Author Topic: The fun of unlimited boards  (Read 47834 times)

SUPflorida

  • Peahi Status
  • *****
  • Posts: 720
    • View Profile
    • Email
Re: The fun of unlimited boards
« Reply #150 on: June 11, 2016, 02:25:03 PM »
Thanks PonoBill...I totally see why your speed board responds so well to candelivering the tail above the surface.

It will be interesting to see if the route Starboard [Allstar] and Infinity [Black Fish] is taking (with deep concaves all the way out the back of a wide tail) proves as effective as more conventional drag reduction designs. Will it give the pur-ported dynamically lift to the tail? Will it reduce drag while still giving the stability of the wide tail? It may reduce drag when going full out at "Connor pace"...what about for the those that can't keep that pace up for an entire race? Does that deep concave actually create drag when not pushed above a certain minimum speed?

Since I asked the question I found a couple pictures of two of Danny Ching's unlimited boards. One had a rounded/rounded pin and the other had a square tail. In agreement with your statement about the wide tail and moving forward to incourage clean release...it hard to say for sure...but the board with the square tail appeared to have its wide point farther forward than the one with the rounded pin.

PonoBill

  • Cortez Bank Status
  • *****
  • Posts: 25864
    • View Profile
Re: The fun of unlimited boards
« Reply #151 on: June 11, 2016, 02:43:46 PM »
Here's a twofer, the tail of the Speedboard 18 and the deep duct I cut into it. The idea is to make the board finless, maintaining direction by stalling the water in the deep slot. I didn't deface a good board, this is the one that UPS freight broke in half.



I did this back in June of 2014, haven't gotten around to getting the bugs out of it. One bug is that it won't turn. Another is that it leaks.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

SUPflorida

  • Peahi Status
  • *****
  • Posts: 720
    • View Profile
    • Email
Re: The fun of unlimited boards
« Reply #152 on: June 11, 2016, 03:45:01 PM »
Here's a twofer, the tail of the Speedboard 18 and the deep duct I cut into it. The idea is to make the board finless, maintaining direction by stalling the water in the deep slot. I didn't deface a good board, this is the one that UPS freight broke in half.



I did this back in June of 2014, haven't gotten around to getting the bugs out of it. One bug is that it won't turn. Another is that it leaks.

Thanks for the look at your speed board and the mods. Like your sense of adventure. Can't wait to hear how it goes when you get all the bugs worked out.
Remember you talking about this quite awhile ago. Nice to get a look at the photo.
You were way ahead of the curve.

The difference between your concave and the Allstar that jumps out to me right away is your concave appears much deeper and gets progressively wider as it moves aft.

The Allstar appears to transitions gradually from convex to flat, to shallow concave, to deeper concave...but never it seems much more than 5/8" to 3/4"of an inch or so deep...even at the tail. It also follows more parallel to the rail line, rather from a point forward to wide point aft in a straight line.

I have not seen a All Star up close and personal. It would be interesting to plot the area of the concave from its most forward onset, to the tail( at 6" increments along the length). It looks like the width/depth of the concave in the back half of the board may be close to constant. That is...towards the midpoint (along the length) the center concave is wider and shallower...at the tail its narrow and deeper. Not sure if it stays constant or if the area is constricted to accelerate the water out the tail...or goes in the opposite direction and gets progressively bigger.

PonoBill

  • Cortez Bank Status
  • *****
  • Posts: 25864
    • View Profile
Re: The fun of unlimited boards
« Reply #153 on: June 11, 2016, 09:19:56 PM »
Trying to do two different things. The tip of the channel on my board will have a flat NACA duct to increase pressure in the tip of the channel. That stalls the water and shears it from the general flow. At least it does in my head. the widening channel keeps the water stalled, holding it's velocity lower than the water flowing over the rest of the hull. The idea is to have stability without a fin, with minimal drag.  Works on the model, not so sure about real size. I think the aim of the starboard Concave bottom is to increase velocity in the tail. Maybe they're looking for lift. Not sure, it would seem to be a lot of drag, but low velocities in water are tricky buggahs.
« Last Edit: June 11, 2016, 09:22:55 PM by PonoBill »
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

PaddleSpot

  • Rincon Status
  • ***
  • Posts: 116
    • View Profile
    • PaddleSpot.net
    • Email
Re: The fun of unlimited boards
« Reply #154 on: June 26, 2016, 10:49:38 PM »
Who said that a rounded flatwater board can't downwind  ;)


First test yesterday. This board just flies !


 
Olivier Drut
PaddleSpot.net  - Find your next SUP spot

PonoBill

  • Cortez Bank Status
  • *****
  • Posts: 25864
    • View Profile
Re: The fun of unlimited boards
« Reply #155 on: June 27, 2016, 12:12:43 AM »
That acts like the Penetrator 572. Once you get it in a bump it won't stop. Even if you run out of water.  Thats a pretty thing.

Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

PaddleSpot

  • Rincon Status
  • ***
  • Posts: 116
    • View Profile
    • PaddleSpot.net
    • Email
Re: The fun of unlimited boards
« Reply #156 on: June 27, 2016, 12:15:18 AM »
Once you get it in a bump it won't stop. Even if you run out of water.   

Perfect description PonoBill  :)

Olivier Drut
PaddleSpot.net  - Find your next SUP spot

PaddleSpot

  • Rincon Status
  • ***
  • Posts: 116
    • View Profile
    • PaddleSpot.net
    • Email
Re: The fun of unlimited boards
« Reply #157 on: June 27, 2016, 04:16:40 AM »
I LOVE you !

Olivier Drut
PaddleSpot.net  - Find your next SUP spot

Pierre

  • Sunset Status
  • ****
  • Posts: 300
    • View Profile
    • Email
Re: The fun of unlimited boards
« Reply #158 on: June 27, 2016, 05:58:07 AM »
Modern/Classic  Yacht style...
\HF/- Hi-Fun Hydroworks / custom boards,BZH, since 1982  /  *Link Removed*

PaddleSpot

  • Rincon Status
  • ***
  • Posts: 116
    • View Profile
    • PaddleSpot.net
    • Email
Re: The fun of unlimited boards
« Reply #159 on: June 27, 2016, 06:30:29 AM »
I like the carbon fiber/oak wood mix :-)
Olivier Drut
PaddleSpot.net  - Find your next SUP spot

TallDude

  • Cortez Bank Status
  • *****
  • Posts: 5714
  • Capistrano Beach
    • View Profile
    • Email
Re: The fun of unlimited boards
« Reply #160 on: June 27, 2016, 08:12:58 AM »
Beautiful board. With the rounded bottom you have to do a little more feathering and bracing with the paddle, but the speed is worth it  :)
It's not overhead to me!
8'8" L-41 ST and a whole pile of boards I rarely use.

SUPflorida

  • Peahi Status
  • *****
  • Posts: 720
    • View Profile
    • Email
Re: The fun of unlimited boards
« Reply #161 on: June 27, 2016, 08:35:32 AM »
Beautiful board. With the rounded bottom you have to do a little more feathering and bracing with the paddle, but the speed is worth it  :)

I agree it's a beautiful board...very "classic" in appearance... but as to the "little more feathering and bracing" description... "Exhausting"
is more the word that came to my mind...lol

PaddleSpot

  • Rincon Status
  • ***
  • Posts: 116
    • View Profile
    • PaddleSpot.net
    • Email
Re: The fun of unlimited boards
« Reply #162 on: June 27, 2016, 09:03:08 AM »
Not so exhausting actually. That was my first test, and a 19 km downwind :)

I need to learn how to use the paddle as a canoe outrigger float, and always have my weight on the right leg...

And I'm pretty sure I can paddle 60 miles per day on flat water with this board, effortless.
Olivier Drut
PaddleSpot.net  - Find your next SUP spot

PonoBill

  • Cortez Bank Status
  • *****
  • Posts: 25864
    • View Profile
Re: The fun of unlimited boards
« Reply #163 on: June 27, 2016, 10:24:55 AM »
Beautiful. Careful with that deck though, it's gonna get mighty hot in the sun. I carry my Speedboard bottom down because it's all carbon. It can get so hot otherwise that it burns skin.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

PaddleSpot

  • Rincon Status
  • ***
  • Posts: 116
    • View Profile
    • PaddleSpot.net
    • Email
Re: The fun of unlimited boards
« Reply #164 on: September 25, 2016, 12:48:43 PM »
If the small "ventrical" fin is helpful in some conditions and a liability in others.. a minimal size retractable dagger or centerboard could be the answer.  But much smaller than that show in paddlespots computer rendering (where the daggerboard appears to have twice the area of the fin).

Definitely, SUPflorida. The board is ready, tests will begin this week :) 

Olivier Drut
PaddleSpot.net  - Find your next SUP spot

 


SimplePortal 2.3.7 © 2008-2024, SimplePortal