I think you actually cut them off a couple of dolphins and glued them into a fin base


Good job..... have you stopped itching yet he he

Mark _australia said...

Good job..... have you stopped itching yet he he

After working as a boat builder for a while it takes a lot to get me itching. the worst is carbon fibre dust that was used with epoxy.

Have you used any of them yet?

What do you use to draw your smooth curves?

Some nice looking fins Bertie - good work - will be interesting to hear how they go!

I made one from last years JP Freetyle fin - pictured here next to the 2010 JP Freestyle fin that came with my 98L JP Freestyle board this year.

Works unbelievably well - sooo much better for freestyle - and not much impact to normal sailing!

I guess the problem with twin fin freestyles is u need to find a pair of fins to cut up.. Is there an evil twin without any fins or can u buy them? why not cut up the standard twister fins? (I dont think tabou seriously expects anyone to sail with unmodified standard fins anyway!)

here is one i made for Mitch.
154mm raked "pengo"

I had a go of the 1st fin in the line up with the 3 blue fins. Impressed.
Not sure how big it is but the size was pretty spot on. You could get up wind pretty easily and you could still get it to pop out and slide pretty easily. It didn't feel draggy like a lot of hand shaped freestyle fins do.
Over all I think that one is a success. Looking forward to trying out some of the others now.
Nice work.

they look really good, seems like you are a big fan of the maui ultra fin style profile. looks like you are removing a lot of material, how are you doing that whilst maintaining an accurate cross-sectional profile? what tools are you using?

I have a spare fin that i'm looking at making into a supershort freestyle fin, sounds like it will take a lot of time and patience

swoosh said...

they look really good, seems like you are a big fan of the maui ultra fin style profile. looks like you are removing a lot of material, how are you doing that whilst maintaining an accurate cross-sectional profile? what tools are you using?

I have a spare fin that i'm looking at making into a supershort freestyle fin, sounds like it will take a lot of time and patience

Not sure of the magic tricks Bertie uses but the way I did mine above was with an angle grinder.

Cut the initial shape. then draw a line down the middle of the leading (& trailing) edge of the fin where you've cut it. Also draw a line a few CMs in from the edge on both sides. then use an angle grinder to take the edge off the cut making sure you don't grind past the lines. You don't want the leading edge to be sharp so don't grind too much fin off. then just use wet & dry sand paper to finish off - with progressively smaller grit.

It about an hour in total and looked like a new fin once I was done. It works super well for freestyle - and hasn't lost much in the way of speed, early planning and upwind performance.

Good luck!

Bertie said...

Here is what the concrete wave now looks like:

its supposed to be a weed freestyle if ya couldnt tell. But i'm not a fan of 45 degree fins.


As to shaping its lots of angle grinder both cutoff wheel and sanding pad. then orbital sander for fine tuning. The old sanding block still get a fair bit of use to clean up the outline and tidy up the leading and trailing edges.

As good as that looks, i dont think it will work, the the same reason why you cant just put a twin fin wave fin in your freestyle board.


Because that fin as so much rake, when you slide backwards it will catch and throw you off.

But then again, Golito the world #1 freestyler, gets his stock MFC fins and cuts off the bottom and uses it, no shaping, no sanding just a angle grinder and off he goes!

Gestalt said...

i thought the rake and throwing off thing was more about the trailing edge rake and not the leading edge?

i think i read that somewhere. not sure.

Yeh, you could be right. Im just not too convinced on the "weed freestyle fin"

the reason for the weed freestyle fin is coz some of the best freestyle spots in WA are much easier to sail with a fin that sheds weed. I have made a few rough ones before for people but think there is a better solution out there.

The trailing edge rake angle is intentionally very close to vertical. I doubt it would catch like a traditional wave fin does when going backwards.
The leading edge progressively increases in rake angle as you get to the tip, for weed shedding.
Squarish and quite thin tip for reduced induced drag.
Fairly fat profile coz FS boards are sailed slow (relatively speaking) and to generate lots of lift at low speeds.

All the fins with the narrow tip outline are to reduce tip surface area to prevent catching whilst spinning and backwards sliding which i can see as a issue at times with a "Spud" shape fin.

All fins were claimed from the bargain bin at windsurfing perth. At present i dont have a powerbox board, so this as an exercise had been about killing time doing the kind of stuff i enjoy most.

I am starting to look for more fins to play with. If you have some damaged twinzer fins(US box) or power box fins where the base is still OK, i'd love to take them off your hands or reshape them for ya. PM me if you have some. Cheers

ah yeah, sounds about right. I was thinking of attacking the old fin i got with a flapdisc to remove bulk material then hand sanding to finish. might have to see if i can get my hands on a orbital sander to save a little time. I suppose the tricky thing will be to get the fin profile right.

Scully said...

i believe i have that board and fin, did i just buy that? lol

Well it can do a spock so there's no excuces

NotWal said...

Scully said...

i believe i have that board and fin, did i just buy that? lol

Well it can do a spock so there's no excuces

dave we have so far to travel.