fin placement on bodyboard?!

What works and what doesn't. Share design ideas, references and contacts for paipo board builders.
flojo
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fin placement on bodyboard?!

#1

Unread post by flojo »

ok-I know this will rile up the purists here, but as an experiment, I put a couple of soft top fins on an old bodyboard-It is a too big, too wide bodyboard that I could not keep from sliding out whenever the wave got steep. the fins made the board a lot more fun to ride but I think I could improve the placement of the fins. any suggestions on best fin placement?

thanks,
Dennis
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Re: fin placement on bodyboard?!

#2

Unread post by Nels »

I'm kind of a finless type but I didn't want to leave you hanging out there. On a Frankenstein adaptation of a chunk of Wavestorm I placed the salvaged fins roughly like a mini simmons with the tips roughly to the squared off tail. So that was a couple of inches in from the rail. Untested to this point but since it's a salvaged beast all kinds of things may be off on it. But that's how I keyed it.

I had a 54" kneeboard that I used finless as a paipo for years. It had two O'Fishel fins a but further up than what I described previously. They were great most of the time but in beach breaks, which I migrated too during that period, they frequently hung me up and got me pitched. Finless...no problem.

At this point I think progressively smaller sets of fins in the more-or-less "standard locations" would be interesting to play with. If the board is a sacrifice I'd say play with it. Hopefully photos with reports? Have fun.
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zensuni
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Re: fin placement on bodyboard?!

#3

Unread post by zensuni »

The only reason I would put fins on a bodyboard would be to use it as a kneeboard. For a classic prone use, you may just use a smaller finless bodyboard, or a paipo. Bodyboards rails are thick and sometimes hard to engage, this is where paipo boards shine, no turning issue.
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nomastomas
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Re: fin placement on bodyboard?!

#4

Unread post by nomastomas »

As for me, the only reason I would surf a finless board is if nothing else was available...surfed finless body boards for over 30yrs, beginning in the late 70s...thrill is gone. But don't let me stop anyone else from having the experience. Heck, I still body surf when all I have is my fins...

Posted on another thread, but worth repeating here...Fin set relative to outline more important than a specific measurement. Wide-point forward boards, e.g. boogie boards, have relatively straight outline (parallel rails) in the rear-half of the board, so for those boards I place the fins on the rear corners, being sure tip doesn't overhang tail block. Fins on boogie boards help with hold but make the board stiffer, less easy to turn than without fins. For fins to be truly effective, all aspects of the design, including outline curves, bottom contours, foil, etc must be taken into consideration to determine if and where fins should be placed. You can't just stick fins anywhere on any board and improve performance. Oftentimes, performance is worse due to conflicting design features. Something I had to learn the hard way...
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rodndtube
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Re: fin placement on bodyboard?!

#5

Unread post by rodndtube »

There are many drop knee enthusiasts that use a pair of relatively small skegs (fins), small in height and longer in base, with the skegs asymmetrically set to reflect inflection points. Very nice mini-skegs/sidebites. I have a pair of the VT for trials when covid-19 breaks and I can hit some real surf again. Thus far limited trials...
https://www.facebook.com/vektorsystems and http://vektorsystems.com

Regarding those large fins on the 54 inch board, yeah they do hang. For some reason on a trip to N. Oregon on a new board, for some reason I forgot to pack my sidebites but the standard 3.5 inch fins that came with the board were all I had in addition to my 4.5 inch center fin. The wave favored coming off the top with drives to the bottom, but kept hanging up. I went in and removed those monsters! That afternoon, by luck, a local surf shop just happened to have a pair of Turbo Tunnel Side Bites, grabbed them and was back in business. What a difference :)
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krusher74
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Re: fin placement on bodyboard?!

#6

Unread post by krusher74 »

flojo wrote: Thu Feb 25, 2021 1:45 pm ok-I know this will rile up the purists here, but as an experiment, I put a couple of soft top fins on an old bodyboard-It is a too big, too wide bodyboard that I could not keep from sliding out whenever the wave got steep. the fins made the board a lot more fun to ride but I think I could improve the placement of the fins. any suggestions on best fin placement?

thanks,
Dennis
It would help if you supplied a pic of where the fins are now and describe what you want to improve on, otherwise how are we to know what we are starting from.

if you the board if hard to turn and you have to move to the back of the board to make it turn they are too far back.

Every board I have ever tried with fins has caused me to move from a good trim position to further back to make a turn which is a real pain in the ass. stand up surfers have the back foot over the fins and pivots around that. on a prone board, you pivot around a point much further forward. If you look at kneeboards you will also find their fins are forward of a stand-up board position.


On a finless board if you are losing an edge you do not have enough weight on the inner rail. you should have your hip and elbow on the inner rail and be pulling up on the outer rail with your hand to stop the board from going flat on the wave face. you should not be lying in the middle of the board flat on your belly.
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