sin9le concaves

[diggerdickson]

Just for interest sakes I put this thread in here wonderin9 where all you 9uys like to start them from the nose and finish them from the fins, how deep and why ( that really is the bi9 question, why? )
Ive already done the one on tims board from 9ut feelin9 if you know what I mean and some direction from a le9end.

[diggerdickson]

mmmmm, no thoughts here, oh well

[huie]

mmmmm, no thoughts here, oh well

hhaaaaaaa you expect these mob to know about concaves they dont even know what there fins do.

[Yuke Hunt]

mmmmm, no thoughts here, oh well

hhaaaaaaa you expect these mob to know about concaves they dont even know what there fins do.

Forget the fins ... they ... being these mob ... obviously don't even know what their there's do ... are still trying to figure out if boogie boarding is actually gay ... or not ... struggle to give out decent medical advice ... nor legal advice for that matter ... pretenders I say ... although with the sheer volume of porn generated viruses that Coops has recently hinted at ... he alone must be the master of one handed computer operation ... 99 change hands.
Oh and as for the concave ... don't go too deep ... and its preferable to put it on the bottom of the board.

[diggerdickson]

womble you crack me up Though I hear some are putting concaves in the deck now as well

I admit that I dont know that much about fins huei as I just trusted my shaper to get it right for me when I told em what I wanted. I did not grow up with fcs so I didnt experemint to much with this but now I wish I could but its a money thing for me, I loved a bit of flex i got once out of a back fin i had but hell mate. I didnt think much on fins back then.

but when it came to thrusters I knew that I loved 6 bloody deep channels. I loved em, I knew why, wasnt bugged about the downside of sloppy surf because they made up for it in so many ways. I knew which tail i loved on the boards through a bit of trials and why they worked, they gave me shuch confidence to take of deep and still make it around. Im just not good enough to make them yet, and I do mean yet huei, but I will be one day mate, its all aiming towards that I tell ya. I will have my channels back one day.

Soo what Im getting at even if shapers dont want to comment fair enough But for those surfers that ride and love their concaves I would love to hear why, do you have a way you like your concaves in your boards, or do you dont really care and just ride what you want and buy of the rackss because its easier and cheaper to buy a board made in china, lol.

Im sure there are intelligent people out there that have a idea of how they love the bottom of their boards to be and why but wether they wish to share is another thing

[robzig]

[dUg]

start 12 - 18 inches in front of typical front foot placement, 1/4" deep at deepest ( just behind front foot "sweet" spot ) point. IMHO you're not trying to take out the steepest part of the rocker, but the longest section e.g. the planing area.

[diggerdickson]

start 12 - 18 inches in front of typical front foot placement, 1/4" deep at deepest ( just behind front foot "sweet" spot ) point. IMHO you're not trying to take out the steepest part of the rocker, but the longest section e.g. the planing area.

Ive done it a bit wrong but it will be very interesting to see how it rides, yes I took out the longest section, the planing area, did it on what i thought, now to glass up, test ride, see if its wrong and if concave wrong work out how to to better on next board, test on a few cheap cheap blanks, you cant learn if you dont try and you just gotta remember your mistakes....

[Cpt.Caveman]

I always figured it was a balance of grip, buoyancy and lift with concaves right? I mean the deeper the concave, the more grip it provides, so a the placement of a deep concave will make a difference in how easily the rail or tail releases...

[mustkillmulloway]

nice post caveman

i had a magic webber ( actually i've had two best boards eva off him)

he was in a mood and made this 6'6 squash tail with a massive double concave

as only webber would do

couldn't turn it for all i was worth...but man...i never got stuck behind a section

thinking about all my magic boards....they all been heavy concaves and shared the most wonderfull rocker curve in the last two feet

the rocker between the fins is the secret i reckon...u got get that sweet

[tiger]

I generally view it as marriage of concave/rocker/planshape.

Concaves create lift and squirt. Full planshaped, low rockered boards already have a lot of inherent lift, due basically to planing area. So they need little in the way of concave.

Conversely curvy rockered, low planing area boards. Need plenty of assistance in the form of deeper concaves, to make up for the lack of inherent lift. NB this does not include big wave boards, I'm mainly talking about performance shortboards.

I'm like Robzig. Concave starts at the water entry point on the rocker and blends in and then out with it flat again behind the rear fin. If you were to measure a point between where the rocker starts and finish's, I usually have the deepest point fractionally behind halfway.

Depthwise on most boards with plenty of planing area/flatter rocker, the concave is barely there. 1-2mm is usually plenty. Where as with more performance orientated boards I'll have more like 4mm at the deepest part.

The usual advice Digger, keep it simple to start with. Most of the boards you'll be making will be of the fuller/flatter sort, so minimal concave will be appropriate. You can't make too much of a mess keeping things subtle. But if you start trying to put wild bottom contours in you can make a real mess.

[diggerdickson]

thanks tiger, I appreciate it mate

[Cpt.Caveman]

You can't make too much of a mess keeping things subtle. But if you start trying to put wild bottom contours in you can make a real mess.

That was my mistake on my first home shaped board. Deep single to double with vee... *shakes head*

[diggerdickson]

You can't make too much of a mess keeping things subtle. But if you start trying to put wild bottom contours in you can make a real mess.

That was my mistake on my first home shaped board. Deep single to double with vee... *shakes head*

[gibber]

mmmmm, no thoughts here, oh well

hhaaaaaaa you expect these mob to know about concaves they dont even know what there fins do.

cantankerous old cnut aren't ya
Why not add to the discussion with your thoughts instead of taking the holier route and imply you have more knowledge than the mere fools on here

Anyway I'm gunna have another beer

[diggerdickson]

mmmmm, no thoughts here, oh well

hhaaaaaaa you expect these mob to know about concaves they dont even know what there fins do.

cantankerous old cnut aren't ya
Why not add to the discussion with your thoughts instead of taking the holier route and imply you have more knowledge than the mere fools on here

Anyway I'm gunna have another beer

sounds like a great idea, another beer that is.

[maggot]

Wanna know about concaves n rocker, talk to Greg Webber. As far as Im concerned hes the king of curve.

[Natho]

Ok Ive got a bit of a concave question.
Im surfing a brand new board at the moment. Its a Chilli CN Curve, glassed light.
Flatter rocker with single all the way through.

I normally ride single to double with average concave up front to deeper concave between the feet just before the fins.

The Chilli seems to have a deeper concave a bit further forward on the board compared to what Im used to, towards my front foot. The concave then gets even deeper before the fins.

Im finding the board has a 'twitchy' feeling rail to rail when projecting down the line. The only time Ive felt similar is when riding rounded pins, though this board is a squash. In the past its been more the rounded pin twitch in the back end.

Ive only ridden the board a couple of times in small waves so far.

My theory is that the deeper concave (than what Im used to) towards the front foot is creating more lift in the front end. The extra lift along with the lighter board is causing the board to feel twitchy rail to rail when going down the line due to the extra lift. Also because Im surfing smaller waves Im being forced to surf the board further forward than I would like. This is adding to the forward lift in the board. At least thats my theory so far. Im sure the light blank may have something to do with it too.
I gave a mate a go who is a great surfer and is very good at picking up on technical aspects in a board. I didn't say anything to him, but his feedback on the board was exactly what i had experienced (that twitchy feeling under foot). He also rides single to double rather than deep singles.

Other than that we both really liked the board.

Has anyone else had a similar experience with singles, or have an opinion on what that rail to rail twitchy feeling may be? Just interested in opinions because Im not saying Im right and it may not be the concave but it looks like it so far.