Would there be much speed difference between a polyester speed board and a 100% carbon speed board?
There is a big price difference $1395 to $2895 would a carbon version be $1500 faster?
I'm surprised anybody's making polyester speed boards these days?
I don't even know anybody still making polyester wave boards.
I am going to get one to test out and see how it goes. XST 80 Length 7'9”/236cm Width 20.75”/53cm Volume 80L
I don't see there being much weight difference it will come down to stiffness. But a softer ride might be faster over chop.
There is a topic at the moment in Windsurfing General - Is windsurfing popularity still declining? The feeling here is that gear is getting too expensive and too technical, so for a board that is probably about 95% of the performance of carbon for half the cost that will give the same amount of fun, I say go for it.
Not at all.
The only reason I don't have polyester speed boards anymore is that the mould for the blanks has been destroyed and we can't get suitable blanks anymore.
For a board such as you describe, there are actually advantages. The slightly 'damper' ride of a polyester board eats up chop much better than stiff carbon boards which rattle your fillings out. It is interesting that most Carbon Art brand speed board actually have only a small proportion of carbon fiber in them, and to me that is an advantage.
In a small speed board weight is not an issue and lighter is not faster. We have seen people experimenting with actually adding lead weights to speed boards with favorable results!
up until about 2006 I was regularly using a couple of 47-48cm wide polyester speed boards with great success. I have a 44+ Knots peak on one of them! I was also using a 21" wide slalom and it is still the fastest board on choppy water that I have ever had.
The biggest problem I had with my polyester boards is the long term stability of the rocker shape. I re-faired to rocker of my 47 speed board a couple of times after it developed slight negative tail rocker due to warping. (This can happen to epoxy boards as well though).
I eventually ripped the US type fin box out of the slalom board which ended its life. If it had a Tuttle box it might still be alive.
If you know a source of quality polyester blanks suitable size for speed boards I would be most interested. I recon I could still build a polyester speed board for about a third the cost of an epoxy in about a quarter of the time. I have a few pretty radical ideas I would like to try but I will never do it in Epoxy. Too much trouble and mucking around.
I will be getting the board at the end of the month so all will be revealed then. Will post the pictures.
Having a look at you board it is almost the same as one I have just finished out of wood. Once your poly board is done could you post the weight for a comparison. This is the dimensions for the frame with the wood being 6 mm on top of this. The weight ended up at just over 7.5 kg without the foot straps.
That is the fourth wood one so far Keef.
This is the 1st one. It was built with bits that were kept over the years.
The 2nd one I didn't pay enough attention to weight. Although it sails ok, it is just a bit too heavy.
This one is a 43 cm board. Sailboards plane using dynamic pressure (equal & opposite forces ). On this I wanted to see if it is possible to use static pressure ( like an aeroplane wing) to keep it up on top of the water. To achieve this I put a 1/2" concave on the back 1/3 of the bottom. It is hard to say if it has an effect or not, but the board seems to get up on the plane easily for a board of this volume. It might work better on a formula board, but I will leave that for someone else to experiment with. Maybe Starboard will do this and claim another windsurfing invention.
The blanks are polyurethane.
Unlike styrene foam, they aren't troubled by polyester/vinyl resin.
But they can still be made with epoxy and carbon.
They may be using super super light urethane.
Stonesurf at Geraldton does this because he's allergic to epoxy. (I think he convinced Burford of the need to make these blanks)
And unlike OES I don't think he uses a stringer.
Great idea actually, you get a sealed foam, and strong sandwich construction, no vents needed.
The only problem is as sailquick said, the blanks aren't even density, softer in the middle harder near the skin. Means it's not a good idea to deviate too far from the blank's shape.
It has a stringer as you can see from the above pics. I have no delusions about it being heavier than a carbon board but then it is $1800 cheaper. I think it is going to end up working well and you can almost buy 2 for the price of a full carbon one.
problem with PU is that it has no memory, and over time it loses its shape easily.
Pounding through chop the foam is compressed and it permanently collapses a bit with each bit of chop.
A board made with EPS core holds its shape better because the shape is significantly defined by the outer PVC shell, and the blank is able to be compressed without losing its shape, so under impact, the shape returns to original.
Over time the EPS boards will lose their shape, but not as quicky as a urethane board.
Also the urethane boards have much more damping. Can be nice on a speed board, but I find that using glass on a EPS board works nice too. Full carbon boards are a waste of carbon and your knees.