Author Topic: Getting a SIMSUP  (Read 11298 times)

stoneaxe

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Re: Getting a SIMSUP
« Reply #15 on: January 25, 2013, 07:09:16 AM »
I'm jumping in too. I'm thinking the L41 S2 or 3 custom to my size and with my crappy balance and need for stability in mind. I still need to talk it out and see what dims make sense for me. I'd like to get it down to at least 8-6, thinking about 8-0 though.

When you talk it out, don't let those Cali boys shape the rails too thin or dome the deck. They have no idea what surfing in typical east coast wind blown seas are like  ;) ;D. Their victory at sea conditions, are glassy clean to us  ;D ;D ;D

I got cocky and shaped some thin railed Cali style boards. I couldn't even stand on them. Can't even give the board away here.

Back to my standard FLAT deck MEDIUM thick rails. East coast style baby  ;D

Absolutely...my South county 9'er is what I measure stability against. It makes even me look good. I really don't want to give up much stability since it's critical to my enjoyment. I also need to stress how different it is for me. What some folks think is very stable is still tippy to me.
Bob

8-4 Vec, 9-0 SouthCounty, 9-8 Starboard, 10-4 Foote Triton, 10-6 C4, 12-6 Starboard, 14-0 Vec (babysitting the 18-0 Speedboard) Ke Nalu Molokai, Ke Nalu Maliko, Ke Nalu Wiki Ke Nalu Konihi

SoCalSupper

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Re: Getting a SIMSUP
« Reply #16 on: January 25, 2013, 07:16:30 AM »
I promise... I didn't email dimensions to L41... I promise!

SL
Is that on the record! 8)
rainy day here in socal-think ill go visit Dave today....
all you guys ordering new simsups is killing me!....
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Boludo

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Re: Getting a SIMSUP
« Reply #17 on: January 25, 2013, 07:50:08 AM »
I promise... I didn't email dimensions to L41... I promise!

SL

Leper,

Let me know when you want to try out my board.  You may be a little on the heavy side for it but this board will still be easy for you to balance on.  Actually I'm a bit hesitant to letting you try it out.  Maybe if you can draft up a document signed by You and I saying that you agree to give me my board back after you demo it.  ;D

Boludo

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Re: Getting a SIMSUP
« Reply #18 on: January 25, 2013, 07:51:34 AM »
I promise... I didn't email dimensions to L41... I promise!

SL
Is that on the record! 8)
rainy day here in socal-think ill go visit Dave today....
all you guys ordering new simsups is killing me!....

Juan,  rainy days are when all the shapers really make the money.  Give me a report on how it goes with Master Dave.

14 West

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Re: Getting a SIMSUP
« Reply #19 on: January 25, 2013, 09:15:14 AM »
BTW, if you're standing with feet wider spaced than 18" you're doing that wrong too. Wide feet = unstable.

This is so true, but counter-intuitive to some of the other sports people are familiar with where the opposite is true such as snowboarding or skiing. It feels unnatural at first, but the idea is it decreases the leverage on the rails thereby not magnifying the effect of minor lapses of balance. The key is to be loose and "go with the flow", at first it will probably feel twitchy and less stable, but if you just relax and let it happen you'll stay drier!
Don't forget to bring a towel!

Strand Leper

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Re: Getting a SIMSUP
« Reply #20 on: January 25, 2013, 09:22:22 AM »
...And Kirk got back to me at 5:30 this morning.  Talk about service.  

Then I was looking at old shape files from Corran... and a cutback that he made me three years ago was basically a (too) low volume simmons inspired board... from the entry rocker, to the deep and wide vee off the tail, to the slight diamond tail... to the wide tail... from the wide nose... de ja vu!  (Adam snapped it at well over head Sunset last winter).

Fifteen e-mails back and forth later, Corran is firing up the CAD machine and the planer... we are going to flip the nose just slightly for verticality... but otherwise keep the same entry rocker.  Do it at about 98 liters.

So in addition to Kirk, Dave D, and Dave B... we are going to get Corran A's take on the SimSUP design.

Because of the flip tip and my irritating contributions (likely ignored) to the shape, I am going to either call it the TimSUP or the Strandlubber.

SUP design 2013, moving forward by looking back!

Can't wait to try your board Boludo... I will draft something up... but there will be some significant loop holes.  :)

Back to work.

SL
American Saltwater Angler Magazine's Seven Time Angler of the Year.* Founder and former CEO of "Fishstrong" an organization devoted to the fight against fishbait-hands-smell discrimination.

* subject to revocation due to a pending investigation by the FDA (fisherman drug association)

Ake G

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Re: Getting a SIMSUP
« Reply #21 on: January 25, 2013, 09:49:51 AM »
As an East Coast simsup owner I could not agree more! Because at my height/wt and skill level I wanted more than a "clean-conditions bluebird day" kind of board. My Simsup has full (but sharp) rails, a relatively flat deck and super wide n' flat square tail.


I'm jumping in too. I'm thinking the L41 S2 or 3 custom to my size and with my crappy balance and need for stability in mind. I still need to talk it out and see what dims make sense for me. I'd like to get it down to at least 8-6, thinking about 8-0 though.

When you talk it out, don't let those Cali boys shape the rails too thin or dome the deck. They have no idea what surfing in typical east coast wind blown seas are like  ;) ;D. Their victory at sea conditions, are glassy clean to us  ;D ;D ;D

I got cocky and shaped some thin railed Cali style boards. I couldn't even stand on them. Can't even give the board away here.

Back to my standard FLAT deck MEDIUM thick rails. East coast style baby  ;D

adamrod

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Re: Getting a SIMSUP
« Reply #22 on: January 25, 2013, 09:55:39 AM »
Hey DW, why doesn't a domed deck make sense for east coast?  Is it only because it raises the center of gravity?  I'd like to hear your ideas for an east coast specific simsup.

Flat decks are just more stable than domed, regardless of volume.




can someone explain to me WHY a flat deck is more stable?

Ake G

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Re: Getting a SIMSUP
« Reply #23 on: January 25, 2013, 10:19:23 AM »
I'm no board designer or shaper but generally speaking, It's about volume distribution.One aspect is that boards with flatter decks seem to have the volume spread outward more towards the rails. Thicker rails = more side to side stability. Another is that a board having a domed deck will have a higher center of gravity.

Dwight (DW)

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Re: Getting a SIMSUP
« Reply #24 on: January 25, 2013, 10:29:48 AM »

can someone explain to me WHY a flat deck is more stable?

Can't.
That's why so many people don't get it. You have to experience it.

JeanG

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Re: Getting a SIMSUP
« Reply #25 on: January 25, 2013, 10:38:57 AM »
Disclaimer: I don't know jack shit about board design.

I can offer conjecture:

-Flat surfaces are easier to balance on.

-Flat decks lower the riders' center of gravity.

As others have noted, one only really needs ~20-23" of flat surface dedicated to standing area. This leaves several inches per side which can be dedicated to tapering the flat deck down to the rail. Cardiff's 7'7 SB Pro does exactly this. I, an ultimate layman know-nothing, don't see a downside to this approach.
« Last Edit: January 25, 2013, 10:43:51 AM by JeanG »

SUPCHLU

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Re: Getting a SIMSUP
« Reply #26 on: January 25, 2013, 10:52:24 AM »
I promise... I didn't email dimensions to L41... I promise!

SL
Is that on the record! 8)
rainy day here in socal-think ill go visit Dave today....
all you guys ordering new simsups is killing me!....
No kidding!!! Just picked up my new board from Chelu just last week, ridden it four times, and now want to order one of the S3s.   :-\

Guess I've finally figured out one of the drawbacks of reading here......finding to many "I wants", with not enough "I got the cash" to satisfy all of them.  :'( :D 

tautologies

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Re: Getting a SIMSUP
« Reply #27 on: January 25, 2013, 01:18:28 PM »
can someone explain to me WHY a flat deck is more stable?

I have flat to concave deck on my kiteboard...and actually I think the hokua has a fairly flat deck in the paddle area...at first a little unusual, but feels easier to handle in a way. I think maybe your feet are calibrated for flat surface, and will maybe therefore provide better balance response between water to board input than a domed deck?
I am guessing here. No science behind it. puuuure speculation.

Funny thing..my simsup has a huge concave on the deck. I am curious how that will work. the board looks crazy and fun.

I gotta find a pad to put on the beautiful bamboo... :-(

14 West

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Re: Getting a SIMSUP
« Reply #28 on: January 25, 2013, 01:48:03 PM »
can someone explain to me WHY a flat deck is more stable?

Simple, it's all about weight distribution. A flat deck evenly distributes your weight between both feet evenly and across the bottom of your feet. A domed deck shifts that weight to the outside of your foot, where, if you read previous posts, that weight becomes more unstable. Thing of it as sliding/rolling your ankle to the outside, where do you get the "bite". Which begs the question: Would a concave deck have the opposite effect and makes things more stable?

It also raises another point - Starboard claims the flat deck increases stability at speed as it should, but the downside is that for the same reasons a domed deck is unstable standing, I believe them to be a bit more responsive while surfing. In smaller waves this is probably useful, in larger waves the added stability probably outweighs this though.
Don't forget to bring a towel!

corran

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Re: Getting a SIMSUP
« Reply #29 on: January 25, 2013, 02:10:21 PM »
Hey DW, why doesn't a domed deck make sense for east coast?  Is it only because it raises the center of gravity?  I'd like to hear your ideas for an east coast specific simsup.

Flat decks are just more stable than domed, regardless of volume.



can someone explain to me WHY a flat deck is more stable?

More volume = more stable... (in the traditional sense of course). Add volume and width and its even more stable. Instability comes from a rail diving down, the board sinking and then you loosing balance and falling off. Volume, and volume away from the center line, increases stability.

It takes 8lbs of pressure to sink one gallon of air. Lets assume for this purpose that your board is pure air (no material to make the foam as its close enough for this). If you weigh 200lbs, you need a MINIMUM of 100ltr in your board to have neutral floatation. This is just to float you with the very top of the board right at water level.

Now, stability is not the same as float, but they are related. Stability comes from the ability of the board to "push back" at you when you push down on it. at 100ltr, 50lts is on each side of the stringer. So it takes 100lbs of pressure (weight if you like) to push the right rail into the water. If you're standing centered on the board you're good. As you loose balance (lets say to the right) so you transfer more than 50% of your weight to that rail. Now you have more weight on the rail than the volume is able to push back against, and so it sinks. The more it sinks, the more you loose your balance, and the more weight you transfer onto that already sunk rail, and it sinks more... and more... until you either fall over, OR the "center" of the boards volume passes the 'tilt" point and it flips over (and then you fall).

However, its not that simple. Its not just about how much volume is on each side of the stringer. its also about how FAR it is from the stringer (moment arm), and how much of it is how far from the stringer.

If 70% of my right sides volume is within the first 6" of the board (measured away from the stringer) and only 30% is 15" from the stringer (on a 30" wide board), and I'm standing 10" away from the stringer, then my foot is already outside of the area that has the most foam/floatation. Therefore less pressure (weight) is required to sink the rail.

So... a board that has a lot of rocker, or a lot of outline curve, is going to have less volume out away from the stringer to push back at me than a board with wide ends, low rocker (low rocker engages that volume sooner as its already on the waters surface - rockered boards have a certain amount of the volume lifted out of the water and it only engages after the board starts to lean over). Boards with pinched rails and deck crown are going to have less volume to push back at you.

So... what does this mean?

A 25" wide 9' board that has wide ends and a flat deck with full rails and is 100ltr will be more stable than a 30" wide 9' board with dramatically pulled in ends and pinched rails that has 120ltrs.

But this is overly simplistic... standing height affects stability. For every 1/2" you move up, you need to add on average about 1" per side of width )this is dependent on rocker, width, outline and so on, but its about this) to have the same overall stability, so you get quickly reducing returns on increased volume from increased thickness. Also, as your board gets shorter, so you introduce a new dimension of instability  -end to end sinking which compounds the side to side instability. As you get closer to the "critical" volume for your weight (you and board combined) so reduction in length has an exponential affect on overall stability, and thus moving more volume towards the ends of the board becomes paramount to maintaining that stability.

One solution is to stand closer to the stringer. While this puts you in a position of feeling like you're always "slightly wobbly", its also harder for you to put the kind of pressure on the rails that causes them to sink, as your weight is centered.  Closer feet, kung fu style, will allow you to have much less instability as you're not pushing out on the rails. Pulled in ends, more rocker, pinched rails are all benefits of a tight standing stance as YOU loose YOUR moment-arm of pressure to push on the rails, and thus the board needs less of that moment-arm to push back.

Wide boards, wide ends, flat decks, full rails, low rocker ALL increase stability if you stand with a wide flat stance. The downside is a massive reduction in board performance. As your stance narrows, so you can quickly reduce volume, and more significantly, reduce how far that volume is located away from the central part of the board, and thus shape the board, with a view of more surfing in mind rather than paddling (stability) in mind.

Make sense?

Corran

Narrow stance lets you have a smaller, narrower more progressive shape overall.



« Last Edit: January 25, 2013, 02:56:20 PM by corran »