Alright, in Part I of this series we reviewed the importance of base structure. Now it's time to fine tune the foundation that supports the base: the ski's edge.
Most skis, especially recreational skis, come new from the factory with a 90-degree angle between the base and edge producing a flat ski, meaning that the angles are neither beveled nor acute. This may be suitable for recreational all-mountain skiing but not so on a technically-demanding giant slalom race course where a racer needs to tip the ski onto it's edges and for those edges to hold through the arc on icy, bumpy terrain. The purpose of beveling your edges is to lift the ski's edge ever so slightly off the snow so as not to engage until the ski is tilted on edge. This is critical to a race ski's performance -- especially in the giant slalom discipline. The general rules of thumb for setting up or beveling the edges on a ski for giant slalom racing is that your base edge should be beveled to between 0.5 and 1 degrees and with the side edge angles commonly beveled at 1 to 3 degrees. Determining the proper acute angle is more a matter of preference and ability than it is a set calculation, although some brand manufacturers suggest the base and edge angles that are best incorporated with their models of skis. What I usually suggest is that if you are an advanced-to-expert level skier and you use your skis primarily for racing only you may want to set your base angle at 1 degree and your side edge angle at 3 degrees. If you are more of an intermediate-level racer and you maintain a 'one-ski quiver' -- meaning that your race skis also double up as your all-mountain skis -- then I would suggest you start with a base angle of no more than 0.5 degrees and a side edge angle at a maximum bevel of 2 degrees and try your skis with that setup. You can always add a more acute angle if you want to later.
The process in which you file the edges to the acute angle of your choice is not difficult to learn for anyone who is handy with tools, but you will need a sturdy bench with vises to secure the ski in place in order to file the edges. Base edge and side edge tuning kits can purchased at your local ski shop or from online dealers for around $40.00 for the do-it-yourselfers. If you are not handy (or don't want to shell out for the edging tools and files) you can have your local ski shop tune the edges and setup the angles you specify for around $12.00 to $15.00 a pair. Once your base and edge angles are set and sharp you'll need to maintain their sharpness with a gummi stone and a diamond stone or ceramic stone. Edges must be sharp from contact point to contact point (tip to tail) for carving. A dull or burred edge will not grip the snow and allow the ski to bend into a turning arc properly, thus causing skidded turns. You need to debur and polish the edges after each and every time you take your skis to the hill with the gummi stone and keep them sharp with a diamond stone or a ceramic stone. A gummi stone as well as a ceramic stone can be picked up at your ski shop for around $7.00 while a medium-grit diamond stone will run you approximately $20.00. Whether you tune your edges on your own or have a ski shop tech sharpen your skis it is essential to maintaining sharp, polished edges on your skis with both tools. When using either the gummi stone or the diamond stone be careful not to dull the edges. You want to rub the stones parallel along the flat sides of the metal edges to avoid dulling the edge itself. Keeping your edges polished and sharp will keep them in-tune much longer and help your skis perform at their optimal level.
Now that you have a structure to your base and your edges are setup and sharp it's time to prep the base for the wax of the day. Next week we'll review the process of race-prepping your skis along with picking and choosing the right wax combination to coincide with the weather, temperature and snow conditions you'll face on the race course.
Joe Pinto, Jr.
Wednesday, February 25, 2009
Wednesday, February 18, 2009
The importance of base structure
The first installment in the series on tuning tips involves the importance of base structure.
Base structure is a pattern that is ground into the base of the ski, generally to repel water and break up suction in wet snow as well as provide improved gliding capabilities in cold and very dry conditions. Base structure is also important because it aids in the turning ability of the ski. There are many variable structure patterns to choose from but most fall in the basic category of either linear or cross structures. The depth of the structure is also extremely important and is warranted by varying snow conditions and temperatures. In cold, dry weather a fine structure with a linear pattern is best because the cold, crystalline snow calls for a smoother structure pattern to minimize friction caused by the drier air (low humidity) and on new or fine-grained old snow. A structure of medium depth works well in temperatures right around the freezing point (32 degrees), while a coarse structure provides optimal performance in wet snow and with
temperatures well above the freezing point because the deeper channels repel water and break up the suction created between the ski and snow. But beware of one caveat: a coarse structure does not work as well in colder, drier conditions as the deeper cut structure pattern acutally
increases static friction under these conditions. While a fine, linear structure can be applied by hand using a stiff, steel bristle brush it is best to have a structure pattern applied using a stone grinding machine at your local ski shop. Discuss which pattern would be best for your skis with the technician as he or she will be able to assist you in choosing the one that is best suited for the climate you race in as well as the brand of ski. A fine, broken structure may produce a fast race base on an Atomic GS ski where as a medium depth, cross or broken structure pattern may be best suited on Volkl RaceTigers. Check with the tuning tech for options. And remember this: once the skis have been stone ground it will take numerous cycles of hot waxing, scraping and brushing before the skis will be 'race ready' and able to perform at their optimal level. This process will be discussed later in the series on tuning tips.
Check in again next week for Part II in the series on tuning tips when we will review the importance of the proper base and edge angle on your race skis.
Until next week...
Joe Pinto, Jr.
Base structure is a pattern that is ground into the base of the ski, generally to repel water and break up suction in wet snow as well as provide improved gliding capabilities in cold and very dry conditions. Base structure is also important because it aids in the turning ability of the ski. There are many variable structure patterns to choose from but most fall in the basic category of either linear or cross structures. The depth of the structure is also extremely important and is warranted by varying snow conditions and temperatures. In cold, dry weather a fine structure with a linear pattern is best because the cold, crystalline snow calls for a smoother structure pattern to minimize friction caused by the drier air (low humidity) and on new or fine-grained old snow. A structure of medium depth works well in temperatures right around the freezing point (32 degrees), while a coarse structure provides optimal performance in wet snow and with
temperatures well above the freezing point because the deeper channels repel water and break up the suction created between the ski and snow. But beware of one caveat: a coarse structure does not work as well in colder, drier conditions as the deeper cut structure pattern acutally
increases static friction under these conditions. While a fine, linear structure can be applied by hand using a stiff, steel bristle brush it is best to have a structure pattern applied using a stone grinding machine at your local ski shop. Discuss which pattern would be best for your skis with the technician as he or she will be able to assist you in choosing the one that is best suited for the climate you race in as well as the brand of ski. A fine, broken structure may produce a fast race base on an Atomic GS ski where as a medium depth, cross or broken structure pattern may be best suited on Volkl RaceTigers. Check with the tuning tech for options. And remember this: once the skis have been stone ground it will take numerous cycles of hot waxing, scraping and brushing before the skis will be 'race ready' and able to perform at their optimal level. This process will be discussed later in the series on tuning tips.
Check in again next week for Part II in the series on tuning tips when we will review the importance of the proper base and edge angle on your race skis.
Until next week...
Joe Pinto, Jr.
Tuesday, February 17, 2009
Tuning Tips for Recreational-Level Racers
Hello, fellow racers. As a racer and professionally-trained ski tech with nearly 30 years of experience tuning skis for both racers and recreational skiers, I have volunteered my services
to provide tune-up tips each week on this site. The tips provided will be to help those of you who race gates in the Corporate League on Thursday nights as well as for the 'weekend warrior' who partakes in NASTAR, A.S.R.A. and Masters level racing. Each week throughout the season a new tip will be provided to help both the novice as well as the advanced racer to race prep their skis in order to achieve the optimal performance on the hill. It is said that to be successful in Giant Slalom racing that it is 80% the technical ability of the athlete and 20% the wax and tune-up of the skis on race day that make the difference. While others here with more expertise in the area of teaching technical ability will help you with the 80%, it is my job to shave off those tenths-of-seconds from your run times by giving you the tips to keeping your equipment performing at it's best. This blog is an open forum and welcomes your questions and input at any time, so please feel free to ask me if you have a tuning question or concern with your equipment.
Thanks,
Joe Pinto, Jr.
to provide tune-up tips each week on this site. The tips provided will be to help those of you who race gates in the Corporate League on Thursday nights as well as for the 'weekend warrior' who partakes in NASTAR, A.S.R.A. and Masters level racing. Each week throughout the season a new tip will be provided to help both the novice as well as the advanced racer to race prep their skis in order to achieve the optimal performance on the hill. It is said that to be successful in Giant Slalom racing that it is 80% the technical ability of the athlete and 20% the wax and tune-up of the skis on race day that make the difference. While others here with more expertise in the area of teaching technical ability will help you with the 80%, it is my job to shave off those tenths-of-seconds from your run times by giving you the tips to keeping your equipment performing at it's best. This blog is an open forum and welcomes your questions and input at any time, so please feel free to ask me if you have a tuning question or concern with your equipment.
Thanks,
Joe Pinto, Jr.
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