Piecing together balsa to make a stringer

I’m looking for a little help from the wood working gurus out there to help me with my next project. I’ve just acquired 3 pieces of balsa wood measuring 4" x 4" x 4’ for an upcoming 10’8" longboard. I really love the look of the Dewey Weber “Legend” with the 2" balsa stringer, and want that look on my upcoming board. Strength is not a huge issue as I glass my boards extremely heavy, probably 6 x 6 x 6 top and 6 x 6 bottom. Id love to here some suggestions on how to cut and assemble these 4 x 4’s to give me the ability to get a board 3" thick with 3" of nose rocker and 4" to 4.25" of tail rocker. I have a 10’ 8" walker blank with 4 " of nose rocker and 3" of tail rocker to work with.

also…I’m considering swirling the bottom and routering in a 2" x 2" strip on the top to get “the look” of a soild balsa stringer. Any ideas or suggestions would be greatly appreciated.

Thanks in advanced…

Bob

you basically have two options. You can just to a butt joint, angling the joint slightly to accommodate the rocker of the board. Option two would be to do a splice on the joints. This is what I would probably do. A splice is accomplished by cutting the planks at a pretty extreme angle and then gluing up that angle. The disadvantage to this method is that it causes waste and effectively shortens the length of the planks. The advantages are huge in terms of strength, especially with respect to something that will flex like a surfboard or a airplane wing. I learned this technique from my grandfather. He used it to fix old airplane wings in the war.

Maybe if you have a full shop you could bandsaw the pieces you have into some thinner stringer sized sheets. From there you could splice them together. Just a thought. I would make the splice so that it goes the thick way of your stringer. To explain that better if you were viewing the rocker of the surfboard the splice would go diagonally through the stringer. Hope that helps some. Good luck…

considering you have plenty of think time

and away work time …

to vondtruct thid stringer from thinner stock would make sense.

1 st rocker template aquisition

select 10’ rocker of dreamy scale

splice joint (shall we say scarf)is prefered

make 3or four of em to lam together perhaps using contrasting wood between

at three lams you would rip the 4’pieces into1’’ strips

set up your scarfs to match these lengths (each scarf 6’’ run?)

or less to give you more oversize

off seting scarfs is also prefered so make it three and nine

and stagger the joints so flex load isnt in the same place

contrasting lams will best be continious pieces of wood

consolidating strength engineering.

that said maybe I can go back to sleep.

…ambrose…

Yep, scarf joint is the way to go from what I know. Never tried it before though, so if anyone has any pics on how to go about doing a scarf joint on 3mm thick wood that would be nice. Also just found this link.

http://findarticles.com/p/articles/mi_qa3819/is_200112/ai_n9012173

Hope that helps.

http://www.oneoceankayaks.com/stitchglue/plyshophtm/scarfjig2.htm

Lots of info on joining thin panels of wood and the different joints you can use and their characteristics. You can make a jig for a circular saw, router, planer, whatever. The circular saw jig is quick and works well if you have a nice solid baseplate on your saw.

JSS

Thanks!

Raska23, Ambrose, Deanbo, Maxmercy…

Thanks for the helpful information!!! Looks like I can slightly angle the scarf joint upwards towards the tail to accommodate the tail rocker. Im a kindergartner in the wood working world…Thanks for the help. Alot on good sites to research this and get prepared before I tackle this project. Im on it.

oh yes,

ZAP A GAP CA

THE GREEN ONE

balsa guys love it and the glue joints are thin and are easily tooled

and it goes off quickly

great for the aadd…

…aaaammmmbbrose…

If you are after a 2" stringer, what I would do is rip your 4"x4" into 4"x2" and then rip again so you have 6 - 4"x1".

sketch you full scale aproximate rocker onto a piece of paper and then arrange you balsa to ensure that your balsa covers your rocker outline.

you can either cut the ends square (slight angle to make matching the rocker easier) or diaginol as suggested already.

glue up a 1"x4" stick so your rocker fits with in it.

Now do it again with the second 1"x4" so that the points of the second stick are offset from the first.

then glue the sticks together and now you have a strong 2"x4" stringer that will easily accomidate your rocker curve

4est,

Thanks for the tip 4est. I’ve got to start putting together a scarf jig when i get home so i can get a good start on this project. I need to source some type on 1/8" stringer material with a dark grain to butt on each side of the balsa stringer to give it some contrast and tie it all together. If I can find something easily, I may put one down the center as well to increase the eye candy… Any suggestions for a dark grained wood?

Bob

Quote:

Any suggestions for a dark grained wood?

Bob

Go redwood, kind of traditional that way and fairly easy on the tools.

I’d second the redwood.

call around to some “hard wood” providers

I was able to get some nice dry redwood; I think it was 1/8"x4"x8’, though I am not really sure.

I ripped it down to 1/4"x1/8" as I am using it as false stringer on a balsa compsand.

it would make for a great looking t-band redwood/balsa stringer.

post back with some picks when you get the stringer built up

4est, surfthis,

On the east coast its seems that redwood is a tough cookie to aquire. Called alot of suppliers today on the east coast who dont carry it. It looks like im going to have to do the cedar thing instead. My next trip home im hopeful to get the process started with the limited amount of tools I have. I will post some pics if all goes well.

Ambrose,

Ill throw down the zap a gap …colored green

Im sure I can do this without cutting my fingers off or gettin my fingers glued together…

T-band balsa stringer…no color…crisp white foam…blood red fin…best board ever…im feelin it.

Thanks again,

Bob

“Feed a man fish, and you’ve fed him for a day…Teach a man to fish, and you feed him for a lifetime…”

feed a fish a man

then where you gonna

get another man

stupid enough

to swim in a hungry fish tank

after some guy got eaten?

…ambrose…

glue the t-band pieces together

when you install the stringer

in the blank…