Here is one for the no wind days.
I'm putting this to the sea-breeze whiteboard looking for inspiration on my next step.
I'm trying to make a single tip board that will have a nice flex Patton, folds up to fit in a bag and has no glass in it.
I have tried to achieve this by laying the planks of the board port to stb not tip to tale and running 5 x1.6 mm SS cables tip to tail and tightening with m8 bolts.
The problem I'm having is I am not getting the tension and stiffness I need in the board. My next step is to up the size of the SS cable to 4.5 mm.
All ideas welcome.
Select to expand quote
All ideas welcome.
Congratulations, you just invented the first foldable skate ramp.
Call it Ramp-in-a-Bag.
Select to expand quotewaveslave said..
All ideas welcome.
Congratulations, you just invented the first foldable skate ramp.
Call it Ramp-in-a-Bag.
it has a name i like it. thank you waveslave
Hmm - looks awefully interesting - but can you share your design ideas ?? ie diagrams etc? As said above it just looks like a skate park to me :-)
Maybe even basic dimensions - width/ length/ rocker / volume / reason???
you probably know what a stressor is/does ive only seen the ones for slabs obviously.
but is there a miniature version? still imagine breaking one is going to cut ya arm off as opposed to chop you in half as the story goes.
what a weird idea...no glass... bends once to become a board goes rigid then when done goes back to being limp and flat....then you put it in a bag...made of wood....
care to tell us why you need to put a surfboard in a bag? is it for travel? because believe it or not there are alternatives... i get feeling you just had a couple lengths of pine laying around and decided to **** around but was there a drawing involved at some point?
Select to expand quoteUnhook3d said..
Why?
hydrofoil board that fits in your carry on when you fly
The timber is paulownia the w8 of all the materials comes to 5.1 kg.
I have not desided on final dimensions yet about 1.6m long and 510mm wide
the rocker is set by the shape of the edges of the unshaped blocks and the tension on the center wire.
Select to expand quoteKozzie said..
you probably know what a stressor is/does ive only seen the ones for slabs obviously.
but is there a miniature version? still imagine breaking one is going to cut ya arm off as opposed to chop you in half as the story goes.
what a weird idea...no glass... bends once to become a board goes rigid then when done goes back to being limp and flat....then you put it in a bag...made of wood....
care to tell us why you need to put a surfboard in a bag? is it for travel? because believe it or not there are alternatives... i get feeling you just had a couple lengths of pine laying around and decided to **** around but was there a drawing involved at some point?
yes the prospect of one of the cables letting go and taking my arm off is one i have thought about.
I am thinking the mark 2 will replace the cables with a carbon fiber strap.
no plans were involved just rum and an artistic eye
paulownia is not a particularly GOOD timber. they just use it in bed slats and kiteboards because its FARMED so theres no killing orangutans for it.
there is an ENOURMOUS wooden surfboard community out there that have done everything thinkable i would suggest having a good look at them.
honestly id just do a split board that is glassed...not glassing it is probably the only strange thing theres plenty of solid and hollow wooden boards i prefer hollowed and glassed. you can get pre cut kits or the cnc machine for just a flat 2d top is only $1000 and can make all the ribs useing that.
i think at the end of the day theres going to be far better transport options. but i can see where your going with the foil packed up and the board packed up all in a little bag, and i dont like split boards because the performance and durability decrease but theres no real negative to a splitboard foilboard cause your only useing it for the waterstart really arent you.... actually.....if you just put the foil on a bloody esky lid it would work just as well....
someone chuck a foil on an esky lid for me please!
Could maybe use tongue and groove joins instead of flat to flat (butt), might take some of the flex out.
Or get gnarly and use a staggered cut, tetris style. Reduce flex but lose strength as well
Reckon next on the cards will be an inflatable decked foil board.
Sawn off iSUP?
Select to expand quotetechtonic said..
Could maybe use tongue and groove joins instead of flat to flat (butt), might take some of the flex out.
Or get gnarly and use a staggered cut, tetris style. Reduce flex but lose strength as well
Reckon next on the cards will be an inflatable decked foil board.
Sawn off iSUP?
fish bone pattern with the timber so the grain takes some of the flex out ??
I get what your trying to accomplish. 1.6 MM cables = 1/16th Dia as a fraction which from what i can work out means you will need about 55 Lbs of tension per square inch. per cable and will give about 2 inches of deflection calculated.
2.5 MM cables = 3/32 Dia as a fraction with 66 Lbs of tension per square inch per cable and will give about 1.0 inch of deflection calculated.
both will change with temperature tho so the tension will fluctuate between say a 20 deg day and a 30 deg day? so the flex will not be consistent. 
and without a cable tenslometer i dunno how you will check the tensions when you assemble the board? unless you do it by feel and flex i guess?
post more pics tho pls
Rather then cable, how bout you do some precision nose to tail drilling, and insert carbon rods? once removed the board can be folded.
Select to expand quoteReevesy said...
Rather then cable, how bout you do some precision nose to tail drilling, and insert carbon rods? once removed the board can be folded.
Like skyshark rods? That could work.... but I also believe a simple split deck is enough to bring the size down to the same size as the foil shaft anyways so that will be the bags size.
Select to expand quoteReevesy said...
Rather then cable, how bout you do some precision nose to tail drilling, and insert carbon rods? once removed the board can be folded.
Here are some more pics of a wake sc8 I made a long time ago witch is the idea behind running the grain heal to toe not tip to tail see vary rough sketch.
I like the idea of carbon rods but it creates 3 challenges.
1 Attaching the ends of he rods and tightening them.
2 The rods would be as long as the board so they would need to be split in 3 and joined to fit in the bag.
3 how far will they flex bend before shattering (I like the idea of a carbon rod shattering a lot more then a ss cable cutting your arm off)
Select to expand quoteraggy said..
I get what your trying to accomplish. 1.6 MM cables = 1/16th Dia as a fraction which from what i can work out means you will need about 55 Lbs of tension per square inch. per cable and will give about 2 inches of deflection calculated.
2.5 MM cables = 3/32 Dia as a fraction with 66 Lbs of tension per square inch per cable and will give about 1.0 inch of deflection calculated.
both will change with temperature tho so the tension will fluctuate between say a 20 deg day and a 30 deg day? so the flex will not be consistent.
and without a cable tenslometer i dunno how you will check the tensions when you assemble the board? unless you do it by feel and flex i guess?
post more pics tho pls
thanks for the calculations
Also you would need to take into account wet and dry temp- flex
my thoughts on getting the correct tension on the cables was a tension wrench a long socket and a tightening order a lot like a head on a car motor
and feel a lot like pinging your kite to see if you have the right psi.
