increase tail rocker to help prevent pearling in bigger waves?

heard this recently. can't remember where. what do you guys and girls think?

i think the logic was that a flatter tail rocker doesn't fit the curve as well and forces the nose down.

seems to make sense. you can keep mild entry rocker for paddling and increase the tail rocker for those steep drops.

I agree with you Chrisp, the tail rocker will help to fit the wave better for cleaner drops. Of course, it’s a balance between early entry vs. smoother drops. I’ll opt for the latter. 

Its Bob McTavishs theory behind his G2 gun design. He explains it on Youtube somewhere. Sounds good, lower the entry rocker for an early takeoff also. The only worry is that you won’t be back far enough on the board to raise the nose. I guess it will work for some and not for others.

Hey Chris.  My 6-0 five fin seems to red line at about 1-2 foot overhead.  At that size I start blowing drops. I thought it was a size issue (of course I never consider it a skill issue haha), but the board has less than 2" of tail rocker (1-5/8"?).  It’s obviously very fast on flat waves.  I’m thinking the theory you mention is a good one.  It’s always a compromise.  How much tail rocker do I want to add- to help with drops and to loosen the board off the top vs. how much speed am I willing to lose?  decisions decisions…

Hi Chris,

I played around with this concept, and what I came to was something different.  Tail rocker determines how far the board projects on a turn.  Less tail rocker, and your bottom turn is going to drive you down the line.  More tail rocker will give you a tighter radius turn, but with less speed.

If you are blowing late drops, add more vee at the fins, and go narrower in the fin area.  Less surface area will sink more.

Lastly give a little more meat in the back third of the board…  That is to put your natural paddeling position back a touch.  When you paddle forward on the board, you jump up forward on the board, and all your weight sends the nose down the face.  If you can scoot back toward the tail a touch, and still paddle with the board level, you will jump to your feet a little further back.

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This is my steep wave board.  A little wider under my hips when paddeling, but around a 13 1/2" wide tail

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I was living on a sailboat in Hawaii in 1972 and remember meeting a girl's younger brother who was excited about his new 'reverse rockered' shortboard.  It was a single fin semi-gun with a flattened entry rocker and boosted tail rocker. 

I also remember some of the guys at Natural Progession playing with the concept around the same time in California.

For kicks, try shaping a scale model and experiment with pushing down on the tail... it really does cause the front to lift.  It also fits a steep face better.   There is a point of diminishing returns if carried to extremes.

 

 

 

I'm in the school of rockery boards with a straighter fins set up. A rockery board will fit in steep square waves a hell of a lot better than a flat hull or fish type set up.  Keep the board rockery so it fits in the wave better. Then set the fins with a tad bit less toe and cant.  So now the board turns more from the rocker line instead of the fin cluster back section.   What you end up with is a board with less drag in the ass from the fins, but able to fit in those places where a lot of boards have a hard time. The board will also have lots of drive.

were talkin about waves with a bit more consequence...right?  So your really not worried about generating speed? But you'r worried about managing speed.....or sheding speed.  The point of more rocker in the tail is the ability to stand on the tail and pull the nose out of the water on steep drops......But you better combine it with nose rocker.  If you don't you're going to have to take off on an angle so you don't stick the nose in the bottom of the wave..when it starts to suck out.

Also the rockery tail will allow you to stall and shed some speed when needed. 

So make it rockery, just don't set the fins up as usual with 1/4 toe and 8% cant.  do it more like 4% and 1/8 toe.  It will fly, and be extremely managable on the drops.

So what's all this talk about making an 8 ft board?  Don't you know that 8ft boards are too big to surf on?  Why in the world would you want such a big board?

 

how much nose rocker and tail rocker do you guys put on your gunish type of boards?

Just wondering because I am doing a 7'6" for myself next week. single fin wide point slightly forward, 2 3/4" thick 19" wide 12 3/4" Nose, 12 1/4 " tail. Vee throughout, but a little less under the front 1/2 of the board.

I was planning on 5" nose maybe 5 1/4" and 2 1/2" tail. I want it fast, but don't want my drops to be super sketchy due to lack of rocker. Is this enough rocker?

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I was planning on 5" nose maybe 5 1/4" and 2 1/2" tail..... Is this enough rocker?

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More than enough.

Thanks for the response.

If it is more than enough, how much less could I go with? I want to make this board as versitle as possible in big waves(ie. mushy and hollow,powerful and rolling, etc.). Probably going to surf it in head and a half to as big as I can paddle into on it.

 

My 6’-8" x 19 1/2" Channel Islands K-Step up has 5 1/2" nose and 2 1/2" tail.  Scale up accordingly.

US Blanks 7'8" EA just follow the blank rocker. Something like 6 and 2 5/8? Cut it to 7'6" and your like 5 1/2 and 2 5/8.  Maybe push the tail. I like more tail rocker. ....................................................................................................but then I hate seals and like beer?

I'm kinda going for a less "shortboardy" gun. Not retro, but inbetween. The foil is thicker up under the chest, and i'm gonna put a beak nose on it.

Most people say a good amount of tail rocker is good for making steep drops vs a low tail rocker for more drive and long arcs off the bottom turn.

On the other hand I am seriously confused by Dave Parmenter's description of a traditional big wave gun in his abstract "anatomy of a surfboard"  http://www.surfline.com/mag/features/anatomy/anatomy_textonly.html  see board 5. He states that while entry rocker is 8" the tail rocker on this board is 1.75" and describes how the other factors of this design go well with this relatively low tail rocker.

He also describes the reason behind this tail rocker and states that more current guns have 3 1/2"+ tail rockers but reminds us that curves create drag. We are talking about a 10' gun with 1.75" tail rocker.

This post is about a gun that is 2' shorter than this and I am not trying to hijack the post but since we are discussing gun tail rocker, I believe that some feedback from the gun experts in this forum can bring some light into the discussion of gun tail rocker. Thrailkill, please I know you have got a good answer.

Along with the tail rocker, I feel pretty strongly that the tail outline is of major concern on boards like this. I have a 7’6" Semi-gun shape from the 80’s that is my go to in anything over DOH, and / or steep & ledgy. I don’t realy remember the rocker (at least 2.5", fairly sharp, almost kicktail), but the thing that makes it work is the combo with the rounded pin tail shape (roughly 13.75" and fairly thin compared with most guns I’ve seen). During a really steep drop, I can get the board up on a rail so that the side fin (its a thruster) is engaged, and the nose (and it’s rocker) are working. So even though the “tip to tip” rocker might not fit the wave, the outline / rocker combo does.

That poor board has a serious right twist in it from the few select breaks it gets out in around here!

 

Geez. 8" of nose and less than 1 3/4" for the tail on a board that long? that doesn't seem right, is it a type-o?

Along the lines of tail rocker as compared to the outline, I was wondering what a 7'6" board with a tail as pulled in as the one I mentioned earlier ( 19" wide and 12 1/4" tail) could go with as far as rocker is concerned. It has a pretty pulled in pin, not really rounded pin. leans more towards gun rather than semi-gun. I mentioned earlier 5" nose and 2.5" tail rocker, and Mr. Thrailkill said it was more than enough. how much more could I lessen the rocker without going overboard. less than 5" nose and 2" tail? I'd rather have it too fast than too slow, but I don't want to have to stay at home when the waves get steep, hollow, and ledgy because my board can't handle those kinds of conditions.

Must have been a type-o in that article, maybe he meant 2.75". Go with Thrailkill’s advice, he is a very experienced gun shaper and big wave rider. As someone said somewhere: “designs have changed, physics have not”.

Must have been a type-o in that article, maybe he meant 2.75". Go with Thrailkill’s advice, he is a very experienced gun shaper and big wave rider. As someone said somewhere: “designs have changed, physics have not”.

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 I'd rather have it too fast than too slow......

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The marriage of 5 in nose, and 2 to 2.25 in tail rocker, to a 7' 10'' x 21'' sq tail gun, was my ''go to combo'' for more than a few ''magic '' boards for myself and others.   I could ride the same board in 3 foot beachies, as well as 15 foot at Sunset, and did so on many occasions.    Those boards were typically in the 12 to 14 pound weight range.   Send me money, and I'll make you one.   

Thanks for the help.

I'd love to get a board made by you, but I'm too addicted to building boards. I also don't have enough cash so building my own is the cheapest way to go.

Again, thanks you so much for your time and great advice here. I always appreciate insight from the pros.