How to fix a US Box Fin

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Randy
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Joined: 05/05/2002 - 10:38
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How to fix a US Box Fin

I found this trying to figure out how to fix a broken tab on my US box fin. Hardest part (which I didn't do great) was drilling the new hole.

https://www.youtube.com/watch?v=zx0jFvST5vE

What happens in a black hole stays in a black hole.

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Randy
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Re: How to fix a US Box Fin

Pix of what I did. I didn't need to cut any of the fin away, and probably cut more of the base away than I needed to.

What happens in a black hole stays in a black hole.

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webguy
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Re: How to fix a US Box Fin

I think you did a better job. Here's an interesting old thread on Swaylocks: https://www.swaylocks.com/forum/65465/longboard-fin-repair

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Re: How to fix a US Box Fin

That's interesting. I had already used superglue to bond the split, but it gave away today when I was trying to drill a hole in the base. The maddening thing about these type of fins is the peg is not always the same height from the bottom of the base, so they don't always fit into the slot in the fin box. To fix that problem I removed the peg and drilled a new hole for it.....After doing that I noticed the glued tab failed (and it was worse than I realized anyway).

I think another way of doing this repair that might be easier is cut away the tab, drill a small hole into the base and screw in a small eyebolt in place of the tab......I wait till my new repair fails to try that.

Same idea as this:

https://www.cygnus-sails.com/item-US_Fin_Repair_Kit.html

Too bad the US fin repair kite seems to be only sold in the UK. (Even worse - I think I had one but had no idea what it was and threw away.)

Anyway, the moral of this story is don't hit anything with your fin (which should be easy after getting used to foil type depths) and never rest the board on the fin....

What happens in a black hole stays in a black hole.

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Re: How to fix a US Box Fin

The Swaylock thread had another helpful tip - clamp the tab between vice grips or a clamp to inhibit splitting when you drill. I don't think splitting is the end of the world unless you are removing the fin often. The fin box is going to be constraining the fin tab and as long as it's sound in the z axis so the fin doesn't pivot back, you should be good.

Again, nice job.

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Re: How to fix a US Box Fin

Thanks.

What happens in a black hole stays in a black hole.

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