some basic questions about shaping my first keel fin fish

General Discussion
1

I ridden friends fishes (loved the fast glide) but never owned one. Finally picked up a Rhino Foam 6’0" kneeboard bland and started cutting foam. The blank is super thick…3 1/4" in the center and very thick around the nose and tail. I cut out my template 5’10" x 21 (8" forward of ctr), tails are 10.5" tip to tip. Thinned it down to 2 5/8", and attempted to reduce the nose rocked by mowing some foam out of the bottom.

Two basic questions came up in my mind about this boards.

I’m 150 pounds so most advised me to make a 5’5" - 5’6", but given the style these board are meant to be ridden (and how i intend to ride it…fast sweeping turns on long walls) is the extra 4" really going to matter?

After attempting to adjust the rocker flatter (something i’m definately not good at) there is still 4" or so of nose rocker although it looks to my untrained eye to be mostly in the front 18". So with that much nose rocker is the template with the 21" wide point 8" forward of center going to be non-functional. I’m worried I wont be able to paddle with my weight forward and most of all glide FAST with my weight forward with this much nose rocker. BTW, as shaped there is currently 1.5" TR.

2

FWIW, I think the matter would be with pushing water paddling and on takeoff, but more important to the ride itself, when youre railing on a long wall, with any steepness, 6 extra inches ahead of the WP is just extra weight out of the water, which would affect handling

Watch this:

http://www.allaboutsurf.com/common/qvideoView.php?bg=&mediaPath=/media/05/hydrodynamica/&wd=240&ht=195&videoName=hydrodynamica.mov&caption=Video%20courtesy%20of%20Richard%20Kenvin

3

I’m not sure what janklow is talking about, pushing water 6 inches in front of center, but 8 inches is pretty far up there. All my fishes are 3 inches in front no matter how long or wide. No theory, just application and consistency with the results. Four inches of nose rocker is a bit more than mine, too, but I don’t really measure it until the board is finished and if I’m curious. They usually turn out around 3 1/2 inches. What’s another 1/2 inch? Forget about what people think. You’ve already cut it out and started. Finish the board and ride it and report back how it rides. It’s all part of the fun. Good luck. Mike

4

I was talking about length ahead of WP and associated rocker and push… if there were room to whittle it down and still make the outline make sense. It gets confusing when youre trying to work around rocker apex, overall length, WP, and length ahead of WP in your head. I’m guessing if he were to whittle the length ahead of WP down a few ", the line behind WP would have to be adjusted now, and that’s probably problematic

I think your rule about 3" is important point, though. I always think of WP back as “wheelbase.”

5

Hi Janklow,

Your ahead of me in your thinking. My experience with rockers that push water are rockers that accelerate the first 6-8 inches. Like the thrusters that were the fad around 93-94. I’m not sure how the wp forward will affect that other than the added bouyancy in the front half. However, I don’t do this as an intellectual exercise,but just build stuff for fun and see if the board lets me surf the way I like to surf, hence my recommendation to finish the board, ride it, and report back. I don’t think 8 inches in front of center is/was that unusual for fishes and the board may very well haul ass. I bet it will!

In terms of length many recommend a fishes length should be 6-8 inches shorter than your everday short board and others have recommended no longer taller than your forehead. I found you can ride them shorter than you may think, but have built them from 5-8 to 6-6 and still got that skatey, fast, feeling. I’m 5-9 and 175lbs. Hope this helps with the board. Surfing is way better when you are riding something you made with your own hands! Mike

6

I don’t think I’m ahead of you Mike–I was just talking about the amount of foam and glass that would be out of the water during steeper wall rides and turns and cutbacks, and the amount of nose surface area that would be pushing through the water during paddle times

BTW you could just belly your nose a little, Mitchell, for the paddling part of it.

7

Thanks for the feedback guys. As you said, its partially shaped and i like the look of the outline so i’m not going to try and push the wide point back. There’s enough thickness left to try and flatten out the rocker some in the front half. Pushing water paddling and while trimmed forward was a concern.

I did put belly up in the front 8" of the nose. I’ll post back with a picture.

Also, i was planning to install futures K1 fins with just a hair of toe in…maybe 1/8" Thoughts?

8

Hi Mitchell,

If the outline and curves look good it will probably ride good. 1/8 inch on a single foiled keel is good. I usually put the rear edge at the top of the butt crack, around 6 to 6 1/2 inches and lined up with the tips, around 1 1/4 inches off the rail.

Got it Greg. Mike

9

those guys are just killing it on those twin keel fishes in that video Janklow!

get’s me excited to start (and finish) the Lis Fish project in my head…

i’ve got the template, the blank, and the ply for the fins. now alls i need is

time…

10

I’ve shaped a fair number of fish out of that blank, here’s what I do to re-foil it. The push-point or apex

of the rocker is WAY forward, so I move that back by taking foam out from the center to about one foot

back from the nose. I don’t touch the tip at all, there’s plenty of nose lift already(as you’ve discovered).

The rear half of the rocker is very flat, so when I blend the above re-foiling cuts I’m putting a little curve

into the rear. The thickness in the nose has to be removed from the deckside to avoid over-rockering the

nose.

I’ve made some good ones out of this blank for some very discriminating fish riders, but it’s a lot of work

to get the rocker and foil right. It’s in there somewhere.The foam is great, though, and the boards hold up

better than Clarks. Even with the amount I’m taking off the deck they stay nice and hard.

Keep in mind that the fish I do are not intended to be exact replicas of 1972 fish. The wide point isn’t that far

up, the rocker is flat compared to most I see, and the rails are not big and boxy. And of course I could be

totally insane.

I realize you’re too far along on this board for this to help, but maybe next time.

Mike

11

Very, very cool when the pro’s jump in. I love this place. Thanks Mike D. Mike

12

Well its mostly shaped and i’m actually pretty stoked. My first attempt at a twinnie.

5’10" x 21.25" x 2.5"

rocker is a little more than i might have wanted but that’l just make it turn real good…

The wide point really is 8" forward of mid.

Can’t wait to glass it with a nice swirl of colors…going with RR Epoxy. Thanks mike d, rooster, janklow and the rest of you for advice…it gives condfidence to the nervous.