Gentlemen - I want to discuss ‘modern’, and also good solid functional older ‘BOTTOM CONTOURS’ for psb’s, short boards etc… Long board’s ok to! Tell us about your rides! Were you getting pummeled, were you tear n it up etc… etc…alright man! Let’s get on with this !!
Discussion might cover setups, feedback data, and theory…
I’ll start w my modz:
A few day’s ago while shaping, I wanted to attempt a single to double concave. But I stopped because I didn’t want to ruin my good rocker I have… So I went with a concave vee ! It was an enlightening experience also. I couldn’t figure what tools to use to do the job… then a flash of insight came into my head! I already carved in a vee in 1/3 from tips there in the tail… then I just grabbed my surform, and quikly scrubbed vigorously a line right between my v from near tips to 1/3 up from tips…I didnt go very deep. Just a subtle dip… then I used a flexible gritty sanding,sponge I bent to fit the concave…and I scrubbed up and down the length of it all… then cross hatched sanding to bowl it out sum… gentle bowl n at end! HOLY TOLEDO! It came out sweet. Tell us all about your favorite bottom shape on psb/ short board! Make friends -even if we have different approach. Let’s just learn and grow as a ‘backyarder’, garage pro, or pro! Join in and build! We respect you - no matter how you do it.
Folk’s - I decided on mostly a ‘Flat bottom’ bcuz a surfing buddy thinks a lot of bottoms are mostly gimmicks… I kinda agree. Do concaves really make a board faster?? I didn’t notice it. It might loosen it up, or give more control… FYI -the single concave I tried was loose in sum med size surf.anyway, I’ve
heard they’re supposed to be livelier in small surf to, but this one wasn’t. Then a guy at the beach wanted to try my fish board-so I got to try a single to double concave! It seemed more lively then the single? Maybe it was just a wierd board.
Then I owned a dead flat board - a 6’10" -that blazed down the line in blinding speed! So what’s faster? flat or concaves? I’m a bit lost on it all. I heard concaves were faster? I’m shaking my head on this one?
I also tried a channel bottom ( two per side in tail), it felt real fast and maneuverable. Just wondering why they never caught on.
i have two identical boards from my shaper, one is slight single with tiny v behind fins, other is single to double with v, Th slight single i ride when the point at the end of my street is lining up and working because it feels driveyer and can turn harder off the bottom, the other with single to double i ride in average surf coz its abit looser in choppy weaker waves, i have ridden it in good barreling waves aswell though and it went just fine. I like the feel of light single though mostly. Both boards have same fin set up aswell.
Thank you for sharing Finsout !
Yeah, I haven’t had much time e concaves yet, but it sounds like my exp was similar… but the single to double board I tried had a pretty extreme vee. Not sure if that made it real loose? I suppose for small waves a single to double concave would be good. I was thinking about doing a single to double, but being I never did a concave before, I
Just did double concave through the tail.it looks really nice though ! I dished out the concaves in the spine in the vee, and it fades nicely into a flat bottom… I’m hopeful it’s going to be livelier then a standard vee? hope your builds go well with those cool concaves!
My concave bottoms get up to speed quicker, but when it’s bumpy I prefer the flat bottoms* because they seem less affected by chop.
both types have spiral vee tails (twin concs inside vee between the fins) to keep em loose. With the concave bottom the vee is within the concave so the stringer is higher than the rails. With the flat bottom the vee is lower than the rail. Only 1/8"-1/4" difference stringer to rail either way, and some of that gets eaten up by laps.
The spine on my vee is probably ‘med’, and I put a noticeable dip between my flat to concave vee. Again, my concave is not deep, but has a noticeable dip between vee.I’m glad to hear the doubles loosen it up tho! The plan is to surf this in most average conditions… And it could even mean four +.thank you for your point 02! And good luck on your board’s !
Well, my vee looks a little lower than my rails… crossing my fingers.
Anyway, I heard the doubles on seventies era single fins were longer -from wide point to tail… my geuss is, the doubles now are setup closer to the tail? Anyone?
just finished the ambrose travel twin blank…it’s 7-2 x 22 x 17n x 15t x 3…vee tail /w slight double barrel concave…if i get ahold of a camera i submit pics…came out even better than planned…oh ya…a single fin box only(at this point anyway)…i guess the first paddle out with it will be at hobie’s paddleout…btw…i made the fin for it too!!!
The two boards I surf most often are flat bottoms. I don’t have any issues with them, and I’d imagine a flat bottom in the middle and front lets it slide around the way I like it to. Maybe one of them could benefit from a double at the tail end through the fins, which gives me an excuse to shape another one…
Yup. The flat bottom seems to handle chop ok as -cleanlines points out…
Dunno, but I just want something free and fast. I was going to do a single concave to double, but don’t want to ruin my nice rocker curves - reason I did doubles.
Here’s a photo of MY CONCAVE OR SPIRAL VEE. Look closely you can see the dual concaves etc…side rails on flats there’s tucked under edges you can kinda see…
thanks -John! Dunno, but one morning I just went full bore w the surform and that nice rubber block you donated! Anyway, I am thinking about trying another flat to double on something else. Shaping it was a very rewarding feeling. I learned tons about blending a concave on this board guy’s. Now to get it glassed w mango lime green n a blend w aqua blue green swirl job! :))
