sidecut design

[jtslalom]

I was wondering if anybody knows which conic section a sidecut is designed around, hyperbola, parabola, or circle. I don't know much about how manufacturers come up with their sidecut radii, but since the word radius is always used I would assume the sidecut is designed aroun a circle.

[nils]

we use circles of different radius on each model...12.1-12.7-13.3m

Nils

[philfell]

To make a very long answer short... all of the above mentioned. Different manufactures use differ sidecut geomatry. The ones that don't use a circle take an average and use that number as their "radius".

[Jagger]

Now let me see if I've got this right. If I was building a board with a 14 M radius based on a circle to make said radius I could take a 14M length of string nail it to something tie a pencil @ the other end and lay whatever I'm using as a template at the pencil end of the string I could draw my side cut on my template. Is this correct?

[nils]

it is correct
the 14m radius of the board is part of a 14m circle viewed from above :)

[NateW]

Yes, that's the theory. But, when my friends and I tried to use the same method to draw the radius for a halfpipe or quarterpipe we found that real string stretches way too much to be useful. :)

[Jagger]

Nate last 1/4 pipe I built was in like 1983 an that was how we did it. I just wasn't sure that that was the Idea behind board radius.

[Gecko]

Originally posted by NateW
Yes, that's the theory. But, when my friends and I tried to use the same method to draw the radius for a halfpipe or quarterpipe we found that real string stretches way too much to be useful. :)

Back when I was building boards for Flite Snoboards we solved the stretch problem by using 250lbs (or 800lbs) test Kevlar kite string ( I also fly a stack of Flexifoils)...we'd go to the beach early in the morning in august and pound a nail into the asphalt and measure out the radii we wanted and mark them on a piece of mylar then back to the shop we'd go...