I am going to build a Calif. style big wave longboard (as opposed to a full on island style gun).
I had a Stewart Gun Log a few years back and I didn’t keep the dimensions off of it (other than the 9’ 10" length) and I’d like to build a board similar to it or to a Brewer big hybrid. If anyone has a Yater Calif semi-gun, a Brewer big hybrid, a Stewart Gun log or similar board in the 9’ 10" to 10’ 0" range, please send me a note with the nose, width, tail and wide point placement off of it. A photo would be very helpful as well.
One of my all time favorite utility longboards is a Mike Eaton 9'7" X 23" X 16 1/2" (N) X 13 1/4" (T). The widepoint is 7" ahead of center and the square tail is 5" wide. It has a long panel vee that extends right off the tail. 2+1 fin lay out with sidebites 14" up and center box 6" up from tail.
The forward section of the bottom has a mild belly, not a lot of nose rocker and the board really catches waves easily.
I've ridden it with a 4 3/4" center fin in small waves and with an 8" center fin up to DOH+. With those two adjustable center fins the board has a great range and IMO would be an ideal travel board for someone who likes bigger boards.
If I planned to ride it much past DOH I'd likely get one with multiple stringers and add a little rail bulk. Mine has a number of stress cracks.
Here's a plan for you. I've built a few. It fits in the hook on large waves and paddles out the back when a macking set comes in that can clean your clock. This gun is a no brainer:
Thanks for the info. The dimensions were very useful. The nose dimensions of the eaton and the width are what I had in mind. I was leaning towards putting the wide point between 2 and 4 inches ahead of center. I am a bit surprised at the 7 inch ahead of center placement, but I’ll sketch the templates at 2 in., 4 in., and 6 in. ahead of center and see how they look before I actually cut the blank. I will put the thickness at 3 1/2 for plenty of paddle power. I think I’ll use the same bottom template that I have on the 10’ 0’’ that I have now and the same contours, single concave in front feeding into a double concave ahead of the fins and flat (no concaves behind the fins)
The blank has a t-band stringer in it already (total width of the t-band is 3/4 inch). I plan to use double 6 on the deck and 6/4 on the bottom. Right now I am leaning toward building another quad. My 8’ 10’’ versions worked very well up to DOH.
Hey Surfding. It looks like the final rocker measurement comes out at 4.25". Difficult to see on screenshot. Is that a pretty typical tail rocker for a 9’ + gun? Or is extreme or conservative?
The rocker is from an actual scan. People get throw off a bit by the numbers of a scan.
Remember when a board is cut the nose and tail are level to each other in the machine position.
It would be like taking the board and laying it bottom side up and throwing a level straight edge the length of the board then measure from the surface to the stick for your numbers from the nose and tail.
I use to have a caculation between Shapers Rocker and MATH LOGIC. The last 4 years I have been using Math Logic. I will break it out and post the formula.
As far as the gun rocker. I works unreal in big moving waters. It's nice to fit in the contour of the wave. However that just my option!
Thanks for the advice, recommendations and suggestions.
The final dimensions are:
Len = 9’ 10 3/4"
Nose = 15 1/4’
Width = 22 7/8" and placed 2 1/2" ahead of center
Tail = 14 1/2 with a diamond tail
Bottom contours will be a little bit of roll (belly) in the nose leading into a single concave with a slight flattening of the concave as it reaches the midsection of the board. That will lead into a double concave feeding into the fins with no concave (meaning flat) behind the fins to tail.
The nose will be foiled out and have a bit more rocker than my current 10’ 0". The tail will have a bit of extra kick as well.
Fin configuration will be a twinzer setup.
I’ll post pictures when it comes back from the glassing shop.
FWIW rocker numbers in the diagram look like they are referenced to a 'zero' placement at 5'10"(?)
Assuming most boards are measured from a 'zero' placement at center, the computer diagram makes it hard to compare... I.E. the rocker baseline (zero point) in the diagram is moved forward by 11" if my math is correct. (1/2 of 9'10" = 4'11" +11" = 5'10")
By standard(?) measurement method using a straight edge at center, the tail rocker would actually measure out to be less and nose rocker greater than what appears in the diagram.
I'm not saying the diagram is "wrong" (it's what the machine requires), just that a standardized method for rocker measurement is mandatory if any meaningful comparisons are to be made between boards. 4"+ of tail rocker for that type of board is actually quite a bit by my usual method of measurement. A boosted tail rocker will fit a steeper wave better, just don't try to replicate those numbers without knowing how they were determined.
A book on surfboard design and construction by James Kinstle references rocker zero point from the very end of the tail... again, no meaningful comparisons can be made to other methods...either zero at center point, or as shown in diagram.
Bottom line... make no assumptions based on raw rocker numbers without a standardized reference point.
John it can be confusing for many people this thing about ROCKER. When I got my machine and CAD programs 4 years ago I was so lost.
Take for example a standard shortboard with a rocker profile express from a scan as Nose Rocker = 4.15 / Tail Rocker 3.98". Whereas on shaping racks with the board balanced you may have values of 5.25" Nose Rocker / 2.125 Tail Rocker.
I still pull out my rocker stick from time to time so that I stay calibrated to my machine and CAD programs. I use both methods and don't have a problem with it. However try and explain it to a guy who has been shaping for 30 years with a Skil 100. Not fun so I still use the old rocker Stick. There is a rocker function in the Shape 3D program however you have to rock the board manually in the program. I would like to see a toggle buttom that would automatically make the translation from the Z axis postion to Shapers Math. This feature would help more shapers understand the program. In the meantime only a handful of guys really know how to use it. Having said all that just use a rocker stick and forget about the way CAD logic works.
I get it now. I like the idea of being able to tilt the reference plane on the computer to arrive at a zero center point. Previous posts by guys like Lee Vanderhurst and Bill Barnfield explain the center point method better than I.
FWIW, the board nor the straight edge have to be level to measure rocker from center point. The main thing is that the straight edge be tangent to the midpoint. I can measure rocker fairly accurately with a blank standing in the corner as long as I can reach the ends.
I completely agree with Lee that a straight edge can only be tangental to the midpoint at one spot. Sometimes it takes a little rocking back and forth and eyeballing but it is the best method I've found to measure rocker and I thank Lee for arguing with me long enough to convice my sorry ass.
Keep in mind I'm one of the dinosaurs that still hand shapes - start to finish, sometimes from rectangular blocks of foam. My old method of balancing the board on a straight surface and measuring from that surface up to the bottom worked OK for me but thanks to Lee, I've since joined the human race and measure with a straight edge tangent to midpoint. Balancing on a straight surface was prone to error due to things like the weight of a fin box tilting the board. I can even remember setting a finbox and weights to the tail at times to approximate tilt while measuring a blank... LOL.
Rocker is an important component of board design so some means of standardization only makes sense. The question presented on the tail rocker in the diagram might be presented as "Exhibit A."
Now if I could just keep my rockers from tweaking while the resin cures during glassing....
I fine that the rocker measurements in CAD are far more accurate than any other method.You look at the entire curve and not just tips. As far as a standardization? It doesn't matter if you don't talk to anyone. (LOL)
The “green machine” is finally done. Thanks to all for the advice and the suggestions.
Special thanks to Nick Palandrani (source surfboard) for doing the actual shaping and for putting up with all my crazy ideas on the design. Special thanks to Vince Broglio for the glass job and the resin tint as well as the fin recommendations.
Now all I have to do is wait for the swell to come up
