Fish Question (bottom contours)

[ks77]

I'm starting to think about getting a new fish and have noticed that Michael Miller's fish has a deep single concave running through the fins and tail. While many other shapers are making a fish with a more subtle double concave with slight vee through the fin area and tail (Hanel, Stamps).

I'm curious for someone to explain how the two different approaches will affect how the board surfs and feels (turning, speed, forgiveness, drive, more flowy vs more vertical capable, etc.). I don't know... if you've had the opportunity to surf both, what have you experienced the differences to be?

Also, in case it matters, I'm specifically wondering about a smaller sized fish (say 5'8 to 6'2) as opposed to a long fish.

 

[strez]

I had two SD fish and both had single concave throughout. CC Keel and Mabile DT quad. CC concave was deeper. Awesome boards both: so fast but had grip to turn hard.

 

[CantDecide]

That's a traditional SD fish. Likely has a 12" tail block. You can combine a bunch of different stuff (tail block size, rails, bottom contours, etc.) but (my understanding) of the traditional SD fish is 12" tail block and single concave through the fins with keels (not twins/high aspect). Fast with the single concave.

MM can mix and match stuff if you ask him. He just shaped me an 8' fish with an 11" tail block and the single to double concave of an egg with keels. I call it a "Frankenfish" (part long fish, part nozzle, part swish, part FS/Drifter). We will see how it goes. We both think it should work pretty well.

But you are right, different shapers shape different fishes. I believe Steve Brom has a single to double concave and those awesome Beatty twin keels which he sets farther up the board than a traditional SD keel fish would put the fins. HIs fishes have always intrigued me, especially the longer ones in the mid-7' range.

So, welcome to the rabbit hole!

 

[strez]

Yup, the tails were 12-ish. Mabile was only slightly narrower.

 

[Planktom]

I recall some Larmos being rolled vee entry to flat exit, but the single concave, just to inside of the fins and not to the edge, seems to be the SD norm (he says, from a couple thousand miles away lol)

 

[jory]

I recall some Larmos being rolled vee entry to flat exit, but the single concave, just to inside of the fins and not to the edge, seems to be the SD norm (he says, from a couple thousand miles away lol)

yeah my larmo classic keel is roll to vee to flat. Its really smooth to surf but not amazing at generating speed cos there's no concave

 

[Chilly Willy]

I've got a Larmo twin keel that is flat as can be. It might be slightly rolly up front but otherwise it's mostly flat. It's super fast. I haven't ridden anything with concave to compare it to, so this doesn't answer the original question at all. I often hear those boards described as "flowy", "not snappy", and not really being a vertical kind of board, all of which is probably generally accurate. I thought that twinzers were developed as a way to get more snap/vertical, so maybe the bottom contours are related to more efficient water direction in relation to those fins.

 

[NCJohn]

There are so many different opinions out there on concaves and all the other bottom contours. Hopefully some of the shapers here will respond. I wonder, because I know nothing about kneeboarding and the designs of those boards, if the deep single that seems to be the norm with the Skip and lis inspired shapers stems from the kneeboards that they evolved from.

In my experience, no matter the bottom type (and the rails and other design factors impact this too) subtle is better no matter what you go with. I have a few Fish from the San diego school and they work well with a deep single concave in those clean, walled up California reef breaks where they originated. I don't find them a lot faster or slower than my mabile which is slightly rolled to edit: spiral vee all the way out the back but they do encourage long smooth drawn out turns which I really like. The mabile can do that too but with the vee in the back of the board tighter turns are also possible and I surf it a lot more in the beach breaks here in southeastern nc which tend to section a lot more and not be as clean.

The only real issue I've had with deep single concaves is going too long and then they get sort of tracky but this again is my experience and any number of other factors could have contributed to this feeling.

 

[MASErides]

Pretty sure my Burch squit is belly to deep single concave all the way to the tail. I feel it’s not the greatest paddler but once you’re up and running it’s fast and agile!

 

[NCJohn]

Pretty sure my Burch squit is belly to deep single concave all the way to the tail. I feel it’s not the greatest paddler but once you’re up and running it’s fast and agile!

I just put a straight edge to the bottom of my Burch and it's exactly the same. By far the most single concave of any board I've owned or surfed. It's a 5'8 and I'm a bigger guy so its easy to overpower and make it turn.