I am just about to put an order in for some Black Project WEEDspeed fins, I have never used weed fins before and need to know if they are comparable in terms of size choice to normal slalom fins?
The pic on the site (blackprojecthawaii.com/ scroll down, the page isnt updated yet though) shows more area, especially at the base so I am guessing slightly smaller fin on the same sail.
I need them for the BSA slalom and know you guys use them a lot on your lakes. I will have sails from 8.8 - 8.0 - 7.3 - 6.6 - 6.0 - 5.5(dont think I will race in slalom for my first season if its 5.5 weather though!). The fins come in sizes 42,38,34,31,28. Ideally I only want to get 2, so which 2, but if I have to stretch to 3 then which 3. I have a full quiver of slalom and near full quiver of speed fins, but have read reports from previous years where the earlier events are plagued with weed.........
Thanks in advance
If you want them for slalom rather than speed then you will need to go bigger as the crosswind performance of a weedy is considerably less than a pointer unless well powered up and slower to accelerate out of the gybe. If I were going for two with those size sails I would go 42 ( for 8.8, 8 and a big board) and 31 (for 7.3, 6,6 and might be a bit big for 6 / 5.5 but I am assuming you are talking ocean rather than flat water).
The Mandurah mob started with 36 and 31 JP weedies which cover most conditions but they don't use as big sails as you.
Personally I have used a 40 Leading Edge weedy with a 122 iso and Loft Blade 7m and found it a good fin up to about 18 knots. All my other weedies are smaller with my 24 a favourite on 6.3 and less for speed sailing on flat water.
If you can go 3 fins 42,34,28 IMO
The sizes they have given the Black Project Weed Speed fins relate to what they reckon would perform the same as the equivalent size Type R so in theory select the fins based on what size Type R fins you would be using. They are looking into creating some smaller ones maybe a 25 and a 22 for speed boards.
They look nice, but I'm not sure, they seem like straight G10 to me.
The shorter fins may be OK, but unless they are quite thick, longer weedies need carbon in them to be stiff enough.
I got Black Projects to make me a weed fin about 12 months ago stating that the percentage along the flow line needed to be about 9 to 10. However the fin came back too flexy for my liking. It was around 9 percent, but not along the flow line. More like along the flow line if the fin was upright, then canted over to 40 degrees. Attached is the original drawing supplied to them around this time last year, seems to me that they thought it might work. 
I should have started with "now don't get me started". This is the same fin after more than 10 hours work on it... Because the fin was too flexy, the only solution I could come up with was to laminate carbon on to it. Introducing Mr hacksaw and Mr belt sander, a couple of mates of mine. Not a cheap solution! (timewise and cost). But the fin is now fast and rigid. Also able to withstand a fair amount of abuse.
I've needed to do this to my larger fins only as the smaller ones are inherantly more rigid. (the smaller you go the more rigid etc)
Here's a test, go out and grab your favourite weed fin, bend it over your knee and see how much flex it has....defence rests your honour.
.....but I guess you like most people just like to see the worst in everyone.
??????
The topic was about weed fins. I was commenting on that. As noted here by yourself and others tip flex on pointers is not a bad thing but but not really relevant. My other comment was just a suggestion not a critism and I'm a bit surprised you took it so personally. I think most people would like to know if someone offering an opinion about something has a vested interest in that something.
Thanks to all of you, no need for argument allthough I can understand why people get defensive nowadays after recieving some flack myself for 'pimping'.
Most windsurfers will help each other, obviously some will have a vested interest in certain brands, either through plain old brand loyalty from personal choice, or through trying to make a living in this world where everyone has got used to getting things for free. I feel lucky that I chose to change my quiver over to Black Projects back in October after testing some Exocets that came with a quiver of type R's. It wasnt until christmas day that I recieved an invite to become a team rider (second best Christmas present! Best was a Neil Pryde race bag :-D), I had already bought a half quiver by then. I know Legless is the importer over there, as he has been very helpful in the past and told me this in other threads. Shops over here wont stock specialist fins, the only slalom you will find are the odd drake and maybe a prolimit slalom-esque style fin so I guess its a similar situation over there, everyone needs to try their best to make a living, and some importers choose their products for a good reson, they believe in them!
I need them for the slalom series (not that it will make much of a difference, I have never raced before!), and I suspect I wont use the 42 very often. I like the idea of getting the 42 34 28 which allows me to trial them across the range. I am lucky at my home spot that we hardly ever get weed, and where we do often its too shallow to risk sailing over, as it is full of rocks as well. The only bad time for weed here is in the mid spring when a lot of the old weed detatches from the rocks up in a lagoon that floods into the harbour. So I will either go for the 3 as stated or maybe just the 38 - 31 and save a bit of money for now.
Thanks for all your help.
I think it should also be noted there are different grades of G10, I cannot tell you the specifics but I learned this from a certain West Aussie speedsailor also well known for his fin design and making. My attempts at googling G10 do not yield many results of value.
I have two different 46cm weedys from two different fin makers with Maui in their name and one is a LOT stiffer than the other one and when standing up against me and my 8.6 the stiffer one performs far better.
We havent had any wind since I posted that, have you seen where the Portland Pirates are this month on the GTC? Worst month since I joined. I also havent got the Weed fins yet
Yes the trouble is that when a weedie flexes it loses angle of attack towards
the tip. An upright fin can flex without losing angle of attack. I think I've even read that they can bias the fibres in some upright formula fins such that they increase angle of attack with flex.
I've got a couple of Select weedies. They had all the issues you hear about in weedies, but with one and a third layers of carbon they are much, much better.
I worried that if the layer of carbon stopped abruptly at the base there would be localised discontinuity of flex and not the maximum stiffness. So when I laminated with carbon I routed channels in each side of the base so a supplementary pair of 40 mm carbon strips could run continuously from the wide section of the foil into the base. I then back-filled the base to it's original shape.
I spent a lot of time thinking about the best angle of laying the fibres so that there would be a twist within the remaining flex that would minimise loss of angle of attack at the tip. I couldn't get my head around a solution so just ran the fibres straight down the fin's long axis.
Sounds about right Ian, I normally remove all the base around the thickest part of the fin, (that's where the load is). Running the uni slightly from the back of the fin at the base to the front of the fin at the tip will allow the fin to flex off, from the front of the fin at the base to the back of the fin at the tip will cause it to flex on.
This is probably what you want with a weedy, (my head can no longer do dynamic 3d modelling,
. Just bent a bit of card at 45deg, and flexing on, is the go), but overdoing it would lead to instability.
Must give it a go next time I carbon a weedy.
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