After being infected by the speed bug at the speed event at Sandy Point I have decided I may as well try and get a board more suitable for speed sailing. Instead of going the normal route (like normal people) and buying something already up to the task, I have decided to experiment a bit and see what I can modify, to do something similar.
I have bought a damaged 2005 JP RWW 76L board and have already added a powerbox to it and added twin footstrap inserts to the back. The next thing is to add some inserts at the front footstrap positions so that they are much closer to the rail.
So, I guess at this point I am asking 'what is special about the shape of a speed board'? Does a wave board have too much rocker to be useful as a speed board? If I modify the rocker and the vee, what should I aim for? It seems that when up to speed, the board only really sits on the section from the front straps back, so does the rest of the board matter?
...Yes, I know I should have used a tuttle box, but I already have some good powerbox fins... the next version can get the tuttle box.
Well I've just added 8mm on to the tail of an old 84 litre Jp wave board, reducing its tail rocker from 10mm to 2mm. Doesn't seem to go any faster, but it gybes beautifully, still feels like a waveboard, not that I'm all that qualified to judge waveboards. So I'd be interested to know how a slalom fin and outboard straps have affected yours? I'm starting to think that the subtleties of board shapes are not that important.
The tail rocker is an area I have been wondering about. It should be easy to fill, but what differences do you think it will make?
Well I'm not the expert, I have mucked about with the tail rocker on only 3 boards. I was just aiming to make the wave board more suitable to me as a high wind board. The tail rocker on a wave board makes them pretty twitchy and non-directional in chop - just what you want if you're a wavesailor but I'm not used to it. I was trying to make the bottom shape more like that on my Naish Supacross from which I've been temporarily parted.
The Naish is still better, I've put it down to the strap locations and a nice slalom fin that's balanced to the width of the board.
I think being comfortable in the footstraps is the most important thing about a board.
And we've both spoken to the worlds fastest 60 yo who tells us that at speed on flat water there's hardly any of the board in the water so "What's it 'kn matter?"
Doesn't Tony Wynhoven mainly use wave boards at Sandy Point and regularly posts 40+ knot speeds? It could be Craig Spotiswood....not sure which of them
Anyway, they prove obviously that a lot of the speed comes down to ability and quite possibly the rig and fin as opposed to mainly being the board. A speed board may be more controllable due to its tail shape.
Just my 2 cents worth of thoughts on the matter ![]()
Within reason, the fin is far more important than your board. It's Craig that uses the wave board, but when he goes faster than 40knots on it it's because he's using a 23cm KA speed fin (Tuttle) and because HE IS DA MAN
Hey Formula, I'm on a similar project at the moment modifying an old bic adagio slalom board. The main problem with the old board being too long and the distance from tail to mast track too far, as was normal back then. So I've chopped both ends, reboxed with powerbox (yep too many pB fins to go over to tuttle). May need to put some new front strap inserts in as the stance is now a little narrow but that can wait. I'm just guessing on the rockerline but I've ended up with flat for the last 40cm, then another flat of about 80cm (original rocker line). Here's a couple of pics.
I've also raised the nose rocker a little and softener up the forward rails that use to catch in the chop. Also need a respray as the psycho graphics that were cool when I was 20 something are just too much now![]()
surely by lopping off a sizable section of the tail as you have done will have major ramifications to the dynamics of the board in its setup. Your mast track now will be a long way back and I am only hypothesizing here, but I would have thought the balance points will be screwed significantly. A mate and I back in the 80's made our own slalom boards and whilst I moved on and bought a new style board he thought he would be able to drop a new mast track into his behind the other one and It would work fine. It didn't. The board was designed (copied from a Tom Luedecki design) to work with the track just where it was. As I presume from lots of R & D by BIC yours would too.
Are you planning on moving the track a bit further forward from where it has now ended up?
I would have thought if you were going to modify an existing shape board then you could really only reshape (that is not shorten) the tail and lob off a nose section as this is not as important as the tail.
Happy to be proven wrong though ![]()
Hi Rex,
THere's a good chance the board won't do anything special as I'm not a fast sailor anyway, so its just a hobby sort of thing using an otherwise worthless board.
My thoughts on the balance of the board was mainly to bring the board more inline with modern board design. Most boards seem to have their mast tracks centred around 130cm from the tail, the old adagio was by memory about 155cm so instead of moving the track aft I've shortened the tail. Most boards nowdays are between 235 -245 long, so I've chopped the front as well to get a 235cm board. These measurements are fairly common to see on modern slalom boards of 57cm width so I'm hoping it will work out.
But I'm not gonna lose any sleep if it sails like a dog.
Mr Love, Yep a "Sexy Love Muscle 62".
Sailpilot, Great that you are giving it a go, for old board retro recommend you add deep cut outs.
Here is my Speed Board Retro Fit.
Started life 15 years ago as an old 9'2" Course Slalom board.
Board was originally built "light & stiff" overloaded with carbon, 10mm foam core carbon stringer on the bottom forward of the fin box, carbon uni under the foam
core with Full Carbon wrap.
To Retro:
1st/ The Deck, Rails, fin box, mast track was removed.
2nd/ Rails & Deck reshaped, wooden deck vacumed on.
3rd/ Cuts out added to improve board trim from the old rocker shape.
Result:> 4" thick, 47cm wide, 240cm long, 30cm wide tail. Top Speed so far 43 knots
(25 knots of wind).
Conclusion: Time wise its easier to build from scratch, only reason I retro this
build was the carbon content.
Next Board starts from the Computer & then Precision Milled.
Okay, it is good to see I am not the only one playing around modifying boards...
I give up icesurf, what is the box section cut out ion front of the mast track on your board for? Is it a convenient place for your lunch
or a gps?
Nice one Icesurf, those are pretty serious cutouts. I had some smaller ones in mind but will think abit more on that yet.
Mr Love, you seem to have a nice shape to the 'muscle' what density foam are you using and whats the plan for your layup? Any estimate on final weight?
Peter Ross at OES is building the Board. It is full Carbon/EPS/Corecell. He is getting Carbon from the States especially but could not tell you the exact layup.
I told him I was happy with anything under 5 Kilos.
Seeya Martin
Icesurf -
Pretty serious 3 axis machine you are building there! ARe you going to do boards or going by the beefiness of the rig something heavier? must of cost a bit for those lead screws and linear rails. Im jealous!![]()