (Doctoral). Mid Sweden University, Retrieved December 2, 2014 from http://miun.diva-portal.org/smash/get/diva2:319312/FULLTEXT01
- Wet friction occurs with a high moisture content snow creating suction between base and snow. A fluorocarbon additive is sometimes used to reduce the wet friction. However, it’s important to not use too much fluorocarbon as it will increase the dry friction and reduce glide.
- Electrostatic friction is static electricity generated when a base runs on snow creating an electrostatic attraction between the board and snow. Graphite is commonly introduced into the base to reduce static electric.
The basics of wax
I have tried numerous hydrocarbon waxes out there, most all of them are similar. When I worked as a ski tech at Keystone Resort many years ago, the wax formula was very similar to what it is now. Basically companies were trying to manipulate a paraffin wax hardness to different temperatures and conditions of the snow. Back then, the color of the wax was an easy way to tell the wax hardness. For warmer conditions a wax in the red spectrum was used, and for colder conditions a blue spectrum color was used. This evolved in to virtually every color in between, and the black art of mixing waxes to achieve specific hardnesses for specific conditions was born. Colored waxes today are nothing more than a marketing gimmick to tint the wax, similar to adding a crayon to the mix to offer some mystique.Masia, Seth. (2012) History of Ski Wax, Retrieved November 29, 2014, from http://skiinghistory.org/history/grip-and-glide-short-history-ski-waxKuzmin, Leonid (2006). Investigation of the most essential factors influencing ski glide (Licentiate). Luleå University of Technology
There are basically three types of wax; hydrocarbon waxes, fluorinated hydrocarbon waxes, and fluorocarbon overlays.
- Hydrocarbon waxes are simple paraffin waxes that have varying amounts of oils and synthetic hardeners in them which determine their hardness and what conditions they might be best suited for.
- Fluorocarbon waxes do not mix with hydrocarbon waxes. Fluorinated hydrocarbons are a hybrid link between them. A fluorinated hydrocarbon is not simply a block of wax containing a mix of a hydrocarbon and a fluorocarbon wax. The combination is actually at the molecular level.Moldestad, D. A., (1999). Some aspects of ski base sliding and ski base structure, PhD thesis, Norwegian University of Science and Technology.Lehtovaara, A., (1989). Kinetic friction between ski and snow, PhD thesis, Tampere University of Technology, Finnland.
- Fluorocarbon overlays are the most expensive sprays, powders, and blocks. These products do not penetrate the base the way hydrocarbon waxes do and are also more challenging to work with.
This is the most basic of waxes. These waxes are primarily made up of three types of hydrocarbons: paraffin, microcrystalline, and synthetic waxes that are combined together in various proportions. Paraffins are soft, candle-like waxes, that have low coefficients of friction allowing the board to glide easily over the snow crystals. Microcrystalline waxes are a branched type of hydrocarbon that are more durable than paraffins and do not wear off as fast. Synthetic waxes are slightly branched hydrocarbons that also make the wax stronger. All waxes use a hydrocarbon base to which various additives are incorporated.Coupe, Richard (2008). An Investigation Comparing the Efficacy of Different Lubricants for Skis on Artificial Snow. The ACES Journal of Undergraduate Research, Sheffield Hallam University.Giesbrecht, Jan Lukas (2010). Polymers on snow: Towards skiing faster (Doctoral). Swiss Federal Institute of Technology
It was Terry Hertel that developed and introduced a fluorocarbon wax to the ski industry in the late 1980’s. Hertel owns several patents on glide wax,Hertel, Terry (1992) US Patent US 5114482A http://www.google.com/patents/US5114482 although it’s not as much of a secret as one would imagine, a spectroscopy and CHN analysis does reveal a breakdown of the contents. Elemental analysis can be qualitative (determining what elements are present), and it can be quantitative (determining how much of each are present). While toxicity levels are low, many of the waxes on the market today contain them. Fluorine is the most electronegative of all the elements. When substituted for one or more hydrogen atoms in a hydrocarbon wax, the new fluorocarbon wax becomes incredibly hydrophobic, which is why it is great as a snowboard wax. Usually some degree of fluorocarbon or surfactant is in the common wax ingredient. Hence began the ‘all-temperature’ waxes, basically a wax that would perform from 5°F to roughly 50°F. Although, that is subjective to actual snow snow-structure, age of the snow, and water content in the snow. Temperature, while a main factor, is not the only factor.Pihkala, P.; Spring, E., (1986). Determination of the contact area between ski and snow using a simple thermal conductivity meter, Report Series in Geophysics, University of Helsinki: Helsinki.
Which wax to use
Sometimes you have to choose your own toppings on your pizza. I try to use a natural wax when the conditions permit. For the most part, I use Purl wax, depending on the conditions. I also use Hertel Hotsauce wax even though I have my concerns knowing what is actually in the makeup of the wax. Generally wax gives you more control in to turns, and makes glide easier. Speed however, is less of a concern to me in the backcountry. The coefficient difference between an eco-friendly and a toxic fluorocarbon wax is very, very minimal. The durability is virtually the same between the two.
With that said, there is really no reason any recreational user needs to resort to a wax containing fluorocarbon or other added toxins when the technology and manufacturers are starting to step up to the environmental impacts of various waxes. Whichever wax you choose, be vigilant to heat the wax iron just enough the drip the wax. DO NOT allow the wax to smoke, or breath in the fumes! Preheat the iron for awhile to get the lower setting up to a suitable temp. Never apply the iron directly on to the polyethylene base without wax as this can damage the base pores. Use fiberlene between the base and the iron if necessary.
I believe structure is more important than wax type, unless you are racing to achieve a difference of seconds in speed. Matching a finer structure on both the base and the wax during cold temps, and a more course structure during warmer temps is more of a concern. Copper and brass brushes are typically used prior to waxing to prep the surface. Stiff metal and / or steel brushes should not be used and are an obsolete technique. The wax structure brush you choose will make a big difference in performance. The all-purpose nylon brushes achieve the majority of structures. These bristles are course however, and will not remove wax in the finer structure. Horse hair and other finer bristle brushes can accomplish fine structure.
A clothes or steam iron from a thrift shop will work just fine. Many wax manufactures claim that a manufactured waxing iron is the only way to control heat. I have actually found the opposite to be true. Out of curiosity, I used an infrared temperature monitor on three types of leading wax irons and the temp fluctuations, while minuscule, were all over the map. The clothes iron maintained heat within two degrees constant.
There are literally hundreds of videos and articles out there that show various techniques for waxing. The process is somewhat the same; prep, drip wax, spread wax, scrape, structure, and tune. I will very briefly touch on basics and emphasize key points that are often not mentioned.
Prep the base surface with a brass or copper bristle brush (not steel). This opens the pores and gets rid of impurities that may have worked their way in to the base. Remember you should wear a respirator when brushing or hot-scraping a wax that contains fluoros.
Clean the base thoroughly with a citrus cleaner and wipe all the impurities from the sintered base using a Scoth-Brite pad — gently, especially residual traces of glue from skins which will always work their way in to the pores. Keeping your base in good shape will prolong the life of the skin glue as well. Citrus cleaners found at auto parts stores will do the trick. I use a 20x concentrate and mix my own in a spray bottle. Dawn dish soap is another choice – diluted with warm water. Don’t fall for the marketing gimmick of toxic base cleaners.
Inspect for micro-hairs from the polyethylene base that will cause friction. If present, remove them gently with a steel scraper or Scoth-Brite pad. Follow over the area with an Omni pad.
Warm the iron to the lowest setting that will allow the wax to melt and drip. DO NOT allow the wax to smoke or breath fumes. Organofluorine breakdown products in heated wax are extremely toxic (see ‘Environmental and health concerns’ & ‘Caveat emptor’ sections below).
Drip the wax on to the base surface. With the iron at a low setting move the melted wax across the surface.
Spread the wax on to the base surface with the coolest setting possible while still maintain wax spread. Never allow the iron to touch the base without wax, this will damage the pores (e.g. heat sealing). If you are using a higher temperature wax you should use fiberlene between the base and iron.
Scrape the wax with a plastic scraper from tip to tail in one motion. You want continuos straight lines. Do not use a metal scraper for removing wax. Keep your plastic scrapers sharp using a metal one. Lock the plastic scraper into a vise and starting at the far side, drag the metal scraper towards yourself in a relatively quick but controlled manner a few times. Good as new!
Using a nylon structure brush, go straight from tip to tail to add or enhance structure. For fine structure you can follow this in succession with a fine horse hair structure brush.
Last step if necessary; debur and tune edges. Since this splitboard has a rocker, I detune a bit on the rocker areas with a demon stone.
In the previous section I covered structure theory, and the different types of structure for conditions. The same principle holds true for waxing; the smaller the snow crystals, the finer the structure required and visa versa. Likewise, in cold, dry snow such as the Rocky Mountain region (20°F and below), the structure should be fine and shaped to hold minimal water for the conditions. On cold crystalline snow (10°F and below), the base should be as smooth as possible so the points of friction are minimized. On amorphous, wet snow (20°F and above), a coarser structured snowboard base is better to minimize the points of friction. The idea is to move the free moisture away from the base and reduce suction. It is important to mention that a course structure is somewhat permanent.
Environmental and health concerns
I realize this isn’t going to be a popular topic to many out there, especially to those in the competition and manufacturing sectors. However, this is a broad message to all users, both recreational and professional. The common bond we all share is the passion for the mountains. With that said, we should all be stewards to the environment and do our part to protect what we are passionate about. The concerns about fluorinated waxes stem from the production process. There are many wax companies developing more eco-friendly waxes that are safer for the environment. Despite that, many of the wax companies basically deny any plausibility, the facts are there, and these companies are doing nothing more than protecting themselves and their profits. There is big money in competitive ski and snowboard races, and often these competitions are won by fractions of a second. You can quickly put the dots together and follow the underlying motives of these companies. Manufacturing fluoro products requires some nasty chemicals, including perfluorooctanoic acid (PFOA). These chemicals have ended up in the water streams near Dupont and 3M production facilities and have affected thousands of people. Ski and snowboard wax is a minuscule part of the bigger picture of fluorochemical processing. See the Environmental Protection Agency’s lawsuits against fluorochemical manufacturers in the US.U.S. Environmental Protection Agency, (2013). Perfluorooctanoic Acid (PFOA) and Fluorinated Telomers, Retrieved November 29, 2014, from http://www.epa.gov/oppt/pfoa/.
The exact contents of the waxes are seldom revealed by the manufacturers, but it has been shown that many of the glide waxes available on the market contain semifluorinated n-alkanes (SFAs) and perfluorinated carboxylic acids (PFCAs). Application of glide waxes to snowboards, downhill and cross country skis is performed in a similar way using an iron to melt the wax onto the base of the ski.Kärrman A, Ericson I, van Bavel B, Darnerud PO, Aune M, Glynn A, Lignell S, Lindström G. (2007); Environ Health Perspect. 115(2): 226-230 This procedure causes a lot of smoke and fumes containing a blend of gaseous organofluorine compounds which are easily inhaled by the worker.Yeung LWY, Miyake Y, Taniyasu S, Wang Y, Yu HX, So MK, Jiang GB, Wu YN, Li JG, Giesy JP, Yamashita N, Lam PKS. (2008); Environ Sci Technol. 42(21): 8140-8145Young CJ, Furdui VI, Franklin J, Koerner RM, Muir DCG, Mabury SA. (2007); Environ Sci Technol.41(10): 3455-3461 Inhalation of organofluorine breakdown products are known to induce pulmonary edema and polymer fume fever, informally called Teflon Flu.Loewen M, Wania F, Wang FY, Tomy G. (2008); Environ Sci Technol. 42(7): 2374-2379Dinglasan MJA, Ye Y, Edwards EA, Mabury SA. (2004); Environ Sci Technol. 38(10): 2857-2865 Reduced fecundity have been observed with levels of PFOA found in the general population as well as developmental toxicity,Russell MH, Berti WR, Szostek B, Buck RC. (2008); Environmental Science & Technology, 42(3):800-807 and hormonal disruption.Martin JW, Chan K, Mabury SA, O’Brien PJ. (2009); Chemico-Biological Interactions. 177(3): 196-203 In addition, fluorotelomer alcohols demonstrate estrogen-like properties.Hart K, Kannan K, Isobe T, Takahashi S, Yamada TK, Miyazaki N, Tanabe S. (2008); Environ Sci Technol. 42(19): 7132-7137 PFOA has been detected in industrial waste, stain resistant carpets, carpet cleaning liquids, house dust, microwave popcorn bags, water, food, some cookware and PTFE such as Teflon®.
The bottom line is this, most backcountry enthusiasts are not concerned with fractions of a second in speed. Recreational users in general do not need this advantage. There are plenty of waxes out there such as Purl (purlwax.com) that are completely green and safe to apply and use. Furthermore they have less of an impact on the environment. I have provided more than 150 additional citations for further reading (cited below in References). You simply cannot deny the science and studies that are out there. I would urge other backcountry and recreational users to keep in mind the industry practices you are supporting by purchasing products.
This concludes the three-part series. In Part One I covered the forces effecting movement on the snow. In Part Two I touched on base construction, and base structure theory. The physics of this series can be complex, but it’s actually easy to understand. With a basic understanding of the dynamics involved you can prepare your equipment and have a better understanding of how conditions impact riding.
References [ + ]
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