Where to put my waist.
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Where to put my waist.
i am making my first pair of skis. they are to be 180cm long and have the dimensions of 130-100-120. now 100 is the waist width, just where do i put it on the ski, Ex. 100 cm from tip. please give me your input.
General consensus is to work out the running length (amount in contact with the snow) and place the waist at 55% of the running length from the tip.
Eg. For a 180cm twin tip the tip and tail will be 15cm long each. So the running length will be 150cm. 55% of that is 82.5cm. So waist should be 82.5cm from the start of the running length (or 97.5 from the ski tip). Boot centre is usually placed at the waist point also.
Eg. For a 180cm twin tip the tip and tail will be 15cm long each. So the running length will be 150cm. 55% of that is 82.5cm. So waist should be 82.5cm from the start of the running length (or 97.5 from the ski tip). Boot centre is usually placed at the waist point also.
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If you're doing a circular sidecut, you can't move the waist given some pre-determined width dimensions. They define where the waist will be, its just geometry. If you want to move the waist fore/aft, you have to change either the tip or tail width. If you make the tail narrower, it moves the waist back for instance.
you are a retard, you obviously dont know what point i am trying to make.Dtrain wrote:I snowboard.....butyou should definatly figure out what a ski is before you attempt to make one. The waist width is skinniest part of the ski and depending on your personal preference, located at or around the planned boot center.
hum.. this is your 2nd message rybutler... a "thanks for those helpful replies" would have been a better start to show some respect for the guy who gave you an actual answer !
Even though DTrain's reply was a bit rude, we see so many people not reading the posts and directly asking stupid question that I cannot blame him. If you think people are gonna help you again with this attitude I think you're wrong !
Even though DTrain's reply was a bit rude, we see so many people not reading the posts and directly asking stupid question that I cannot blame him. If you think people are gonna help you again with this attitude I think you're wrong !
A bad day skiing is always better than a good one at work...
Anywhere between 2 to 5 cm back from true center, so in your case 92-95 cm back from the tip. Read more, as in everything on this forum, post less.
Fighting gravity on a daily basis
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rybutler wrote:you are a retard, you obviously dont know what point i am trying to make.Dtrain wrote:I snowboard.....butyou should definatly figure out what a ski is before you attempt to make one. The waist width is skinniest part of the ski and depending on your personal preference, located at or around the planned boot center.
I do know what point you are making! I too have asked a couple of these gentlmen to hold my hand and guide me though my ignorant or brain dead building thoughts, and I read these forums/journals for almost a year before i even asked a question.
But even this retarted knuckle draggin' snowboarder knows where he would want his waist width on ski. Any where I preffered it. If you dont even have a thought or prefferance to the easiest of design specs, you should not even be reading this stuff. You belong at a mainstream sports outlet getting advice on what to buy, not what to build. My answer to your question was blunt but true. And If you were trying to make a point with that question, I dont think anyone got it. I can already see your next question....."where do I want me boot center?".
Twizz is right. If you have a predetermined tip and tail width and you put your predetermined "waist" in a certain spot it won't actually be the real waist (narrowest point of the ski). I did this on the first few designs before realising that the real waist was behind the place where I thought I had put it.
My latest design I chose a running length and a sidecut and placed the apex of the circle at my waist point. This waist point and sidecut then defined the tip and tail widths.
You realise after a while that all the parameters are linked and the physical realities of geometry mean you can't define all the parameters independently.
My latest design I chose a running length and a sidecut and placed the apex of the circle at my waist point. This waist point and sidecut then defined the tip and tail widths.
You realise after a while that all the parameters are linked and the physical realities of geometry mean you can't define all the parameters independently.
Don't wait up, I'm off to kill Summer....