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Balsa Twin Fin

Posted: Mon Aug 20, 2012 8:16 pm
by Uncle Grumpy
This project has taken much longer then it should have but after months of trials, tribulations, deaths and disasters, it finally lacks just a coat of paste wax for the hull and surf wax for the deck.
Balsa, Redwood Stringers, Plywood Fins, 6 oz.top and bottom, glassed with epoxy resin.
I'll post the process in a series.

Balsa left over from another project
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Much easier to glue up in sections than to try and do it all at once.
Notice the stringer glued up using just tape. Epoxy rocks.
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A little shorter than I prefer but I'm working with what I have.
The blank is less than 45"
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Re: Balsa Twin Fin

Posted: Mon Aug 20, 2012 8:34 pm
by Uncle Grumpy
Plan shape.
This board will be a little Greenough, a little Goddard and a bit 'o Simmons.
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When I'm working on surfboards I shove my work bench over, cover the skylight and lower my shoplights for the groovy shaping room effect.
You can see my Bosch planer hooked up to the shopvac on the bench at left.
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After a bit of shaping...
When I glued up the blank there were a couple small checks on the end of two of the boards that ended up being big voids that I had to deal with....
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Re: Balsa Twin Fin

Posted: Mon Aug 20, 2012 8:52 pm
by Uncle Grumpy
Thick in the back, thin in the front.
Concave Deck+Parallel Rails+Wide Tail = Fast & Fun
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The dark line on this side of the right stringer is part of the void I had to fill....
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I didn't get any pictures during the glassing, my camera went haywire and it's so messy anyway..
This shot's after the intial lamination.
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Re: Balsa Twin Fin

Posted: Mon Aug 20, 2012 8:58 pm
by Uncle Grumpy
I never got to take pics of the fin shaping, due to the camera gone wonky but here's a shot of the initial fin glass job.
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My SWIMPAL has run off with my new camera so I'll finish this tomorrow with shots of the completed board.........

Re: Balsa Twin Fin

Posted: Tue Aug 21, 2012 10:16 am
by GeoffreyLevens
Looking good! Very interested in getting your ride report since you usually ride alaia type boards yes? so you have a particular perspective and a feeling/response you are used to that is different from most. Maybe kind of funny to say "most" in terms of paipo riders since the entire world crew isn't really that big of a sample (omitting standard bodyboards as they are just that, standard and dime a dozen)

Re: Balsa Twin Fin

Posted: Tue Aug 21, 2012 10:43 am
by Uncle Grumpy
Yeah the alaia' s are my go to boards because they work so well in our typical small waves.
I'll be using this board for the days when it gets too big or grindy for me to ride an alaia, so you might have to wait a while for a ride report.
Finished pics to follow.

Re: Balsa Twin Fin

Posted: Tue Aug 21, 2012 10:50 am
by GeoffreyLevens
Just for fun sometime though you might get inspired (ya never know) to take it out on a smaller, "more typical" day, just to see.... ;)

Re: Balsa Twin Fin

Posted: Tue Aug 21, 2012 11:09 am
by Uncle Grumpy
Finished.
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43.25" X 18.25" X 1.25"
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Re: Balsa Twin Fin

Posted: Tue Aug 21, 2012 11:16 am
by Uncle Grumpy
Details.
Brownie Points to all those who can identify the logo.
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Glassed on leash loop.
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Ready to ride.
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Re: Balsa Twin Fin

Posted: Thu Aug 23, 2012 5:10 pm
by Uncle Grumpy
A couple more pictures.
Shot under the lights of SHF
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Re: Balsa Twin Fin

Posted: Thu Aug 23, 2012 9:28 pm
by scrapster
Sweet. The contours on the deck are beautifully done. As for the logo--it's killing me. I've definitely seen it before. Not the Seabees, but I'm thinking Navy? I remember a cigar in its mouth.

Re: Balsa Twin Fin

Posted: Thu Aug 23, 2012 10:45 pm
by Uncle Grumpy
Here's a big hint.
The symbol is near and dear to a couple wrinkled old guys, one named Abe and another named Monty........... :mrgreen:

Re: Balsa Twin Fin

Posted: Fri Aug 24, 2012 9:12 pm
by dr robert
wondering why the dished out deck..?
performance characteristics..aesthetics..?
what's the template inspiration?

Re: Balsa Twin Fin

Posted: Fri Aug 24, 2012 10:33 pm
by Uncle Grumpy
dr robert wrote:wondering why the dished out deck..?
performance characteristics..aesthetics..?
Lowered center of gravity, comfort, less bouyancy for easier duck diving.....
dr robert wrote:what's the template inspiration?
Did you miss the second post in the thread?

a little Greenough, a little Goddard and a bit 'o Simmons

Re: Balsa Twin Fin

Posted: Sat Aug 25, 2012 12:43 am
by ClanB
Nice Nice. :o Im impressed.

Re: Balsa Twin Fin

Posted: Sat Aug 25, 2012 6:55 pm
by Uncle Grumpy
Thanks.

Re: Balsa Twin Fin

Posted: Sat Aug 25, 2012 10:21 pm
by dr robert
hey U.Grumpy,
nice work!
I did see your description on the template..but thought there might be a bit more to it than just generally referencing inspiration from 3 different shaper/designers.
Surf on.

Re: Balsa Twin Fin

Posted: Sun Aug 26, 2012 8:07 pm
by Uncle Grumpy
Again, thanks,
FWIW, this is the first surfboard I've ever made with fins and glass.
I was looking to get the most out of the materials I had on hand.
If you've seen the Goddard Design Sheets http://mypaipoboards.org/interviews/Lar ... humb.shtml
It seems there is just about every iteration of modern style prone boards imaginable.
I took what I thought would work for me and went with it.
Surfboards are much like boats, if it looks good it will probably work; but they are all a compromise. :ugeek:

Re: Balsa Twin Fin

Posted: Sun Aug 26, 2012 9:01 pm
by dr robert
U. Grumpy,
excellent!
how great is it to have the Goddard stuff..many thanks to Bob and Rod for getting this all information together.
everybody benefits.
I'm sure your board is a screamer!

Re: Balsa Twin Fin

Posted: Sun Aug 26, 2012 10:06 pm
by Uncle Grumpy
I finished the board at the end of the last swell and have been patiently waiting for some proper waves for the debut.
1-2' onshore junk is not appropriate. I want the first session to be memorable
My good friends at Magic Seaweed are telling me this next week ought to be productive. :mrgreen: