hail arm chair engineering
give the lad some snuff.
…ambrose…
l<:}>=0<l
and hand the work off to a crafty bugga like
monsuir Genius and take credit for the product’s
quality of execution?
Cad had an archaeic meaning
and then in the early century it meant somthing else
soon it will become a personal pronounnoun
again.
caddilac dominated the auto industry
hail c a d
You got the wrong end of the stick there Ambrose, using measurements doesn’t imply that we don’t do the hard graft, sure we do. . . and let’s face it, we all use numbers.
Beautiful prose by all the bro’s.
Hey look, I rhymed but I’ll leave it there 'cause…hey…I can’t hang with Ambrose.
Numbers or sighting, CADing or carving, it’s not for me to say, but I will be making my own 11+ beast.
I’d love to log some points off Mr. Surfore’s 11-3. But, I guess that’d be stealing and what a skallywag I’d be.
quite civil of you roy.
nice to hear fom you
yes we owe a great deal
to the arabic culture for their numerals
not to mention that genius who bestowed upon us all the zero
knotted ropes only go so far .
I wil l give you that.
and without everything
we would be nothing.
…ambrose…
have a productive tomorrow
I am looking forward to friday
your side of the dateline has its merits.
not to mention you are 12 hrs? ahead of london.
I agree with Jim. If you can’t tell by looking at it, all the #'s in the world don’t mean $#!t. That table of porptional dgrees looks impressive though. I must say.
Sorry, but I don’t shape from a paint by numbers kit. After winning the United States Surfing Championships 3 times, I think by now I know the difference between a great riding board and a dog.
This is why took 3 days to loft out this Particular rocker.
At 12’ it isn’t going to be a turn on a dime design, the rocker needed to reflect this also.
As a new board, there was NO rocker, thus “numbers” to work from.
11’3" Clarks stretched out still left an apex in the bottom, it needed it’s own rocker and for what it was being designed for, it didn’t exist in my available archive of existing rocker templates.
!2’3" Clark rocker was simply hideous and 5" thick, this was for a less than 3-1/2" thick soul glider. Can a CAD program “see” what I am looking at, does it know what is expected of that board. Once the final design is completed, then put it to the machine, but the originals will all be designed by myself and if by chance they completely flail, then bad on me.
But after over 45,000 shapes, I’m begining to get a slight hint of what makes 'em work and that’s where I"m headed now
Paint by numbers. Thats a good one, to each his own. -Carl
Oh, I thought I would get on here and waste.everyones time with worthless banter.
hahaha… haha… that’s good humor.
You may have heard, but they just recently found an ancient scroll taped to a 12’ wiliwili board in a remote cave on the big isle which contained the secret formula for the perfect rocker on all boards: Find the square root of 3, multiply times pie, find a coeficient factor to invert, and slide it a “CH” forward until it works. Have you tried it?
richard
I agree with Jim. If you can’t tell by looking at it, all the #'s in the world don’t mean $#!t. That table of porptional dgrees looks impressive though. I must say.
Obviously the use of numbers and formulae does not prevent the resulting curves from being looked at, however as boards get bigger, a slight barely visible (but measurable) difference in the rate of curvature can make a big difference to the overall rocker measurements.
One of the reasons why long boards in the 12 foot range are so often under rockered is that the eyeballing it method tends to foreshorten the length of the board when viewing rocker from the nose or tail. . . . … this has the effect of drastically reducing the rate of rocker curvature because when two boards look similar in rocker when viewed from the ends, and one is much longer, the longer one winds up a lot flatter in terms of rate of rocker curvature.
In other words the visual designer tends to make a longer and shorter board (say a 9 and 12 footer) ‘look’ the same . . . which wreaks havoc with the rocker on the longer board by making it much flatter.
The reason above is why the eyeballing it method is not ideal when designing over a large range of surfboard lengths or moving into much longer boards for the first time . . . . the eye finds it much more difficult to measure changes in the rate of curvature than it does the overall ‘look’ of the rocker.
As mentioned previously, the eyeball method is best for reproducing boards of similar length and shape. . . which is how traditional boatbuilders usually operated too.
Also, there is a tendency for those who avoid measurement to imply that using measurements means that the designer can’t see the curves. . … this is obvious BS. . . . both tools can be used without contradiction.
PS Measuring rocker cfreates some surprises. . . . for example the rate of curvature in my supposedly overly rockered 12 footer is quite low. . . as the eyeball designer would discover if he were to cut the board into two 6 footers and then view the pieces from the tail !
Fortunately we can reach the same conclusion with a simple tape measure or knotted rope
Sorry, but I don’t shape from a paint by numbers kit. After winning the United States Surfing Championships 3 times, I think by now I know the difference between a great riding board and a dog.
I’m sure all the Americas cup designers are going to be mortified to learn that they ‘paint by numbers’ !
It’s not an emotional issue Jim, it’s just that there are many tools available to us, and mathematics is one of them. . . . each tool has it’s advantages and disadvantages, and one of the disadvantages of designing purely by eye is that it is difficult to extrapolate curves. . . the eye tends to flatten them.
A disadvantage of mathematics is that it isn’t much help when fairing and shaping. . . even Americas cuppers are sanded and faired by eye.
Hi Roy -
Once again, I find myself in total agreement with you… a little math combined with some eyeballing is generally a good combination.
I find that having some baseline numbers is very helpful especially when shaping a series of boards that follow any kind of progression. I don’t really trust the blank dimensions that are found in catalogs but again, use them as baselines for any rocker tweaks. Rocker always gets measured at my place before, during and after shaping. With all the new blank manufacturers and dfferent plugs out there, not to mention custom EPS blocks, it really helps me to have a frame of reference, i.e. measurements.
I also find myself laying a blank on something flat and “testing” it by pushing down on the tail. I can sometimes get my brain around a shape better by visualizing how the blank rocks. On boards with vee, it gives me a better idea of how it might bank and what part of the bottom and outline might be in contact with the wave.
Call it a crutch or whatever, but I haven’t done thousands of boards like Jim Phillips so every little bit helps.
Every time I read rational posts like these last two, I get insecure about my process. Process…huh. As if. I hotwire out my EPS with a flat deck & the bottom “rockered” only by thickness flow. When its in the bag getting skins, if it looks too curved, I put bricks on the ends. If it looks too flat, I put bricks in the middle. If I’m shaping a PU blank, I just skin the bottom & then eyeball what I’ve got and either thin from the top or the bottom on the ends until I have something that looks ok.
I’ve made around 25 boards, I guess. All but one of them surfed (and that was a meterials issue); 3 paddled like crap. I guess I could make them better, but without paying customers, I’m really just passing my free time without TV. I think of it more as sculpture than engineering. I try to visualize the board inside the foam and then take away the excess to make it appear. I’ve never actually measured rocker while shaping a board.
I measured rocker on plenty of boards I’ve bought. I guess I was just trying to set into my head some standard parameters. Like, if they all turned out to average 4.5" in the nose, I pretty much know what 4.5" looks like, and mine should look like that too. Or a little more, or a little less, depending on what I’m shooting for.
I’ll easily admit, I don’t know what lofting is. I also don’t know how to use APS3000 (what a relief it was not to have to read those threads! 
). And although I visualize sculpture, I don’t think of myself as an artist, just a utilitarian. Homo sapiens, making tools. I don’t even measure my boards until they’re done, except for blank length in the beginning, and center width so I can start & stop my spin templates. Thickness, oh, about like a cheeseburger. Double cheese for summer. 
Carl, I get orders from Merrick, Evolution, Billy Hamilton and they come with a complete rocker print out. I of course do have to plot out boards like this to build the blank and they are going on the machine, they have to be right on the numbers.
But, I do so very few off the machine boards for my orders, almost every one is a complete custom, there is no way to have all of these be off a program. I would like to do more machine boards to free me up, but custom is custom and that is what I do best
all seriousneesss aside
every body that did water time today raise your hand.
well I paddled the wailua today up the north fork
at dawn saw the foliage melt into the reflection
in the river .saw a heron saw a rainbow in a waterfall
stood kneeled sat paddled
must av been close to 5 miles
read some ov the velzy book,gettin close to the end,
you guys are all right
I on the other hand,
best fishes for sunday
smell the air
taste the wind
frequent a water venue
and say please and thank you
and phone yer mom.
…ambrose…
although some
are more right than others
they can be off roading.
to do it to the #ers
and be it wrong…sobering
do it to the eye
is an unmeasureable skill
not to be maligned
by science or conventional intelect
approaching omnicience,
be careful when you blaspheme
in the presence of wisdom and knowledge
one may risk being struck down by
the post pride fall.
john sebastian said it
what a day for a daydream
what a day for a daydreamin’ boy
what a day for a daydream
dreamin bout my bundle of joy
after the eye ball comes the feel
and that is that.
with out the feel
we will be easily replaced .
fred sabehagen…berserker series
I’ll raise my hand. No work on a 12’er yet. Been spending time with my bundle of joy, he’s 3months. When I do have a time to spare its usually a quick surf. Caught a couple on one of KeithM’s boards he was kind enough too share. Looks like there is no one right answer for my rocker question. Thanks to all for the guidance. I have some brown paper, and a pencil, and eventually I’ll have some time.