How To Install A Longboard Center Fin Box

All comments, suggestions, insults and jokes welcome. Proper spelling and grammar are not required.

These instructions will work for the Fins Unlimited box and the High Surf box.

Figure out where you want to put the box and measure the board thickness. You will need about 1 inch for the box plus a little extra so you don't route a hole through to the deck. If you have a really thin tail you can still install the box. We can talk about that later.

 

 

 



My board measured 1 1/8" thich. Perfect

If you are good with tools you can cut out the hole free hand. I made a jig out of plywood.

 

There's lots of options when it comes to routers. Mine is about 20 years old. The bit I'm using came from my old ProBox install kit. I don't know much about routers and bits. My bit has a bearing that rides along the jig. If you have never used a router before get some help. The router is a Knarly tool. You might want to do some practice runs before you ruin a good surfboard. Several small cuts are better than one deep cut.

 

 

After you cut out the hole make sure the box fits.

 

 


Now is a good time to drill the hole for your leash rope. With the box in the hole measure from the tail. Your hole needs to be close to the back of the box but not all the way back. Now flip the board over and mark the deck. I've always used a small drill bit first and then a bigger bit to get the hole size I want. I read on Swaylock's about a special bit that drills the pilot hole and the main hole at the same time. I bought one and it works great. I don't know what it's called, maybe one of the wood workers can help us out. After you drill the leash rope hole put some tape over it.

 

 


This is my mock up fin

 

iz dat a penc bord.  sree Im culr blnd.   mic

I like to line the hole with 6 oz cloth. I do mostly EPS / Epoxy now. I've had some major melt downs. My fin box will get done with 2 pours. It's a good idea to level your board at this point.

 

 


[quote="$1"]

iz dat a penc bord.  sree Im culr blnd.   mic

[/quote]

 

Fun Fun Fun!

Carefully place the dry cloth into the hole. Move it around, make it nice and smooth. Now pull up the cloth where the leash rope hole is. Pour resin into the leash rope hole. Put the cloth back down. Pour resin the lenght of the hole. Just a little bit. Now use your finger to move around the resin and get the cloth wet on the sides of the hole. Pour in a little more resin.

Set the box.

 

 


After everything has cured drill your small leash rope hole and grind off the top of the box.

 

 

You go to great detail on how to install a box, but your resin work on the rails is completely unacceptable.  Apply similar care to your resin work.

Wow, ray goes to the trouble to post a helpful thread, and gets flamed. I don't remember reading anything about rails in this thread. We're not all experts as you so obviously are.

A bit of attention with a squeegee, brush or finger would have eliminated the need to grind all the drips and made a better and easier to sand product.  I thought my critique tactful, for the people I have worked with would cuss you out the first time, punch you out the second, and a third time would be somewhere else.   

Thanks Stingray, I'm looking to convert a board that's not really working as a round tail step-up quad so keen to put a fin-box in and see how it goes as a 2+1. These steps are just what I need to get me started. I have some old snapped boards that I'll have a few practice runs on first with the router.

      Howzit ghettorat, The more I look at the picture and there is a grinder in it I think it's sanded resin dust that hasn't been cleaned off yet, I am just speculating because stingray builds good boards from what I've seen over the years. I know it looks like dry unsaturated fiberglass but I think stingray should tell us. Aloha,Kokua

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You go to great detail on how to install a box, but your resin work on the rails is completely unacceptable.  Apply similar care to your resin work.

[/quote]

 

I have thick skin. Say what you want. I don't really give a shit....

Are you a Pro? Do you help people build boards? Do you post photos of your awesome work?  Do you post photos of projects that are 1/2 done. I'm working on a prototype project with two other garage builders. This is not a thread about cut laps or awesome color work.

 I am a garage builder. I want to help other garage builders build better boards. This thread is about center fin boxes.

Care to help us? How do you install a longboard center fin box?

 

Ray

"All comments, suggestions, insults and jokes welcome. Proper spelling and grammar are not required"

A real critique and you so small minded you take it as criticism; funny you even invite it in your post, but can not take it.   If you go back and read my comments on other aspects of board building you will see I know what I am talking about, and that means I know more than you.  Once again, I hope I am not casting pearls before swine. 

Nevertheless, I will tell you how I put in a fin box.  I use a porter-cable 690 1 1/2 router, which is a great tool although sometimes  I have to chip away in stages at the stringers.  Also, I use a o’fish’l center fin jig that I got from Mell Ross who founded o’fish’l and argueably  laminated more boards than anyone in the world, and the most coveted old boards were probably laminated by him.  O, yeah, he taught me the basics on laminating.  Another pretty darn good laminator who I picked some techniques up from are Bobby Allen, who did the Noll’s and Greg Marx, whom he showed the basics.  I could go on and on ,and list a few others, like Jeff Wells at lost and and good youngster Gregg Webster.  Now I tape the jig to the board with 2’’ masking tape and try not to clamp the jig to the box like you have shown because it tends to leave dents in the deck.  The o’fish’l fin jig you can purchase from Mark Stavron in San Clemente who now owns o’fish’l. 

Now that I have dropped a couple heavy names, here is a hint that will prove most useful:  route out  the stringer first before finishing the fibreglass perimeter.  Furthermore don’t try to move the router too quickly or you will start to burn the stringer and surrounding materials, as well as, send shrapnel into places that you will not like.  

O get a little thicker skin or I refer to you in the future as “thinskinray”.