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 Post subject: Re: Shorter Race/Freerace boards
PostPosted: Thu Aug 29, 2013 4:20 pm 
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What about something like a Slingshot T-Rex?


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 Post subject: Re: Shorter Race/Freerace boards
PostPosted: Thu Aug 29, 2013 4:22 pm 
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Slayer 54? 154x54 would seem pretty close....
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 Post subject: Re: Shorter Race/Freerace boards
PostPosted: Sat Aug 31, 2013 2:26 pm 
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Here you go: https://www.facebook.com/photo.php?fbid=681224228570103&set=pb.218708941488303.-2207520000.1377955356.&type=3&theater

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 Post subject: Re: Shorter Race/Freerace boards
PostPosted: Thu Aug 07, 2014 8:08 pm 
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So I put this on hold but will be starting to shape on my holidays in two weeks. I have come up with a new design. Its a 150cm x 58. Im aiming for a lightwind board and have chosen the length to meet the 158cm airline restriction. Any thoughts before I proceed?


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 Post subject: Re: Shorter Race/Freerace boards
PostPosted: Fri Aug 08, 2014 3:14 am 
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Maybe I'm misunderstanding, but removing the nose of the board to stop nose diving seems backwards to me. I don't think the weight of the nose is pulling it down. If you cut length from the nose, I think that will increase your chances of stuffing the nose because you won't have that volume and surface area up forward to correct the board angle when the nose goes down.

Your weight is way more significant compared to the weight of the board. By cutting the nose off you are moving the center of gravity of the board/rider combination way forward as a percentage of the length of the board.

On the 70cm wide raceboards, the trend was adding more volume in the nose. From the ones I tried, this actually made the boards ride much better in chop even though most of the time most of the board is out of the water.

As far as raceboard-like performance inwaves, I like my Space Pickle. It definitely gets some of the raceboard feel of riding the board flat, using the fins more and is surprisingly fast in flat water. I think it is the wide abrupt tail. It's sensitive to weight movement, but once you get it right it just flies. Mine doesn't have straps though, not sure how it would work with straps. Don't know if you could get your weight placement right. I keep my front foot pretty close to the rail, not on center where the straps would be.


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 Post subject: Re: Shorter Race/Freerace boards
PostPosted: Fri Aug 08, 2014 3:59 am 
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I should have been more clear. Im not so worried about the nose chop anymore as I am creating a smaller board for travel. Im hoping to focus it on light wind riding when traveling, so the chop catching the nose is not as much as the concern. Locking the fins for optimum light and upwind ability are my new targets.

Dave you mentioned about the CoG. Do you know where the CoG should be? should it be positioned between the two front fins? Maybe I should model a standard raceboard with material weights and see if I can determine its CoG. Then I can position the fins in the same relative CoG of this smaller concept, therefore keeping the fin characteristics ever with a shortened length. First i will have to find a course board to weight as well as each fin, unless someone here can provide me this info please :thumb: ??

Do you think this concept with work?


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 Post subject: Re: Shorter Race/Freerace boards
PostPosted: Fri Aug 08, 2014 4:54 am 
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Makes sense. Sounds like a fun project. It would be cool if you can get it to work.

The weight placement of the rider is much more important than the center of gravity of the board itself because you weigh so muc more than the board. I wouldn't worry about the CoG of the board itself.

On planing boats you want the center of gravity about 35-40% of the chine length forward of the transom. Too far forward or aft of that and you get problems.

On the raceboard you have the added complication of balancing the sideways force of the footstraps around the fins. Trying to balance the transverse force on the fins and the weight placement on the board seems like it gets really complicated and small changes can make the whole thing not work.

Looking at your drawing above, it seems like there might be a problem when you go to head the board downwind. You have to put pressure on the front foot to head the board downwind, but I think this would also put the nose down too much. I don't know if you can keep enough sideways force on the front foot while not putting your weight too far forward.


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 Post subject: Re: Shorter Race/Freerace boards
PostPosted: Fri Aug 08, 2014 5:59 am 
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Just get a vangaurd.


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 Post subject: Re: Shorter Race/Freerace boards
PostPosted: Fri Aug 08, 2014 11:16 am 
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Shawn, have you been thinking about a hydrofoilboard instead ?

You say it should be for lightwind, and pack down small for travel.

A hydrofoil needs a much smaller board (a TT could be used) than the one you are about to make, and it rides in less wind, and packs down really small.
You can also dismiss at least one kite, the biggest one(s), so even easier to travel and pack without kites over 12m2.

So another solution that could get you to your target, and much smaller when travelling :naughty:

8) Peter


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 Post subject: Re: Shorter Race/Freerace boards
PostPosted: Fri Aug 08, 2014 1:25 pm 
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Buy one of these and cut the nose back?

Its 160 by 65 cm.

http://www.vimeo.com/90218345


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