I'm finding my 50cm board a bit too big much above 25kts, especially if it's choppy.
I had a go on the Thommen, and it's fine in the strong gusts but at about 50l horrible in the lulls!
I'm getting too old to wallow around up to my waist in water.
So I'm considering making a board with a stepped bottom, somewhere around 42/45 cm on the bottom and 50cm on top, the step about 20/25mm deep.
This will involve a bit more work than a conventional arrangement, so what happens if the board is fairly thick?
Say 130/150mm for 42/45 cm wide, does it make it unstable, increase wind resistance, or make it more likely to do that rail trip thing when the fin lets go?
Why is the Thommen and some other speed boards so thin?
Ian's asymmetric ideas have also got me thinking, but first I need to decide how to get a bit more volume.
Any ideas, thoughts, suggestions all welcome.
Hey Dan. If you read this. If you ever want to sell that 'step board' I would like first dibs. 
Oh, you haven't seen it? It has a 'step' under the mast base and rides on that point and a short area at the back as well. Very stable longitudinally. Great concept for a tandem I recon 
Put an image for you to see.
Rear half is dead straight. Same width and thickness at mid section as at tail. It trucks back upwind with even the smallest fin.
It rode too flat. He has since added another 2.5cm? to the bottom before the step. Of course bringing the step further back would have the same effect.
Dan not sure of fin posie. (Whether it is any better than normal.)
Mind you, I think Dan did close to 44s on all his boards.
Hi Decrep . I have just finished CAD designing a 43 cm speed board . It is similar in concept to Chris's Carbon Art boards , very parrallel , wide in the nose with a fairly flat rocker and quite a bit of V . It differs in that it is a little shorter, I have raised the rocker a bit in front of the mast and added parrallel concaves that run out at 600 OFO . I have also put sharp wingers in the tail rather than the pintail .
Like the Carbon Art I have quite volumous rails but I have heavily scooped the deck out . This aids in getting the volume up a bit yet keeps the center of effort down low . It has come out at 61.5 litres which is fairly high for a board as small as this and good for my 90 kilo's .
If you want a board that has reasonable volume perhaps you could make the rails quite "chunky" through the centre of the board but scoop out the deck alot .
I don't have any images of my board at home , they are on my work computer. I,ll stick them up next week and if you are interested I am happy to send you the file.
I am hoping to get somebody to build it for me later in the year . Any offers?????
Back when I worked at Bombora, we had a board maker by the name of Bruce McKee. He was a top bloke who was one of those guys that constantly questioned and looked at ways of improving anything he was involved in. He pioneered wakeboarding, he was one of the best free skiers around, he ended up desiging the Bombora Capricorn as well as making modifications to many of the existing models on sale at the time. He shaped Surf Skis for John Christenson (world champion) and later on moved to France to shape surf boards for names like Sonny Garcia and Occy. Anyway, while he was at Bombora was the era of Pascal Maka and Bruce caught the speed bug good and proper. Totally by chance I came across his personal website the other day and on it are some great pics of some of the speed board designs he shaped back then (late 80's) which are pretty much the forerunners of what I think Dan has made.
The link to his site is http://www.mckeesurf.com/brucemckee/windsurf.htm
This will take you straight to his Windsurf page and once there check out the stepped board collages he has put up. Some of the designs are amazing like the ones that look like Formula 1 boat hulls. They were a bugger to glass due to all the needle noses and curves etc. We had great fun trying them out in various locations but he was very protective of his designs so they never really got too much public exposure. A shame really because I think with some modifications there was some real potential. Hell I'd love to dig them out again now and see what they could do.
It's a cool site showing some of his hundreds of surfboard designs too as well as his 4 fin system he has recently teamed with FCS to produce.
Decrep I emailed him the other day and am sure you could do the same if you wanted to pick his brain on some ideas. I think considering his track record he knows what he's on about regards shapes.
Cheers
Did he design the Astro Toy?
That was my first short board and i totally loved it and still think to this day that the hull design was great
Was that the one with the clinker built hull? I had one. Great board. People were so impressed with them at the time that one or two carbon/glass fibre copies were built. But I suspect the polypropylene flex was essential to the magic.
Mr Love, yes I'm thinking of keeping the mast track as low as possible, may be scoop it out so that when the mast is at 90deg to the deck, it's just about touching it, but a closed well would probably fill up with water, making the board heavy, it'll need some opening at the back so it can drain.
Nebs & Bender were around this arvo and some ideas have emerged.
I think a step all round the board is going to be much too hard to construct, so now I'm thinking of just the last meter or so.
Think having the feet out a bit enables them to be higher without increasing the rolling moment on the board, just might need a slightly longer fin though.
Your board sounds good, but I can't offer to build it for you, we're going on a European trip later in the year.
Sick_em_rex,
I see what you mean, some interesting stuff there, but not really what I have in mind.
Still got the mag too 
Their problem was the inconsistency of the filling causing some pretty dramatic holes and delams occurring which resulted in a lot of returns.
Hi Decrep , I will stick some images up tommorrow for you to have a geek . I have also been thinking about an assymetrical "stepped" board for a while but as yet have done nothing. The one I have modelled is symetrical as has no cutouts or steps , just wingers like the Isonics.
Peter Nitschke is building me a Bump and Jump board at the moment that I designed but is off to Brasil next Saturday for 2 months . I was hoping to get it built for speed week but I guess it will have to wait unless anyone can suggest somebody else who could build it ?
Hi again Decrep ,here are some quick screen dumps of the board . The spooning out of the deck and the concaves aren't as severe as they look on the images , the concaves are only 1.5 mm deep at 1500 . I am going to widen the tail a touch in front of the wingers ,I think it tapers just a bit severly .
You are welcome to the file if you wish .
I have also stuck an image of the Bump and jump board in the gallery ,I designed it and Peter Nitschke should have finished this week .
I have an epoxy version of the Astro Toy hanging in my garage. Its quite heavy and doesnt seem to have any foam in the nose section but ist perfectly sailable.
Its from Bob Mctavish and is called Shock Treatment, no idea why. If anyone wants to check it out give me a call.
It looks like Chris' first CA 50 which had a nose like that before they decided to round them off completely.
Should be good. Whether the tail trimming offers any benefit only trial will tell. It is a better way than cutouts in my book but not sure if necessary on speed guns.
Hi Yoyo , yep ,obviously heavily influenced by Chris' brilliant Carbon Arts , but in reality it is quite different. The rocker is not quite as flat and I have the double parrallel concaves in the front running out to flat V. I thought the Isonic type wingers were a great way to narrow the tail down as well as get that really clean release of the rails. I do think I need to widen the board a touch just in front of the wingers though ,maybe only 2mm,s a side .There is no reason for the arrow like nose shape other than aesthetics , I thought it looks fast!!! The main thing was to have the wide nose to produce the lift to help unstick the board.
I would love to make it , but I don't have the time or skill .Hopefully when Pete Nitschke gets back from Brasil he can build it for me.
another way of lowering planing threshold of the narrow boards is to introduce a single entry concave (scoop).
Just couldn't resist today, there's a poor trapped speed board in that blank trying to get out, and it's calling to me for help.
Think I've found the bottom of it.
Outside rail is 50cm inside 45cm, will probably make it smaller, I just need to sail some high wind boards and see how they go.
Any comments on negative aspects of this idea, please don't hold back. (or positive ones too of course)
And obviously in case you were wondering, the rails and thickness aren't going to stay like that.
At the moment it's about 130 litres, I'm aiming for a bit over 70
Hey decrepit, not sure if you've built a stepped board or not before. The first time I did one and put it in the bag to suck the top on, the stepped section didnt have dcell on it and the foam compressed realy badly (that one ended up in the bin) I've done a couple since and put a layer of 4oz over the stepped section to give it some strength when it goes in the bag. Hope that makes sense.
Hi Decrepit , I could print sections ect for you but it looks like you are having your own fun. It,s an interesting concept and I will be keen to see how it develops .
Is the idea of the steps just a way to get the volume up on a narrow board or is it also to get you weight out a bit further ?
forgot to mention. 230cm would be my ideal length on a board. i've had 220-245 boards.
the 220 are a little on the short side for gybing. 245 the nose can be to big.
