smashed my finbox last year, the front screw pulled down and split the box ,the back of the fin smashed the back of the box out, since then i have sleeved all of my boards with some plastic tube and used smaller head screws with nylon washers so if if you hit a rock the screws will shred the tubing, other wise if you use big washers and big head screws you can loose the back of your board , what else does every one else use to stop the damage, eg fast run out tides and coral reefs

I used at one stage some rubber domed seals which were normally used on seeling corugated iron, plastic.

They were about 10mm thick and would hold the fin well normally but under extreme duress they would be able deform enough (about 4mm) to absorb some energy

With my powerbox fins I've found through trial and error that the brass barrel nut will strip if I hit a rock or similar obstacle large enough to rip the fin from the board. This could open up an argument for and against power/tuttle boxes, but ensuring that the fin is secured to the board to the point where the board is going to be damaged just doesn't cut it.
For my money the fin almost has to be "sacrificial" if you're in conditions where fin damage may occur. Each time I find some limestone I just hope the fin has taken the full force of the strike. I certainly won't re-enforce the anchor point of the fin with any washer larger than the stock one.
Also when I rebox any fin I won't use too much re-enforcement around the barrel nut for that purpose.

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elmo said...

I used at one stage some rubber domed seals which were normally used on seeling corugated iron, plastic.

elmo the back black domed washer is off roofing screws they mite be the same as your talking about they are very tough and a really tight fit

That's an interesting rear strap design keef
Pepe47 any more weed fin designs in the pipe line.

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pepe47 said...

With my powerbox fins I've found through trial and error that the brass barrel nut will strip if I hit a rock or similar obstacle large enough to rip the fin from the board. This could open up an argument for and against power/tuttle boxes, but ensuring that the fin is secured to the board to the point where the board is going to be damaged just doesn't cut it.
For my money the fin almost has to be "sacrificial" if you're in conditions where fin damage may occur. Each time I find some limestone I just hope the fin has taken the full force of the strike. I certainly won't re-enforce the anchor point of the fin with any washer larger than the stock one.
Also when I rebox any fin I won't use too much re-enforcement around the barrel nut for that purpose.

ill have to agree pepe47, i just reboxed a tabou power box , the post were you screw the fin in snapped and the box just fell out of the board, the box wasnt resined in , it was held in with expanding urathane foam

aus718 i dont have any weed fins the closest ive got is a slingshot 21 but i am plannining on getting one
yep the back strap is reall comfy and you can stand on it and it just pops back into shape

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AUS718 said...

That's an interesting rear strap design keef
Pepe47 any more weed fin designs in the pipe line.

I can assure you I won't be using any more kevlar , that stuff will try the patience of a saint!!
I've ordered a maui ultra 44 slalom weed which will become a 41 with the same rake of 42 degrees.

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keef said...

pepe47 said...

With my powerbox fins I've found through trial and error that the brass barrel nut will strip if I hit a rock or similar obstacle large enough to rip the fin from the board. This could open up an argument for and against power/tuttle boxes, but ensuring that the fin is secured to the board to the point where the board is going to be damaged just doesn't cut it.
For my money the fin almost has to be "sacrificial" if you're in conditions where fin damage may occur. Each time I find some limestone I just hope the fin has taken the full force of the strike. I certainly won't re-enforce the anchor point of the fin with any washer larger than the stock one.
Also when I rebox any fin I won't use too much re-enforcement around the barrel nut for that purpose.

ill have to agree pepe47, i just reboxed a tabou power box , the post were you screw the fin in snapped and the box just fell out of the board, the box wasnt resined in , it was held in with expanding urathane foam

Uh oh, hope my rocket boxes are secured better than that

pepe47 I saw a manta that matt pritchard had run in to a rock shelf at full speed, only put a small mark in the back of the box and pulled the front screw in to the deck and bent bothscrews at 45. So I think the boxes are in pretty good.

You might be able to try nylon bolts if you're worried about it, we used to use them to hold model aircraft wings on, they break in a hard crash.

Biggest problem I've found is that the fin rakes back and punches through the back of the board behind the finbox when you hit something.

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nebbian said...

You might be able to try nylon bolts if you're worried about it, we used to use them to hold model aircraft wings on, they break in a hard crash.

Biggest problem I've found is that the fin rakes back and punches through the back of the board behind the finbox when you hit something.

I seem to recall someone doing that at shoemakers

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nebbian said...

You might be able to try nylon bolts if you're worried about it, we used to use them to hold model aircraft wings on, they break in a hard crash.

Biggest problem I've found is that the fin rakes back and punches through the back of the board behind the finbox when you hit something.

i think thats the answer nylon bolts, ive beffed up my next box with 10ml divinicell and the sleeve's
so if the fin comes through the back of the box water won't get into the core