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Fitting a tuttle fin into a deep tuttle box

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Created by eckas > 9 months ago, 13 Jul 2017
eckas
NSW, 323 posts
13 Jul 2017 10:20PM
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Looking for some help/advice.

I have a new tuttle box fin that I want to fit into a board with a deep-tuttle box. My understanding of the theory is that the deep-tuttle box is compatible with both tuttle and deep-tuttle fins. However, in reality, a tuttle fin will only every be held in position within a deep-tuttle box by being wedged into the taper of the box, exerting huge forces on either end of the fin box - a disaster waiting to happen in my opinion. On the other hand, a deep tuttle fin fills the box completely, allowing it to be held by a much safer and more secure clamping force between the bottom of the box and the top of the fin.

It seems that a simple solution is a spacer to fill in the void otherwise create by a tuttle fin in a deep-tuttle box. It will need holes to allow the fin bolts to reach through to the tuttle fin. Does such an accessory exist or am I going to have to make one? Any other solutions or tips on making a spacer? I don't want anything permanent filling the box - on other occasions I will still want to fit deep tuttle fins in the box so I'll need to ensure the spacer cannot become permanently wedged in the box.

Thanks...Eckers.

elmo
WA, 8868 posts
13 Jul 2017 8:25PM
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Yep all you need is longer screws.

I wouldn't worry about the fin not touching the bottom of the box as a TB shouldn't bottom out standard Tuttle box either

Subsonic
WA, 3354 posts
13 Jul 2017 8:41PM
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As the muppet says, the fin'll work fine without a spacer and not break anything. I got bored one weekend and made a spacer out of some kneadit putty, so the fin sits exactly flush in the box. They do tend to get pulled into the box a bit, if the fit isn't exact

I've also seen them made out of the wife's favourite chopping board.

Ive not seen them available commercially.

eckas
NSW, 323 posts
14 Jul 2017 6:53AM
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Thanks for the thoughts. Upon re-measuring, I concur that fins, both tuttle and deep tuttle don't typically bottom-out in the box. The fit is a bit sloppy at the moment (fore-aft movement of 1/2mm), and I cant afford for the fin to be pulled into the box as it has a trailing edge projection that will knife into the board base if it is pulled inwards. Currently bulking up the back of the tuttle with resin/fibreglass to tighten up the fit, then we'll see if there's a need to get more complex with a spacer.

legless
SA, 852 posts
14 Jul 2017 6:38AM
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Select to expand quote
eckas said..
Thanks for the thoughts. Upon re-measuring, I concur that fins, both tuttle and deep tuttle don't typically bottom-out in the box. The fit is a bit sloppy at the moment (fore-aft movement of 1/2mm), and I cant afford for the fin to be pulled into the box as it has a trailing edge projection that will knife into the board base if it is pulled inwards. Currently bulking up the back of the tuttle with resin/fibreglass to tighten up the fit, then we'll see if there's a need to get more complex with a spacer.


It is better just to use some duct tape on the fin to get a tight fit as then you are not modifying the fin and can easily pull off the tape when using the fin in other boards.

elmo
WA, 8868 posts
14 Jul 2017 5:59AM
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Select to expand quote
eckas said..
Thanks for the thoughts. Upon re-measuring, I concur that fins, both tuttle and deep tuttle don't typically bottom-out in the box. The fit is a bit sloppy at the moment (fore-aft movement of 1/2mm), and I cant afford for the fin to be pulled into the box as it has a trailing edge projection that will knife into the board base if it is pulled inwards. Currently bulking up the back of the tuttle with resin/fibreglass to tighten up the fit, then we'll see if there's a need to get more complex with a spacer.


With a few of my fin box's being power box and next to useless for holding any weed fin over 30cm rigidly (I hate PB it's f'ken useless) I file the bottom of the trailing edge of the weed fin to give 3-4mm of clearance on the board.

Never had any detrimental effects from it and no fin marks on the board if I sail in to shallow

Swindy
WA, 456 posts
14 Jul 2017 7:34AM
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If not using a spacer don't tighten screws to hard because you can split the box. Same if you run aground hard.

joe windsurf
1482 posts
14 Jul 2017 7:42AM
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what happens if you run aground with a deep tuttle ?
hope i didn't just jinx myself
.
the beauty of the PB is : when you hit a rock or run aground, the screw head pops off and the fin comes off
when that happened to me, my fin was a goner, but board was fine !!

Swindy
WA, 456 posts
14 Jul 2017 11:04AM
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joe windsurf said..
what happens if you run aground with a deep tuttle ?
hope i didn't just jinx myself
.
the beauty of the PB is : when you hit a rock or run aground, the screw head pops off and the fin comes off
when that happened to me, my fin was a goner, but board was fine !!


If the thread in the brass inserts doesn't let go all kinds of nasty stuff. With a standard fin in a deep box I would imagine the back of the fin would get rammed into the bottom of the box which is obviously much narrower in length.
Anyone got an old board,fin and big hammer that can simulate hitting a rock at 35+ knots results would be appreciated.

firiebob
WA, 3172 posts
14 Jul 2017 1:52PM
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rogerswin said..

Anyone got an old board,fin and big hammer that can simulate hitting a rock at 35+ knots results would be appreciated.


Hey Roger I've done exactly that but with a new board, 36 knots into a reef bombie, shoved the fin base right into the back of the box Contacted CA and found it was an easy fix, if you ever do the same I'm your man

Imax1
QLD, 4925 posts
14 Jul 2017 6:17PM
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I would presume tuttle and deep tuttle would smash out the same. If anything a tuttle in a deep tuttle box would be less of an explosion.
We need field tests , Sparky ???

Swindy
WA, 456 posts
14 Jul 2017 6:43PM
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firiebob said..

rogerswin said..

Anyone got an old board,fin and big hammer that can simulate hitting a rock at 35+ knots results would be appreciated.



Hey Roger I've done exactly that but with a new board, 36 knots into a reef bombie, shoved the fin base right into the back of the box Contacted CA and found it was an easy fix, if you ever do the same I'm your man

Cheers Bob. If your up north at the time will you come back and fix it for me.

Should be ok though, I use a spacer anyway and I just moulded a second one last weekend.

Man0verBoard
WA, 629 posts
20 Jul 2017 3:10PM
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It really depends on the construction of the box..in terms of damage.
Just FYI...Kinetic boxes are strong...coupled with Tribals Urethane head...the radiused top helps with not fracturing the box plus the Urethane will distort and absorb some energy. Good combo

mistral slalom boards and Wind Tech's have top notch boxes

Mark _australia
WA, 23453 posts
20 Jul 2017 5:46PM
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^^^ Does tribal still use the same barrel nuts? I ask as IMHO if the urethane head distorts and absorbs some energy, then the designed 'barrel nut stripping' may not occur. I would rather that the (seemingly) time proven system of the brass barrel nut being machined with loose tolerances, so the fin bolts strip the thread out easily, is kept.
If that system works just but then you add a different fin head construction in the hope of preventing damage, it may stop the first system from working.
Further, if the head is not rigid, the interference fit taper lock won't be as efficient meaning the bolts are holding more tension.

The point in this thread seems to be will a tuttle fin work in a deep tuttle box without damage? Yeah they will bust out just the same when you hit something as the box taper and interference fit is the same.
However any box can be busted............. or any fin bolt can let go prematurely upon being hit.
I'd say the install is more important, the more d'cell around it the better.

Pimping new Wind Tech again is not so relevant.

gavnwend
WA, 1372 posts
20 Jul 2017 5:53PM
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Select to expand quote
Man0verBoard said..
It really depends on the construction of the box..in terms of damage.
Just FYI...Kinetic boxes are strong...coupled with Tribals Urethane head...the radiused top helps with not fracturing the box plus the Urethane will distort and absorb some energy. Good combo

mistral slalom boards and Wind Tech's have top notch boxes



Thats interisting to know. I got a mistral slalom board slowie design. I want to strap a tuttle head foil on it.spacer on top with stronger bolts. Mistral & windtec have stronger construction fin boxes.



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"Fitting a tuttle fin into a deep tuttle box" started by eckas