MyPaipoBoards Forums

I like the outline with WP slightly back. All the curve in the outline should help compensate for the flat-ish rocker vis-a-vis turning. Aspect ratio (L:W) looks really good. Once in a good wave, that thing should fly. Question in my mind is whether or not ultra-thin rail will hold a high-line without side-bite fins. The thin rail will shed water like crazy; great for speed but not so great for hold. Its not that the thin edge won't hold, more a question of holding the edge; any slight weight shift beach-side will release the edge (some will argue that a rider can use swim fins to help hold a prone board and rider in position on the wave. My experience is that there is a heavy drag penalty for using this technique) All in all, the beginnings of a fun experiment.

Thanks for the feedback!
My initial plan was to get fins. First I thought about using 4 little fins, with 2 symmetrical on the center and 2 asymmetrical on the outer edges. Now I'm considering only 2 larger asymmetrical fins without canter or convergence.

In the meanwhile I've added an hand grab on the nose to make it easier to control.

Use symmetrical foil if no cant or toe-in. Much better hydrodynamics. Asymmetrical foil benefits toe-in. Toe-in benefits turning. Use 0" toe + sym foil for max speed, 1/4" toe +asym foil for max turning, 1/8" toe + asym toe for in between. On quads, 1/4" toe in front and 1/8" to 0" toe on rear depending upon how close to stringer the rear fin is set. closer to stringer the less toe-in.

Also keep in mind interaction between rocker and fin toe-in. Flat rocker resists turning more than curve-y rocker. Flat rocker plus no toe-in = max speed, but very stiff handling. Lots of rocker plus lots of toe-in is very responsive, but needs to be constantly turned (up and down wave face) to maintain speed (or else will stall due too "snow plow" effect) Object is to find balance between competing design factors.

Thanks, lots of good information to process!!

I was thinking about asymmetrical fins mainly for simplicity, because I would tape them together and shape like a symmetrical, later separating them and by this way ensure they would be the same size, shape, etc (just me been lazy).

From what you've said I think that asymmetrical fins without toe in or a 1/8" toe in could be a good compromise, when considering the board has no rocker and just a nose kick (remember it comes from a skimboard).

(finless guys are chuckling to themselves...)

Funny you mention finned & finless. Below are four photos of the same board. The first two are before and the third photo is after the deck glass was stripped off and rocker was forced into the board. Why, because it nose-dived too easily. I rode it yesterday with fins, first time I've ridden a finned board for quite a while. I found it awkward. I tried a smaller set of fins to those in the photo. I might try these bigger fins. The drag feeling isn't one that appeals, so I'll either surf it with fins or add some wings and ride it finless. The 4th photo is from a trip to the US a few years ago at Spot X

To avoid too much drag, too much stability and reduce the possibility of the fins to break I'm considering something like the the FCS B5 Bonzer

If it is a true bonzer fin, it will have an angle that that may be unsuited to a standard board.

I'd still recommend trying the board without fins to see how it rides. You have a simple planning device, not an overly sophisticated one

I agree with #29. The TA Bonzer has 19deg cant built in to the base. Cant increases lift but decreases hold. Typical Bonzer set up has a 6.5” center fin to counter drift. Your challenge will be installing removable fin boxes in such a thin hull. Removable because knocking off and re-installing glass-on fins is a PITA. However you choose to attach fins, stick with tried-and-true dolphin template and vary fin depth to dial in size. Then change length of base or width of tip. You’ll learn a lot…

Sorry, maybe I was not clear. I'm not going to use FCS fins, nor I will use fin boxes.
I'm considerind something with fhis aproximate shape, like my old Atunas used to have, with a very low aspect ratio.
Usually I surf in a beach break with very irregular conditions, that breaks very near the shore, so a high chord, low span fin (like a bonzer) is less likelly to hit the ground.
Tomorrow I will start shaping the fins and will send you a picture, but today I will stick with doing nothing because Mrs. 2nd dose Pfizer is giving me headaches...

Have a nice weekend!!!

That style of fin could be ok, especially if you are riding into the shallows.

Iv'e surfed around Peniche - what are the waves like down your way?

Look to the skim, kite boarding groups for some through-board skegs/fins.

bgreen wrote: ↑Sat Jul 31, 2021 11:31 pm That style of fin could be ok, especially if you are riding into the shallows.

Iv'e surfed around Peniche - what are the waves like down your way?

With some luck they look like this... but ii's a beachbreak so it changes almost everyday.
During the winter this beach can produce some really big waves, but usualy closeouts that have claimed a few lives...

I was too looking for very small fins for my paipo/kneeboard hybrid, and went for this alternative: TMF knubster, it is supposed to be a center fin, I use it as twin fins.
Comparing to the 2 classic thruster fins I tried before (bigger), the drag is significantly reduced, but it still does the job of preventing side sliping.