How consistent are machine shapes anyway?

General Discussion
1

I often don’t want to admit that I own a mass-produced shortboard, but it’s true. I bought a Rusty Pirannah about eight months ago, and although it was the first off-the-rack board I bought in twenty years (all the others came from local shapers, mostly Sorenson’s Aguas, Hollingsworth’s Lightning Bolts, a Phillips, a Clark, a Linden, and others), I still have to say I LOVE THAT PIRANNAH! Why, just today I took it out locally in windy, strong current conditions, and while paddling out felt like I was going to kook it all morning.

From the first wave on I knew it was going to be good. I still can’t believe how freaking fast that board is. Hey, my other boards are great, but this thing is THE magic board I always searched for. It hugs a steep wall, generates amazing speed in steep or flat conditions, and turns on a dime.

Unfortunately, the quality of construction leaves a lot to be desired. It started falling apart the minute I first rode it.

Seriously, the rails started to come undone in a couple spots (the cloth) from oversanding, I suppose, and I fixed them. The deck pressure dents more than any board I’ve seen. And I’m sure that by the end of the summer it will start to delam.

I won’t say who glassed it as that isn’t important. They normally do good work. It probably is from the machine overshaping or, as mentioned, oversanding. I doubt it is from my intense ripping. Hmmm, maybe. Nahhhh.

Anyway, to cut to the chase: If I, gulp, order another one of same dimensions, do you think it will have the same magic? I know it came off the machine, so I guess the next one would too, right?

I heard some people say that a magic board can never be duplicated exactly. What’s your opinion?

(oh, and please do not harp on me for buying a Rusty off the rack like that. It rarely happens. I spend countless dollars–ask my wife–on at least two to three local shapes every year. I swear. Just last year I had a fish (Clark) a hi-perf tri fin (Rod at Agua) and an 8,4 from local guys. I swear, so don’t give me a hard time for endulging on a Rusty. I know, it’s the brand name, and that takes away some of the soul, but I really don’t care about that).

Heck, if I cared about brand names, why would I wear a hat around that says Turtle Cove all the time? It’s a lame golf club in Georgia. Heck, I’m not even sure what brand of underwear I have on. There’s a hole in my sweats. My computer was built in a garage. The floormats in my car were aftermarket 9.99 specials. I eat at Especial Norte, not El Torito.

But wait. Oh crap, I do go to Starbucks a lot.

I’m a hopeless sellout :frowning:

2

the best surfers who ride the biggest waves have all their once proven shapes machine cut to replicate perfection.

I have been wood laminating on foam for many “pro/experienced shapers”. I am always amazed on how “off” some of the hand shaped boards are. When you start laying out the wood the imperfections of the shape really stand out. Now the same shapers machined cut blanks are always so close to perfect. Each side of the board matches the other.

I suggest reordering the magic board with a machine cut taking and extra 3/16" of the thickness throughout. Then get it sandwhiched wood laminated. Take it to the glasser and your durability will be off the chart and be very close to the same weight. It will cost you about $120-150 more, but will pay for itself in the long run.

3

Depends on what you define as accurate .0 .00 .00 .0000?

All machines are not created equally. Accuracy is totally dependant on the machines repeatability and fixturing. Also the machine set up is crucial for accuracy. You can have the same shape done by two separate machines and have two different tolerances. From my personal experiences there are only a few machines that can recreate exactly time and time again. Most machines shapes I have seen have quite abit of deviations, mostly due to slop in the fixturing and or set up. This seems to be the weak link on most machines.

I have only seen a handful of machines able to recreate accurate full rail contours, this is one of the most crucial areas in deviations. The main reason for the deviations is the technique in the way the master board is digitized. Most machines scan through incremental cross sections or slices. Which just averages out the missing data along the cross section. From my personal experience this is where most of the deviations occur. A full scan along the entire surface is the key to an accurate and true scan. This method takes much longer to digitze but in the end you get a much better surface.

Then depending on the shaper who actually finishes the board can change the shape/contours.

4

They are a lot closer than handjobs (so to speak). You might try taking it back to the shop and complain or ride it 'till it dies and take the hulk to someone who will shape you a dupe using a heavier blank and/or different glassing schedule (or both). Just know that the “magic” part might be that it is light as a feather…

5

Fairmont, If you bought the same Rusty board, you may get the same magic, maybe not. But it would probably be close. You know as well as any Swaylockian that the guy sanding a board does a little shaping of his own by sharpening an edge here, and rounding out a rail there.

Also, those shaping machines can only get the basic shape. The final sanding has to be done by human hands. Lots of room for personal interpretation.

Every “finish shaper” will vary from board to board on the same shape.

My guess is that you have a 50/50 chance. Doug

6

Most shaping machines are highly accurate. But what I think you are asking is if the duplicated board will be magic. The problem is that there are too many variables left. You’ve taken only one out by using a shaping machine. There isn’t yet a glassing machine or a sanding machine, not to mention a foam pouring machine.

7

BELIEVE IN MAJIK

ALL THE WORLD WILL BE AT YOUR DOOR TO DO YOUR BIDDING

deny magic and the world becomes a dreary void

stop at the rectory have the padre bless the board

then go to see Baron von Preisendorfer his self

tell him you wanna believe

stop at the budist temple and make an offering on the way to the synagogue,the ashram ,and the mosque

say nice things to every one you met and when the board comes dont judge it until you have ridden it for twenty hours of water time in all conditions

YOU ARE IN CHARGE OF ALL YOUR OWN MAJIK

dont debase the potential by simply spelling it like a cereal box label…

majik is a sensitive topic and must be dealt with properly…

…ambrose… rusty is the greatest Pirahana shaper the world Has ever known…bak bak BAK,he’s everywhere he’s everywhere

8
Quote:

The main reason for the deviations is the technique in the way the master board is digitized. Most machines scan through incremental cross sections or slices. Which just averages out the missing data along the cross section. From my personal experience this is where most of the deviations occur. A full scan along the entire surface is the key to an accurate and true scan. This method takes much longer to digitze but in the end you get a much better surface.

This is only a problem if it’s the plug for the finnished shape you like. The guy here already have a board that came off the machine that he likes. The deviation from one board made by the machine to another one made by the machine does not depend on how the plug was digitized, so it’s likely that the machine will produce the same board perfectly again. Secondly, as long as we’re talking digitizing… As long as the selected point are good enough to describe the actual shape and the algorithm used to ‘fill in’ missing data is up to par, the resulting digitized board are likely to actually be smoother then the plug. This may or may not be a good thing though depending on what you want. regards, Håvard

9

scanning and digitizing shouldnt be the issue …

that board should be on file , if the same machine cuts it , it will basically be the same …

but here come the maybes …

the difference between a good and a magic board come down to subtle nuances …

i once made 4 identical boards for a team guy , the eye couldnt tell the difference …

they all went really well , but 1 was magic ???

when the rejects were sold , everyone who got one claimed magic ??

a good board is only as good as the best board youve ever ridden …

i made another team guy a magic board about 4 boards back , when he rode it he said “youve really raised the bar on this one , so if every board i get from now on isnt as good or better than this one , its basically crap”…

he admited theyve all been the best yet , but still not as good as the first magic one …

ok so what does all this mean …

in both cases the shapes were identical , the only thing that changed was how the boards were structured glass and sandwich wise …

different fabrics , resins , different stringer wood , lap sizes , it all plays a role on conventional boards …

those nuances i mentioned before …

thats the magic , being able to see those little things that make the difference …

while cmp had a real valid comment about making it stronger , it also changes it …

if you have the time and resources to work out the magic by going through alot of variations of the same thing then doing the timber and then fine tuning from there is a good idea …

but if you want to get close to the current magic you have . try and repeat everything that went into that board , same shape , shaper , glasser , and so on …

another ideal situation , is find a shaper who can recognise why its magic …

all you have to do is place it in front of a shaper and ask how it will go , he should be able to look at you , then carefully measure the board , after checking the fins , foil , toe , cant and setts , rocker , all the various measurements , he should be able to tell you exactly what it does well and what it doesnt do with you on it …

you already know , if he cant tell you what you already know , then move onto the next guy …

eventually you will find someone who can recognise the magic and understand why and be able to recreate it even better to fine tune for you as an individual …

the team guy i mentioned before , because were always looking to improve , i have to try other variations beyond the shape , we already know 1 magic formula , but who says we wont find more magic in something else , if all else fails we go back to the best we had …

hope some of that makes sense …

regards

BERT

10

From my personal experience, scanning IS the main issue atleast where all the deviations are, meaning the main difference from the master plug. Believe me I have experimented with all types of methods.

FWIW, If the board came from Rusty he uses a Brazilian machine. And if the board was cut at the from the production machine they use an actual digitizer but use the section method. The Bazilian machine uses the cross section 2D method and the is not true 3D. The production machine also uses cross section method but they actually use a digitizer. The digitizer makes a much nicer surface but using the cross section it data will deviate in comparsion to actual 3D total surface scanning. This method is not accurate to the master, I know of a few that have this particular machine and all have mentioned this. What you see on the screen isn’t exactly what you get. And also makes some strange deviations.

The only way to eliminate this is to scan the entire surface.

True, board to board deviations are primarily a set up issue.

11

my guess is that the magic you feel is:

  1. the overall unique shape of the board as compared to other boards you ride

  2. the shape matches your style/ability and waves you ride

  3. new boards always ride better because they’re…well, NEW

so i think you could buy a new one and be very satisfied

here’s an option…after a few months of riding the thing and the high-fatigue materials turn that board to spongy mush…have someone router the entire deck about 1/8", press a combo layer of 2ozglass & 1/8" balsa in its place, then glass that over with one layer of 4oz s-glass with a foot patch…you may get your magic back.

12

The magic is still in it. I can’t believe how fast it is, and how responsive it is on the takeoff.

That’s the magic part: It’s ability to pick up speed very quickly, in all sub 8 foot conditions. Anything that’s really big and the board slides out. I don’t mind because it’s a small wave board.

My other shortboards are fine once they get going. In fact, one of my other high performance shortboards is much looser and better in all surf, EXCEPT the takeoff. It needs power to start it up.

The Pirannah does it.

I forgot to mention, though, that I actually had a 6,8 Pirannah. It didn’t do it for me. Then I switched to a 6,10. It FLIES out of the gate, and turns like a 6,4. Unbelievable.

Say what you want about Rusty, but he IS a great shaper.

Or, uh, his machine is a great shaper. But he did the master, so that’s good enough for me.

Someone mentioned sanding.

The board has a VERY sharp edge to it in the back. I’m sure that’s what is giving it that excellent bottom turn.

Cause it aint me.

13

If its the glassjob thats bothering you why dont you sand it down to the cloth and re-glass it on the top 3/4 of the board. It might add a pound but at 6’10 thats not that noticeable.

14

interesting…

here’s some magical ideas…

is the 6’10 wider than the 6’8?

is it flatter?

are bottom contours different?

volume?

front fin toein can have a big affect at the start too…more toein more tail lift at start…

are fin setups different?

im very curious now…

15

Hey Fairmont

After reading a lot of good reviews of the Pirranah, I checked one out in a shop. I noticed the tail was quite thick and slabby ie hard edges on top the rail, so it’s probably got good release behind the fins plus gets onto waves early courtesy of the extra thickness in the tail. Due to the wide nose and tail ahead of the fins, its got fair amount of straight rail between your feet so you get the fish style drive on take off. I’ve found with a fish type board I had, which combined low nose rocker with wide nose that I got tons of drive but I couldn’t pull up the face and hit the lip when I wanted. It had a pulled tail like the Pirranah so I could whip it around when I got up there but I had to pick my sections. Haven’t heard anyone saying this about the Pirranah so I’m guessing it has more nose rocker - Be good if you could post some rocker numbers or a picture and some info about fin template and placement.

Cheers,

Pinhead