This thread discusses the Content article: Snowboard Mold Setup - Part 5

Discussions on the Snowboard Mold Setup video should go here.

I built my mold rib slats out of a lot of 1/4 x 1/4 in. MDF. Should I be worried about the thickness of these throwing off the curve of the mold ribs? I believe, because the shape of the ribs is a "W" essentially, the curve would be exaggerated at the ends. When you built yours, did you offset the curve 1/4 in. first to compensate for this, or is it not too much of a big deal?

You bring up a really good point and it's an issue I haven't quite figured out yet. The challenge is calculating how to compensate. The curves are essentially offset by the thickness of whatever you put on top of the mold ribs so they are hardly impacted. However, the running length of the snowboard will shrink because we are effectively closing in on the center of the board from the tip and tail. It's hard to determine exactly how much running length shrinks because it depends a lot on the radius of the nose and tail. I think the steeper the nose and tail climb the more significant the impact will be on running length.

Right now I just extend my running length by 2x my surface thickness but this is overly simplistic and I'd like to get more exact.

If anyone out there comes up with a more accurate method for calculating this please let me know. I'd be happy to make it a calculator that everyone can use.

I dusted off the trigonometry a little, but didn't come up with much. So basically the only parameters that would be offset would be the tip and tail length correct? Wouldn't the overall board length be effected, not the effective length because you are actually increasing the radius of the curve between your feet? I think if anything the effective edge would increase by less than two times the surface thickness.

Have you found any difference in camber height and effective edge from what your plans predict?

It should all be proportional though. You might want to just measure one of your boards versus what it's supposed to be, and come up with a ratio per parameter.

I think you might be right about 2x being too much. Attached is an image that lead to that line of thinking but it's only valid for the points indicated.


I think the real difference is in running length. The nose and tail would still be the same length but they would begin elevating before they are supposed to. The overall board length will remain the same because we are not stretching or shrinking it (the base material is cut and the edges are attached).

As for measuring... it's not a clean measurement to take because it's tough to identify the exact point where the curves begin and end.

I've got a free pack of inserts for the first person to definitively solve this conundrum with a replicable, verifiable calculation

I think I figured it out. When I was saying Effective Edge, I meant the distance between the rear contact point and the front one. When you have a camber on your board, you are creating a curve in the middle of the board which is being accentuated. Because the tip and tail radii are being lessened, this cancels out, although you have reproportioned the regions of the board. The center part, between the points where the board contacts the snow is widened, while the tip and tail are shortened.

Hope this confusing proof helps.