first attempt at uploading to or from YouTube its taken a while but finally got there , when I get around too getting the board up on youtube ill do a post on how too customize a board and make the fin

id be afraid of getting cut by it . keen to hear how it sails though

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Simon100 said...
id be afraid of getting cut by it . keen to hear how it sails though

simon100 as long as your not a kiter you don't have to worry
made the board and fin for LG that didn't eventuate but knocked up a tidy 36.8 on the weekend gpsteamchallenge.com.au/sailor_session/show?date=2013-03-17&team=34

slowly getting a vid together as well as doing another fin
hopefully I can get some feedback between now and next janurary from some of the dedicated fin guys and see what we can come up with for LG


the fin is what you mite say a hybrid ,so in between a C3 slingshot aand MFC DELTA, the difference is , the cord isn't as long as the MFC and has less rake=47deg, the foil is similar to the C3 with a thicker foil at the base for 1/3 then drops away so there is about 2mm difference too the base to the tip, where as the MFC is flat from the base to the tip
the idea of the stainless leading edge is, carbon is very soft and will sand easy, as for stainless you cant sand it , you can file but cant sand
the stainless is layed in with 20 strands of woven roving's, the roving's are extremely stiff and have to be soaked overnight to soften them up, the rest of the core is 205gram uni carbon ( $22mt)
the fin it self has a very lively feel, the good thing about these type of fins is they have a big sail range , its no problem to be powered up with a 6.2 and drop down to a 4.6 on the same fin
see what I can come up with after Easter and hopefully add to the post

What do you soak the carbon rovings in to make them soft?

the core is vinyl ester so + 10% styrene, with epoxy you can use either styrene or acetone

Hope your experience with stainless leading edges is better than mine keef!

I tried on several fins, but after a while most of them delamned. Not sure if it's the different expansion rate between carbon and stainless or what, but I've given up on the idea. Although you're right about the wear properties, it's fantastic!

Lake George weed isn't abrasive, (unlike our estuary and Albany harbour), all I noticed after 2 weeks sailing was a slight polish. Even some of the mud there can be sailed thru without any damage, but there are spots with sand/shells in it that does abrade fins.

Radical looking board mate, how fast have you gone on that?

mike I have some pics coming up on the layup, basically the stainless is 20mm wide x 1.5ml with holes drilled every 20 to 25ml then layed up in the roving's and uni carbon with vinyl ester, if it does delam it can only lift 10mm into the leading edge because of the drill holes
I know the weed your talking about we have a lake here with the same weed, last year I was getting close to 38 with a 21 slingshot 30deg
ive also got some pics on how to lay the board up, its an old slalom I modified along the lines of the MXR only more radical it's 280mm at the first cutout , I think 580 from the tail , had it to 36.8 in a southerly gpsteamchallenge.com.au/sailor_session/show?date=2013-03-17&team=34 , even knocked Ado off his perch, he was here in January and set top speed of close to 36nts that was n/e

Yes, those holes may do the trick, (hope so), the stainless I had wasn't that wide.
Sounds like the board works well.

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decrepit said...
Yes, those holes may do the trick, (hope so), the stainless I had wasn't that wide.
Sounds like the board works well.

mike remember im laying the stainless in-between two pieces of ply the same as we were talking about 12 months ago
well you know what its like trying to get a narrow speed board going, trying to dig the fin off the bottom, then swimming the thing waiting to get a gust so you can get back for your slalom board then too bugged to sail it, well it aint going to happen with this one
the southerly is a bit sloppy at sanctuary point and only a short speed run , but seeing the board is on top of the water it only needs a sniff of wind and its on the tail like a rocket ship

Yep, I'll be getting my channelled board for our gusty winter winds, small sinkers are a real pain in up and down stuff

I just noticed www.andersbq.com/2013/03/obsessed-with-fins.html
c3's proto weed's leading edge is 45deg the trailing edge is 25 deg and 22 to 23cm
just for interest my fin's leading edge is 45deg, trailing edge 10deg 19cm (not 18) it would be interesting to see his report
what ever the outcome ,the fins are going to be over $200 and there going to be heavy (that's if there anything like the slingshots) the fin in the pic isn't the one in mention but very close

I just noticed www.andersbq.com/2013/03/obsessed-with-fins.html
c3's proto weed's leading edge is 45deg the trailing edge is 25 deg and 22 to 23cm
just for interest my fin's leading edge is 45deg, trailing edge 10deg 19cm (not 18) it would be interesting to see his report
what ever the outcome ,the fins are going to be over $200 and there going to be heavy (that's if there anything like the slingshots) the fin in the pic isn't the one in mention but very close

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keef said...
I just noticed www.andersbq.com/2013/03/obsessed-with-fins.html
c3's proto weed's leading edge is 45deg the trailing edge is 25 deg and 22 to 23cm
just for interest my fin's leading edge is 45deg, trailing edge 10deg 19cm (not 18) it would be interesting to see his report
what ever the outcome ,the fins are going to be over $200 and there going to be heavy (that's if there anything like the slingshots) the fin in the pic isn't the one in mention but very close

the C3 weed proto on Anders site is actually 48deg in the leading edge...
it's 22cm deep and has roughly the power of a 32cm slalom fin when powered up.
fins with that much rake never have the same feel and/or power when trying to get going or underpowered.

Boogie

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C3 said...

keef said...
I just noticed www.andersbq.com/2013/03/obsessed-with-fins.html

the C3 weed proto on Anders site is actually 48deg in the leading edge...
it's 22cm deep and has roughly the power of a 32cm slalom fin when powered up.
fins with that much rake never have the same feel and/or power when trying to get going or underpowered.

Boogie

I hear what your saying Boogie i love your fins that's the reason why I have gone for a similar foil as your C3 slingshot and the more vertical trailing edge ,ive been playing with the mfc delta's and lifting the rake but with the flatter foils the fins are still way too loose
i'm getting some stuff together too post , your going to have a chuckle but its all in fun so keep posted as I would like to hear your input , just keep it in mind that these fin's are an inspiration from your c3's

Keef, you need to revive the swinging fin. A good bearing will be essential to get around the sticking issue with swinging centre boards. You could crank it right back to 55 to get started in thick weed, back to 38 as you head to the shallows at speed, then let it come back by itself as it scrapes the bottom like an inverted Melbourne tram. No tip vortices, that's got to be good. Call it the "tram fin".

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Ian K said...
Keef, you need to revive the swinging fin. A good bearing will be essential to get around the sticking issue with swinging centre boards. You could crank it right back to 55 to get started in thick weed, back to 38 as you head to the shallows at speed, then let it come back by itself as it scrapes the bottom like an inverted Melbourne tram. No tip vortices, that's got to be good. Call it the "tram fin".

sounds great ian, but ill have to stick it on the backburner until ive got this project done, if you can come up with a few ideas, like when you think of something just jot it down so you don't for get .
like now that your on the boil "wow" tram fin, I wish I had have thought of that I like the idea of cranken it back to 55 in that heavy stuff and watching all the sparks fly off the weed ,then back to 38, man that new helmet is going to look fast
ian it sounds like your cantilever fin has had a rebirthing

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C3 said...



the C3 weed proto on Anders site is actually 48deg in the leading edge...
it's 22cm deep and has roughly the power of a 32cm slalom fin when powered up.
fins with that much rake never have the same feel and/or power when trying to get going or underpowered.

Boogie

for everyone out there who hasn't gone to sleep waiting for my post on how to make the fin, i have decided to catch the next tram to GENERAL i have spent a lot of wasted hr's trying to edit the how too's , i started with my new gopro but was having problems and now it's glued to the bench, so had to resort back to my Olympus, looks like everyone on this site has gone to sleep

when i started this post ,there wasn't anyone making the wider shorter profiled 45+deg weed fins, so i decided to show you guys how to make one, that's until i noticed Anders c3's proto 47deg
boogie mentioned as above( fins with that much rake never have the same feel and/or power when trying to get going or underpowered.), i'm going to have to disagree to a certain extent, the thing you notice with these fins is how controlled the board is in overpowering conditions ,with speed, slalom and race fins they can be totally uncontrollable when over powered

i'm not sure if c3 wanted the publicity at the moment about the proto, but i can see these fins also replacing the free ride
soooooo long gps speed sleeper's , my tram is about to pull into general to see if anyone is awake, for the guys that are interested have a look in general it will be up in a few days
"edit" but ill be back to show you guys how to do a mod on your old slalom

ok ive changed my mind ill an each way bet and have it on both pages

What chord thickness ratio are you using Keef?
I've found that even though the shallow water weedies work, they are a tad slow. Owing to this I've made another 27 with a chord ratio of 7%. I was using 8-8.5% but I'm hoping to reduce the drag and think that with the flow extended over a larger distance I can drop the ratio?! R&D, gotta love it. (should be T&E).

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pepe47 said...
What chord thickness ratio are you using Keef?
I've found that even though the shallow water weedies work, they are a tad slow. Owing to this I've made another 27 with a chord ratio of 7%. I was using 8-8.5% but I'm hoping to reduce the drag and think that with the flow extended over a larger distance I can drop the ratio?! R&D, gotta love it. (should be T&E).

pepe , ill have to agree and disagree and that depends on what board your rideing , a weed fin isn't as fast as a slalom fin in a slalom board but there a hell of a lot better behaved than a slalom, a weed fin in a slalom board the board will ride flatter and at the boards max speed, put a weed fin in a speed board and the board will sail off the fin, you will have more control than a slalom fin, the fin wont get overpowered and you wont get the backend wobbles and the fin trying to launch you out of the water like a rocket ship
the fin in the photo is 17.5, mudskipper stuck it in his custom slalom with a 6.7arotech in some decent chop , his first sail in two years and clocked up
gpsteamchallenge.com.au/sailor/view/3977
the first time I used the fin in the video I clocked up 36.84 on my customSL, that was a southerly and most of the sailing was in lumpy swell with a short weed speed strip

Im sorry but I wouldn't have a clue on how too work out the %'s , the cord length is 22cmX18cm, the leading edge is 47deg,trailing edge is 10deg
the foil thickness is 12mm 8.5cm from the front tip of the fin
I think the foil is a touch forward than your normal maybe you can work the % out from there

Well, my maths isn't all that crash hot but I think that's 6.1%. If that's so, then it explains why you don't have the drag that I have with 8.5. Gonna have to send the bigger fin to my jenny craig sander!!

I've just upped my 6.5% 55deg weedy to 9%, it was very slippery but didn't have much lift.
Have I gone too far?
Guess I'll have to find out.

Take a little off at a time Pepe, then you have a better chance of finding the sweet spot.

I think you're right Decrep, definitely paying my share of the carbon tax.
Hope the carbon powder is good for the lawn

pepe these carbon fins are about 80% carbon so there extremely stiff, by the time the fin is foiled there isn't a lot of ply left , you can go really thin where you want
if you have a close look at the video as long as you keep everything strait it's not hard
there aren't any of these fins on the market as yet, so if anyone planning on boggy lake next year its worth a try
I have a few fin projects coming up that ill tacking onto this thread, ill be putting them to the test at illawarra in a few months and gearing up for boggy next year

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decrepit said...
I've just upped my 6.5% 55deg weedy to 9%, it was very slippery but didn't have much lift.
Have I gone too far?
Guess I'll have to find out.

Take a little off at a time Pepe, then you have a better chance of finding the sweet spot.

mike I think the reason why these fins have so much lift is ( 1) the trailing edge is 10% so the center of effort is like a c3 slingshot,(2) the foil is like a slingshot, nice and full at the base and about a 5mm clearance at the tip

have a look at the vid and you will notice I basically made the foil from wheeling chop over the whole fin
the best thing pepe could do is take the foil down to 6.1% and if he needs to go thicker he can wheel in some chop, when you get the nack you can move the fibers where ever you want them
when im foiling the fins I use a hacksaw blade and scrape , the fillings are nowhere as fine as sanding, just needs a light sand at the finnish

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pepe47 said...
I think you're right Decrep, definitely paying my share of the carbon tax.
Hope the carbon powder is good for the lawn

the best thing to do is save all your fillings and add them to the resin, when your boxing or need some really tough filler , the fillings have already been cured so when you add resin to the fillings again , it gives a second cure (compound cure) eliminates the chance of the box cracking like it can with just bog

finally finished the fin, had several change of plans after viewing boogies 25cm weedy, also decided to do a assy for primbee, not that I know anything about assy's I have to be carefull what I say for petermac
I guess the object is not for you to copy what im doing or take anything I say as gospel, the whole idea is to show you what you can do with a wheel
one thing you can take as "quote" gospel there isn't any glassing job you cant do with a wheel, but there's a lot of jobs you cant do whithout a wheel

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decrepit said...
I've just upped my 6.5% 55deg weedy to 9%, it was very slippery but didn't have much lift.
Have I gone too far?
Guess I'll have to find out.

Take a little off at a time Pepe, then you have a better chance of finding the sweet spot.

decrepit I have beefed the foils up with some blade putty and bog spay and made them a bit thicker , then made some molds, after they come out of the mold ill remove the bog, and bring the fins back to original, and see what the difference is, at the end of the day ill have two different fins, one thick and one thin, hopefully rather than changing fins with a longer length I can use a fuller foil
just in case you have missed something theres two separate videos , ive tried to download a few times but keeps comeing up as two tracks

Your getting fancy with your movie making but not everyone has those 3D glasses yet. Can I borrow yours to view the vid properly in stereo?

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KA360 said...
Your getting fancy with your movie making but not everyone has those 3D glasses yet. Can I borrow yours to view the vid properly in stereo?

is that what it is , i made a few changes and uploaded 5 times to youtube , ill be around on the weekend to pick up that old apple your not using