Rocker measurements! Any ideas?

Hey everyone! Hows it going?

I’m currently drawing a shortboard for small waves, something in between what would be a CI Sampler and a CI Neckbeard.

It has a wide tail, but a performance shortboard outline.

I’m not sure what rocker dimensions i should use to make it work in small/mid wave conditions (mostly small). I usually like to ride boards with low rocker in these types of conditions, last board i shaped was a twin fin fish, with 1 1/2" tail rocker, and 3 13/16" nose rocker. Worked very well! But since its a twinny and has more volume and a retro shape to it, i pulled the rocker down quite a bit to these dimensions.

What i’m not sure of, is which dims i should use on this next project. Since it has this performance spring to it, i was thinking of putting some more in. Im currently at a 1 5/8" tail rocker, and a 4 1/8" nose rocker. What do you guys think? should i lower it even more, is it fine or should i pull it up a bit?

Just so you guys know, im aiming for something like the neckbeard in terms of functionallity (if you guys have the rocker dimensions on this one it would help alot!).

I’m 5’10", and weight about 140lbs, My normal performance shortboard has 23.8L of volume and rides insane.

Dimensions on my project: 5’5" x 18 3/4" x 2 3/16" (around 24.3L). Here is a picture:

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Thanks! Stoked to hear what you guys think about it!

Was thinking maybe, pull it up a biton the nose, like 4 3/8". What do you guys think?

What kind of waves?  keep the nose rocker fairly flat, and kick the tail if its a mush grovler, maybe point fins a bit more at nose.   If the waves are going to be steep, i’d add nose and tail rocker and straighten the fins.

Rockery boards in steep waves with straighter fins turn more on rail line. Mushy waves that need a more skateboard feel will be flatter, but fins with a tad mo toe n cant.

WTF is a neckbeard?

 

5-10 140 lbs…I need to buy you a hamburger. A 5-5 board would float my old arse up to my neckbeard.

Hey, its gonna be for mushy waves! should i change the rocker dims? What would you do?

about the neckbeard hahah, its a channel islands surfboard model, check it out!

So were you planning on having this board CNC’ed at your local cutting house or do you intend to hand shape.  If your current board “rides insane” ; why a new board?  Or if a new board?  Why not base it on that board?

Yes, im gonna have it CNC’ed, and ill finish the shape. Im making it for small/mushy waves, thats why! The other board works better in other conditions, and i can’t really base this one on it because its suposed to work differently.

Thanks for the reply btw!

I would pay closer attention to the rocker of the board you like (I’m familiar with the NB, a good bud used to have one & it was great for him in small, mushy waves), and the flow of the rocker, not just the totals at tail & nose.

I say that because some CI rockers are more original and less like stock rockers in blanks than boards that seem a lot more adventurous. I use a rocker I lifted from a CI design for most of my small wave short boards, including eggs, Simmons variants, you name it. The original CI board has a magical entry, that “just-put-your-chest-down-and-you’re-in” feeling, even when you think you’re just barely going to miss the wave. And its rocker is far more unique and different from any stock rockers in the blanks I use for short boards than even shapers like, say, Tomo.

I copied a Tomo Sci-Fi recently, and I found Tomo’s rocker to be surprisingly conventional, especially compared to the CI rocker I mentioned. The Tomo rocker stick I made was very much in line with the stock rocker on my favorite stock blank for grovellers, it just had different amounts of rocker (from the blank’s rocker) rather than a whole different curve. I have to do a lot more work to put the CI rocker in than I did for the Sci Fi copy. Anyway, the message is that when you actually get down and measure a rocker in detail, it often isn’t as conventional or unusual as you might expect and, if you put a random rocker on a board meant to be a copy, it might turn out great but it probably won’t ride like the original.

Related note: I have a good friend (180 lbs, advanced) that absolutely killed it in tiny waves on a Neckbeard – it was amazing how maneuverable that board was in the tiniest of waves. Very cool design. But I saw one recently (smaller rider, custom shaped by CI), in the last week or so, and took a quick look at the bottom, and nothing in particular that I could see was the secret by itself.

Gyah…it might have been the Fishcuit that was so good in tiny waves – I think it was. But he had a Neckbeard, too, before that. They were both GREAT for him.

It’s good to see you focusing on rocker.  See if you can lay a straight edge from rail to rail across the bottom as well.  Al Merrick has been playing with some impressive concaves/dual concaves/‘triple’ concaves for years.  The ‘triple’ concave (not what he calls it) is dual concaves within a single deeper concave.

It is my understanding that all of CI’s rockers are custom and secret to the point that if they screw one up on the machine, the blank is destroyed in such a way that it cannot be plucked out of the dumpster and copied.  If you borrow a friends CI or buy one and copy it you may or may not be able to duplicate it.  The reason being that a blank is ordered by them custom and then the Rocker is further adjusted via CNC.

take the rocker of the board you like for good waves and like resinhead said flatten nose and slightly tail. it’s a good way to go except for powerfull backfoot surfer that need flat tail rocker in mushy waves.

In this world , we can copy anything , ask the Chinese , a surfboard would not be much of a challenge .

Nice! Thanks for the reply!

I’ll keep it in mind, i haven’t shaped many boards either, so i gotta learn by doing right?

Cheers!

Yeah! I’ll do something like that!

Cheers!

Yeah, at the point of being able to execute a board that most lifelong surfers would say “looks good” (smooth outlines, not wavy/uneven + clean rails, not overly boxy for the design, divoted, bulgy in places, sensible foil to design & rider’s bodytype, etc.) to copy a CI rocker shouldn’t be that hard. It’s just a lot more work than eyeballing a rocker that’s closer to the rocker in the blank.

I used to use a tool I made (based on posts I found here) to measure & make rocker sticks but now i just manually measure with a straight metal bar, off the highest point at the midpoint (whether that point’s on the stringer, rail or planing surface) and make a rocker stick based on that; then the bottom goes in off of the skinned blank made from that stick.  If the original design has a concave at the midpoint, i make a fulcrum patch with tape so that the bottom of the rocker stick at the midpoint is on the same plane as the high point of the bottom at the midpoint.

If you are CAD designing, then take out any centre control point and let the curve flow from nose to tail control points and adjust to hit your numbers. You’ll get a beautiful smooth curve. You can put the centre control point back when you’re done but don’t dick with the endpoints after that or you’ll get wobbles in your curve.

I hope I’m not beating a dead horse with this… to really assess the rocker in any board you would be well advised to do more than follow the stringer.  A rocker stick is a great start but with concaves, vee, etc you’ve got way more to deal with than a basic side profile and end points.