Just started having some fun blasting across the ocean swells and noticed my current fin ( a 35 cm JP Carve) wants to blow out a fair bit. At best it gets air and drifts sideways then if I'm lucky recovers, at worst you do a 180 and end up in a mangled heap. So, is this pilot error or do I need a specific fin for blating across lumpy ocean swells?

The outfit- 101 JP FSW with 6 mtr Hot Sail Maui (freeride style).

Cheers for any info.

I'd suggest that a 35cm fin for that board and that sail should be fine and it could be your stance that might use a little tuning.

If you're spinning out a lot, it could be that you are exerting too much weight and force through your back foot and trying to sail too much like a slalom sailor, pushing hard against the fin.

Others will be able to explain this better than I, but try to bring your weight forward and off the fin a little - hanging down through your harness to put your weight through the mast foot more (mast foot pressure) may assist and will also potentially get you planing earlier.

The other technique that could be looked at is varying your stance as you go over the top of a swell. If you're catching even the tiniest bit of air or even going light (image a car going over a bridge) then the fin can spin out. If you learn to anticipate this and to take the pressure off the fin as you go over the top, it will help to prevent spinout.

My 2cents.

fin should be okay, try setting your boom a bit higher

The boys are spot on, technique may need an adjust.

BUT if it is comfy planing wind, that fin is a little large.

I use a FSW 100 or 105 - with a 6m, comfy planing, a 28cm freestylewave fin is spot on. If I want it looser and willing to sacrifice some upwind ability and need to think about back foot pressue (or lack thereof!) a lot, then maybe down to a 26-27cm wave fin.

The effect of too big a fin is usually the opposite of spin out like you are describing (the fin "blowing out" as in moving to leeward at the top of a swell or landing??)
Usually too big a fin results in railing up to windward etc.
But when u r majorrrlly out of control due to too big a fin or sail, the end result can feel a bit different as it is all over the place and hard to pick which bit went which way just before the huge stack.

Describe the feeling more...?

Excellent info guys!

Flicky, you touched on some exact things when the fin goes all loose on me. One is when I'm trying to gain ground up wind and driving (probably too hard) off the back foot. Combine this with a 6 ft crest doing 25 knots and things go wonky real quick! Definitly hasn't happend going down wind standing more flat footed. Sounds like pilot error

Sean, took me 3 months to get a comfy boom height, so I ain't changin' it...lol

Mark, you said, "I use a FSW 100 or 105 - with a 6m, comfy planing, a 28cm freestylewave fin is spot on". I was using the 28 cm FSW fin that came with the board, and it's great for wave riding and going fast in a straight line- but scary for me when turning fast in swell. Again, it's probably me pushing the back foot too hard. That's why I tried the 35 cm fin today. Funny thing was, the bigger fin feels looser on the waves. I could get the tail to slide at will, yet the 25 FSW fin sticks like glue? Rattled about that.

I don't know how wear and tear can effect a fin, but the 35 cm job is a little sand blasted from running up into the shallows. Kinda square on the bottom edge. Would that make any huge difference?

Are you using 3 or 4 footstraps????

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jh2703 said...
Are you using 3 or 4 footstraps????

Three. The front straps are set close to the centre line.

^^^ OK That takes that out of the mix, Some people run 4 straps on these boards for ocean blasting and being out on the rail will put extra pressure on the fin.

You just need to get use to the smaller fin, If your not going to jump the swell just make sure you really bend your knees as you go over the top....Use your back leg like a shock absorber. This will unload the fin as you reach the top, As you clear the top start to straighten your legs out again to your normal sailing position. Leaning forward will take the pressure of your back foot and curling your toes up on the front and back foot will help rail the board up and gain a bit extra grip for going up wind.

My method, May not work for you???

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PhilSWR said...
I don't know how wear and tear can effect a fin, but the 35 cm job is a little sand blasted from running up into the shallows. Kinda square on the bottom edge. Would that make any huge difference?

That alone could be enough.

Get a brand new fin and hit it once on a rock so it has a rough chunk in the lower leading edge. That will be enough to make it misbehave badly when close to the limit. (Or even well before that!)

Pic?

Here's a pic of the fin. Beach sand hasn't been kind to it

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jh2703 said...
^^^ OK That takes that out of the mix, Some people run 4 straps on these boards for ocean blasting and being out on the rail will put extra pressure on the fin.

You just need to get use to the smaller fin, If your not going to jump the swell just make sure you really bend your knees as you go over the top....Use your back leg like a shock absorber. This will unload the fin as you reach the top, As you clear the top start to straighten your legs out again to your normal sailing position. Leaning forward will take the pressure of your back foot and curling your toes up on the front and back foot will help rail the board up and gain a bit extra grip for going up wind.

My method, May not work for you???

Thanks Jason for the tips. I have been trying to jump the swells (with mixed results) but the tail sliding / loosing grip stuff has usually occured when driving hard up-wind.

So I'm not the best person to advise about this - I normally sail sub-20cm fins, but here's something to think about.

When sailing upwind I use the rail of the board a lot, and the fin very little in order to get me upwind.

On a 101 FSW I think the same technique is applicable.

My stance:
Hanging down through the harness
Back leg pretty straight
front leg bent, knee pointing forwards in the direction of travel
hips twisted forwards facing the direction of travel

This allows me to use the rail enough (i.e. the board is leaning ever so slightly towards me, which allows the windward rail to be in the water a bit more to provide more lateral resistance) to take the pressure off the fin and drive upwind on a 100 litre FS board with a little fin and a 5.7m sail.

Give it a shot - it's a bit difficult to explain but it may assist.

Main culprit could be too much back foot pressure as many hinted, though another reason for the fin letting go could be rig balance and settings.

Try moving your harness lines slightly back on the boom coz if they're too far forward then this can result in insufficient mast foot pressure which may cause spin out

Also, where do you have the mast foot positioned with the 6m? I've found that if my mast foot is further back than the 'sweet spot' position (for blasting) then this can upset the rig balance and make it harder to go upwind, particularly in choppy water (I found that moving the mast foot forward on my JP FSW really improves both general blasting and upwind performance). Try moving mast foot further forward, say around 2cm at a time then take kit out for a sail and see what happens (obviously move it back if things get worse!). Also try this using the smaller fin.

Have you sailed the same gear on flatter water previously and if so, did it feel any different?

Thanks Flicky, I'll try a few of ya tips you mentioned and see if it makes any difference.

Gazman, I've just the mast set in the track right in the middle. No reason why, that's just where it is. I'll bump it forward and see how it feels. I've used both fins (26 cm and the 35 cm) on flat water, and the 35 definitly holds in better. The 25 cm gets a little loose around 25 knots. Beyond than it's scary. Again, no doubt it's pilot error. The best fin I have for grip and control is my weed fin- only used it in the lakes though. Basically, I think more TOW is in order!

Cheers for all ya help.