Sinecure Posted January 14, 2009 Report Share Posted January 14, 2009 I think that base edge beveling helps keep you from catching an edge (and worrying about it). Also, if you don't already lift your forward toe and rear heel, you might try it. You can get a slightly lowered, more stable and strong stance IMO. Good wax and base structure if it is wet will help with speed. Flat base is definitely faster in my experience - provided the board is well tuned. Quote Link to comment Share on other sites More sharing options...
johnstewart Posted January 14, 2009 Report Share Posted January 14, 2009 This is just for fun, because I really could care less and I'm bored. It will make me exercise this brain of mine.I will give you that the coefficient of friction for UMHW may be less than the metal edge material, but lets take into account the amount of the meterials in question. I'm going to be generous and say a single edge is 2.5mm wide. This amount of material is so minimal it isn't worth including in the equation. However, my base I'm going to say is apoximately 200mm wide on the average. Slightly on edge I'm going to say aproximately 50mm of base material is in contact with the snow. Running flat I would have four time the material in contact with the snow, that four times the friction. It doesn't matter how low the coefficient of friction is, it's still four time more. Friction is the enemy when it comes to speed. Ah, this is a common mistake when thinking about friction. The increased area in contact has nothing to do with it. The only thing that matters is the coefficient of friction and the normal force (it's been a while, but I'm pretty sure this is the force perpendicular to the surface). You can have a surface are of an square inch, or a square foot, and the friction will be the same. The area of contact doesn't figure in at all. http://www.school-for-champions.com/science/friction_equation.htm The reason is that as you increase the area in contact with the snow, while there is more in contact, the force that each section is being pushed on is less by a proportional amount. Quote Link to comment Share on other sites More sharing options...
nutmeg Posted January 15, 2009 Report Share Posted January 15, 2009 Ah, this is a common mistake when thinking about friction. The increased area in contact has nothing to do with it.The only thing that matters is the coefficient of friction and the normal force (it's been a while, but I'm pretty sure this is the force perpendicular to the surface). You can have a surface are of an square inch, or a square foot, and the friction will be the same. [...] That only holds for hard surfaces doesn't it? So it probably would only be true if you were running on solid ice. A regular slope is deformed by the snowboard riding on it. Also there is usually some loose material around. Quote Link to comment Share on other sites More sharing options...
johnstewart Posted January 15, 2009 Report Share Posted January 15, 2009 Right; this is idealized. In the real world you do have other concerns. For example, with an edge, you may have the effect of the snow being compressed causing melting of the snow under the edge, whereas you might not if the entire board base is flat. But my point is just that when people think about friction, they often assume that a wider area will mean less friction, but that's not true... it just affects these other outside influences in various ways. On a car, a big wide tire grips the same as a narrow tire... the reason drag racers use big wheels is not specifically for this reason, but other concerns (heat, durability, etc...) Quote Link to comment Share on other sites More sharing options...
johnstewart Posted January 15, 2009 Report Share Posted January 15, 2009 I would posit the reason you get better purchase with underinflated tires is not directly the friction of the surfaces together, but the fact that the knobs can get into nooks and crannies, and stay there. Likewise on a snowboard, the larger surface area helps you plane over the slush, and a smaller board would sink in and get stuck... but the friction between the snow and the board is the same. Quote Link to comment Share on other sites More sharing options...
Neil Gendzwill Posted January 15, 2009 Report Share Posted January 15, 2009 On a car, a big wide tire grips the same as a narrow tire...Only in 1st year physics class. Look at the third response here for a more complex answer. Quote Link to comment Share on other sites More sharing options...
Gleb Posted January 15, 2009 Report Share Posted January 15, 2009 What helps in bombing hills is a board with a side cut radius like my F2 183 Speedster. I think it has like a 16 m scr and it lets you go as straight as you want without much trouble. Plus, the board isn't that stiff so you can make tight turns with ease. I find it impossible to bomb on my SL because the room for error when an edge is caught by the snow at high speeds is very small. Quote Link to comment Share on other sites More sharing options...
Rammy Posted January 16, 2009 Author Report Share Posted January 16, 2009 Thanks for that video Gleb. It made my year. I can't believe this sport has been around for so long and I just found out about two months ago. All we have is the present. Gives new meaning to STRAIGHT AND FAST, lol Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.