I have ended up with a stringerless eps blank and I am at a cross roads. The board I am planning on making is to be 5’8, 20’’ wide and 2.5 deep so not too long and relatively fat. After searching up different stringer alternatives I’m wondering if it would make more sense to try and put a stringer into the blank than to try and deal with using carbon, or attempting a parabolic type stringer.
I have done quite a few repairs and am comfortable playing with standard glass although this will be the first attempt at making a board.
To get a stringer put in, I would need to drive an hour and wait a couple of days.
Would it be much more complicated to use a carbon stringer or a parabolic stringer? Am I better to get a stringer put in? I can’t see too many youtube videos on people hand shaping stringerless boards which is slightly off putting.
I put stringers in EPS blanks all the time. It’s not difficult. However, these are straight stringers not parabolic. As far as doing a stringerless, it’s not that difficult. I mark the center line (chalkline) then drill 1/8" (3mm) holes in the blank every foot or so about 1" deep to keep the center marked on the bottom. The biggest difficulty you’ll encounter is the additional flex you get when shaping. You’ll need to pay closer attention to keeping your blank supported. Good luck.
You didn’t mention what density the foam is. That will affect the stiffness, which will affect how much it flexes while shaping & glassing. Hopefully this is obvious, but it will also have a bearing on the glass schedule you choose.
Having said that, it’s not hard. You can also look at it as a cheap and easy way to see what it’s like to shape a board. You’re not married to it. I’ve never seen a commandment that says every shaped blank must be glassed and completed. If you get it shaped and aren’t crazy about the final product, you can just chalk it up to being a good learning experience and decide what to do from there.
You could also do a glue line stringer, just to gain a little stiffness and have a reference for shaping.
You can make it discrete or make it a bold color.
I had an EPS SUP blank that I glued in the wood stringer upside down. I ended up cutting it out and just using a foaming PU glue line.
I used a hot wire with two straight guide boards to split and re-split that blank.
I don’t seem to do well with long blades on saber saws.
Always check/set the rocker before glassing.
I wouldn’t be too worried about the stringer. I’d be worried about how the hell I’m going to shape my very first Blank and not have it turn out wonky. Of course Asymetricals are pretty popular these days so I suppose you can tell the bros that you intentionally shaped one side 8" of the center and the other 12" off center. As mentioned above; a glue line is still “Stringerless” . If the Blank is “Slab Cut” EPS it can be easily split and stringered. Even a hand saw and a few bicycle tube strips in a pinch. Lowel
use a pencil and a ruler to find the center.
Stonebummer has a massive archive of stringerless boards that he refuses to share. Post up those photos Stone Man.
Just draw a centerline. It’s not too bendy, as long as you support it right, aka don’t have the shaping stand supporting the very tip and tail. I’ve done 6 boards and I’m working on #7. I don’t think they’re that difficult relative to stringered blanks. If anything, you don’t have to worry about having a high stringer, which messes with glassing and sanding.
Make a good template. If your template sucks then it’ll be hard to get anything right. That thread about the masonite templates is a good read. Draw the center line, line up your template with that and you’ll be good to go.
All of the advice regarding the centerline is worth accepting. However you do it - stringer, glueline, pencil or whatever, it will help you a great deal to have that reference. It is worth some extra effort to get it straight. Many boards have been mis-shaped due to wonky stringers from the blank factory. Bill Thrailkill and Jim Phillips have mentioned that it is sometimes necessary to snap a chalkline for reference when a stringer is not straight.
I must be clueless. So how the hell do you maintain a pencil or chalk line reference point thru the shaping process? The only method I have ever seen that would work is the nail hole method down the center at desired thickness. Matt Kinoshita knows what I am referring to.
I put a couple of pencil holes along the CL by twisting my pencil along the line. I sometimes have to mark it a few times during the shaping process. On the bottom, I lay a line of 1/4 inch tape down one side of the CL and use that to mark fin locations. Sounds like a pain but so is shaving a stringer. Under 6-0 and about 2.75 inches thick, I don’t use stringers. I do the rail channel corrugation thing, and lately using the carbon fusion tape from GraphiteMaster. And we don’t have waves of consequence over here.
Keeping a clear centerline can be a bit of a pain, but it’s not that bad.
On the bottom, you mainly need it for templating/cutting the planshape and at the end for setting fins. You don’t need it for shaping rocker, and with EPS most people handle thicknessing and foiling in the deck.
Deckside, it’s not really necessary to have a centerline.
It sounded to me like the OP is a first time shaper who scored a free blank to play with, so I was trying to save him the drama of splitting a blank and gluing in a stringer. Trying to keep it simple.
Personally, I like the idea of a glue line and plan to do that with the foam I still have before I hotwire another blank.
1st board?
Is the blank a rectangular slab of EPS with rocker, flat without rocker, or a pressure molded blank that looks like a fat surfboard?
What tools will you be using, a planer, surform, sanding blocks?
I’ve shaped stringerless EPS with just a surform and sanding blocks made from 2x4 and sanding belts. I even did a couple using a large box instead of a stand.
Softer EPS tends to be somewhat floppy, so you need to have decent lighting to make sure you stay on track.
Once you have the blank bottom the way you want, get the top close to the thickness you want. Use a long straight stick to make sure your rocker is where it should be.
You can make a full template then you don’t have to be worried about the center line. Just keep the template straight based on your rocker.
George Greenough showed Tom Curren how to make a full template with a large piece of paper folded in half. For one offs I do the same. You can stand on it a get a good feel for what it will look like under your feet. It keeps both sides symmetrical too. Once the outline is cut and you have your thickness profile set, draw lot of lines along the rail, the deck and the bottom. I make a line at 1/2" on the bottom and on the rail along the bottom. Then I’ll do a line at 1" and 2" along the rail. I’ll do lines along the top at 1" intervals up to 4". These are my guides for the rail bands and they also show me the thickness profile. If you keep it a little thicker than you want it to end up, you’ll have enough to cut to the lines and they’ll go away as you shape.
I do a lot of stringerless boards. For strength, I make sure the rails have a lot of glass. Do double layer wraps that go at least an inch around. You can shape a slight beveled edge (like the Stewart hydrohull) on the bottom side to make up for the extra thickness of the glass.
I have EPS boards with lots of glass that are still reasonably light. Very light compared to my Poly boards, but those don’t have extra light foam.
Here’s a picture of the box I used to shape my first board or 2. I had to do it on my knees too.
Good luck.
Sorry McDing if I was unclear. When I do a board I follow a step-by-step process. Assuming I have a good template pattern to work from, I would just use the pencil line (stringerless/no glue-line blank) as a reference in transferring the outline. Once it’s laid out on the blank I don’t use the template pattern any more on that shape… it gets cut, squared off, and all the rest without the template pattern. I try to true the outline cut right to the line, square it off, and not get too carried away scrubbing the rail edges. Ideally, the rail tuck and rail crown meet at the apex and require just a touch of the screen to finish it off.
