Shorter Race/Freerace boards

[shawn13]

Ive thought about the foil but am not ready to make one yet. I thought I would start off with a course board that is less technical. I have enough volume to construct a Monaro Slalom which I may decide to do first, but I figured if my custom design worked I would just build that instead. The size of the board would benefit for my needs if it did work.

I have all the supplies i need including tuttle fin boxs. The only thing i need now is a set of tuttle fins.

I have gotten some weight of existing boards on the market through my thread in the kiteracer section. I will work on the model this weekend to determine my values.

Its harder to add me to the model for the CoF, and then add the force of the kite as its always a variable.

[shawn13]

Heres an update on my progress. i have modeled an existing raceboard and the results show that the center of gravity is centered almost at the bottom of the board directly between the two front fins. The CoG is represented in the photos by the red X. I will design my shorter board in 3d first to determine my center of gravity is located in the same spot. Will mostlikely add resin blocks forward or aft to balance the CoG.

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[davesails7]

Will mostlikely add resin blocks forward or aft to balance the CoG.

You mean blocks to move the footstraps to different positions? If so, I think that's a good idea.

If you're talking about adding weight to change the trim of the board, don't do that.

[shawn13]

Will mostlikely add resin blocks forward or aft to balance the CoG.

You mean blocks to move the footstraps to different positions? If so, I think that's a good idea.

If you're talking about adding weight to change the trim of the board, don't do that.

Okay thanks. Will try that on the smaller design.

[Peter_Frank]

As light as possible - and I dont know why you would aim for having the COG at that point ?

Maybe because you have seen other longer boards having that ?

Think it should be really far aft, and having a shorter nose thus less swing weight is an advantage performancewise.

Do NOT put weights in the board

Peter

[BWD]

why is the board so long and nose heavy?

because you put too much weight on your front foot
and/or
because the nose rocker is not enough
and/or
because the nose is too wide to be spearing chops at high speed
and/or
because the whole board is too fat
etc,
but not because of the Cg is anywhere or nowhere.

Actually, if the board was narrower, and even longer, with 10-15cm of nose rocker, it would fly over and through waves with no problem, so length, also, is not a problem (until you need to put it on a plane).

[longwhitecloud]

most awesome idea, have been trying to get around to developing an open source design that can be measured. I reckon a single fin would be a good feature from cost point of view or maybe a retractable fin so you can go downwind suuuper fast..

[shawn13]

Update: So when i entered the blank into CAD it was smaller than I originally thought. Its 180x56x7cm. So I have modified the design to adapt to my existing blank.The new design is still 150 in length for airline travel. Also the rocker table I have is 160 and I want to vacuum in one shot on the table.

Im not sure if I can use racefins with tuttle boxes as the box will have to be cut significantly since the blank is over an inch thinner than a standard race board. I may have to move to minituttle/fcs boxes and much smaller fins. With the current configuration the CoG has move further back. It weighs 11 pounds. Thoughts?

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[davesails7]

With the current configuration the CoG has move further back. Thoughts?

Sorry I might have been confusing you. Don't worry about the CoG of the board. I was talking about on your original graphic that you would have your weight too far forward.

The CoG of you and the board together is what matters. You weigh a lot more than the board, so the CoG of the board itself doesn't matter much at all compared to where you put the footstraps.

Looks good though!

[longwhitecloud]

what airlines only allow up to 1.50?