Curious to how others shape thier concave in with their rocker. I read a recent thread where **EverySurfer **said ‘‘I shape in the stringer rocker first, then I lower the rails to final
contour. Way more accurate than shaping a flat bottom, then adding
concave’’. Which is what I do, shape a flat bottom then add concave. I plan out two rockers, one before the concave and one after, basically middle rocker and rail rocker. For example if I wanted a finished rocker of 4’’ in the nose and 2 in the tail with an 1/8’’ deep concave at midpoint, I would first shape my rocker at 4 1/8 and 2 1/8 knowing the concave would lower it. I then I would cut my desired concave in right down the middle with my planer and then shape it to the rails. Since I typically measure my rocker every 6’’ to 12’’ there is some math required which has me thinking this is not the best way. Though I feel by shaping a flat bottom first, I can keep both sides exactly the same. How do you eat your reeses?
why is my location in japanese does anyone else see that
Hi Dtb,
Me again. Yes I see your location in japaneese too.
The standard way of shaping the bottom is to add the concave last, but when you call out rocker numbers, they are done along the stringer. So the conventional way, you cant really measure what you are doing, because you don’t have a baseline. You can sort of “fake it” and “just follow the blank” but you aren’t really measuring. I always use a rocker template to get the first curve right.
The stringer first method gives a hard curve that everything else is based from. And it saves the shaper from the “oops, I wanted 2 1/2” thick, but 2 1/4" is close enough".
It does change the planer technique. The nose on the raw foam and the tail on the previous pass goes different. You don’t point your planer’s nose toward the stringer, but instead the nose of the planer is pointed outward toward the rail. Starting from the center, adn working outward to the rail.
Your first stringer pass takes a little more care as to not cant the tool, and have one side deeper than the other. It takles a steady hand, and keeping your eye behind the planer.
Thanks for your explanation, i’m considering trying your way cause my way seems to be too much math. I have to first determine my finished rocker every 6’‘, then determine what the bottom contour will be at that 6’’ mark, and then I have to do the math to figure my pre-contour bottom. Since I’ve been doing this for a couple years, I made a exel spreadsheat, where I type in the finished rocker and it calculates the pre-contour rocker.
Easier way.
Go to home depot, get a 100 foot tape measure. Google using a tape measure as a compass. Draw a 40’ to 50’ radius arc onto a piece of plywood. That is your tail rocker from midpoint back. 50’ radius is more for a fish, or gun. 40’ radius is for a standard
thruster. Less than 40’, and you will start loosing drive off your
turns, but turn easier.
Draw another arc at 20’ to 30’ radius. That is your center to chest area rocker.
Draw a 6’ to 10’ arc. That is your nose to entry rocker.
Take your three templates and blend them so the curve has no bumps. Trace onto a final rocker stick.
Enjoy
Plow the stringer w/ the planer inline tappering depth in lightly from nose … dropping in the deepest cut where the deepest concave is desired and tappering out zero depth toward tail.
(If you’re not adept at single tappered depth cuts the then do multiples e.g. 1/16 w/ 20"run, then equi-center overpass 1/16 w/ 32", then 1/16 w/ 48", also tail to nose passes typically yield less rocker curve especially if your back hand heavy. Finally, If you need outline offset reference lines and depth tranition marks apply and follow them.)
Next pass step up and out toward the rail outline making arced pass, typically a little further tailward than the primary stringer pass,
Next pass repeat stepup and approximate rail curvature on final pass length is + or - the 2nd pass’ lenght depending on the overrall bottom design.
If you’re doing a double concave inside an over all single then blend out your steps and add a primary plow centered deepest at max concave location 1st and repeat steppin up an out to rail as well as in toward the stringer.
As always pay attention to the blade attack angle and the cut width that results.
I eyeball my rocker.
Everysurfer,So thats how you make your rocker templates, thats a good idea. I have made large circles with stringline before, so I know exactly what your saying.I have quite a few rocker templates that I took off of boards I liked over the years and I break them up in three sections (nose,middle,tail) so i can blend and adjust to bigger or smaller boards. And what peterg explained is pretty much how i cut in my concave. I make a single cut down the middle starting my planer closed at the nose, wide open at the sweet spot, back to almost closed out tail, then I blend that in.
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dtb, I make and sell rocker-bars that make rocker templates a breeze. Search under “tools for sale” on this site. Barry
I hope this link works. http://www.swaylocks.com/surfshop/Detailed/8387.html
Yea cleanlines if it looks good it probably works good, but I’m a numbers guy. I see everything in numbers, which can be overkill. I need to stop relying all on numbers and trust my eye too. Maybe the next board I shape i willn’t draw up, just wing it and shape it by eye. That kind of sounds like fun, Im going to do that.
“I eyeball my rocker.”
What I don’t “eyeball” I “feel”.
Cleanlines,
Not an argument, just a question. How do you eyeball a curve? Graduations of 1/16" per foot is too small for me to see. I have to measure.
Hey dtb if you haven’t already checked it out it would be worth going through the 'FAQ, Beginners Area, Read First Sticky Thread at the top of the general forum. Of particular interest is anything that Bill Barnfield has written.
This one is a sways epic http://www2.swaylocks.com/node/1018545
Using an electric planer and techniques: http://www2.swaylocks.com/node/1021525: This thread had a video with Bill and others giving critique on shaping involved in the video.
Hey Mark, I’m a kook so keen on hearing Cleanline’s answer too but I think it’s fair that if you have the right deck rocker for your design and you aim to hit the thickness measurements along your blank, your going to come very close to your desired buttom curve. I’ve found that turning one side light off does wonders for seeing bumps down the stringer. There’s no point in hitting incremental measurements at 6’’ appart if there’s a flat spot inbetween.
But each to their own and thats the fun thing about it is that everyone works out their own style.
Happy shaping.
I shape what I want. All of my boards are one of a kind and I am not trying to duplicate anything. I may measure the rocker at the tip of the nose and tail but thats it. I just try to make things flow. You have to trust your eye in order to become a good hand shaper. Not saying this is for everybody but you asked and I answered.
I gotta tell you a story.
back in the 70’s I was production shaping and we had a surf team. I shaped one of our best riders a board and he came in and proceeded to start measuring the rocker using my long straightedge and a tape. He loudly pronounced the rocker all wrong with “to much in the tail” etc etc. I told him to go try it out. He tried it out and came back and told me it sucked and he wanted another board. I said no problem come back in a week.
This board was clear with red and yellow resin pins. It was a sanded finish. I sanded the pinlines off and shot three more pins in red white and blue. I also put a pin around the finbox.It looked like a different board.
A week later the "pro’ came and picked the (same) board up. He checked the rocker and eyeballed the board and gave me a big thumbs up. He said it was the best board he had ever ridden.
A lot of it is all in your head. Which may be empty.
Thats a funny story, hey cleanlines do you remember selling a skil 100 on ebay a year or so back, if your the right guy we talked on the phone and you mentioned doing the glassing on the master shaper/glasser series. I asked you about skil planer technique and you told me to look up terry martin, definetly good advise. Anyway if your not that guy, my bad.
Cleanlines, I know this has nothing to do with rocker but, I love that story. I have a sander friend who told me that a very well known shaper (lets call him Waaanadu) brought back a board saying it was too heavy. (it was under 5lbs) He told the shaper, “wait here I’ll sand it some more” . He took the board, went outside, smoked a cigarette, came back inside, then handed the board back to him. The shaper said, (much better). You’re right. Sometimes it is all in your head. Especially when your head is that big! HAHA! If you can’t laugh at yourself, let me do it for you!
Barry
Yea I did the Master Glasser video. It is still being sold by Damascus productions. U can get it at Foameze and in Australia somewhere. That video of Terry Martin shaping is a good one. The Master Shaper vids by Jim Phillips are like encyclopedias. I also mess around withSkil planers and have bought and sold a few on Ebay.