I love those layups
Thanks John, It’s my 3rd board. I restore rusty old vehicles for a living so getting some shine is easy…just need more shaping time (but it does ride suprisingly well).
THIRD board, Seriously?!
That’s a quotable description if ever I’ve seen one.
High aspect ratio. Western red cedar with 3 layers of woven roving core.
Being Made for Probox
4 inch base, 15/32 max thickness.
So what is that Ply? 10 Ply Marine?
Yes, very nice
Someday I’m going to make some fins with the 3/4" or 1" base and more complete foil. That’s where the use of ply + fiberglass spine will pay off.
Made these for the last fish I shaped. Pretty much the standard Geppy outline I reckon, but 80/20. They whislte when I’m going really fast though. Maybe too thick, maybe an issue concerning cant/toe. who knows.
About to do some slightly different ones for another fish.
I like the look of the rovings.
Did you weave them yourself (from plain non-woven rovings) or did you use some sort of FG rope?
How did you layer them?
Woven roving is like E cloth, but instead of each strand in the weave being 1/16" wide, they are 1/4 inch wide. Its like cloth woven with that roll of roving/fin rope you just bought.
I usually buy it just to pull individual strands from it, Only once before had i wetted it out as a woven cloth and not for anything remotely surfboard related.
I cut 3 rectangles of this woven roving bigger than the cedar I had cut out, and wet them individually, cursed that they did not want to go completely clear despite much efforts, then sandwiched them inbetween the cedar. Waxed Plate glass on both sides with several pounds of weight atop to make the fin panel. I can make 2 more full size rail fins and perhaps one smaller trailer.
But honestly have so little desire to repeat the process anytime soon.
I used the woven roving as I did not have enough other cloth. I was guessing at 3 layers, but 2 layers might have been enough. The fin is so stiff, but I got the tip pretty thin, and there is ‘some’ flex there.
Whistling often occurs when the trailing edge of the fin(s) hasn’t been sharpened enough. Check that first.
Are you insane? Too thick? Probably not thick enough. Make your next fins 3/4th inches thick, with a symmetrical foil. Blunt rounded leading edge, and sharp trailing edge, with highest camber at 40% of the base chord. NO TOE, NO CANT. I’ve been making what are described as ‘‘thick fins’’, since 1960. I’ve never had a thick fin hum, or whistle. You ask, who knows? Me, I know.
Get rid of any resin beads along the trailing edge…and like Bill said, thick is good!
The fin wound up being 11.86mm thick, 102.11 base width. 5&7/8" ~128mm depth.
Contour gauge in photo was pressed onto fin’s foil ~1 cm from base.
Flat inner side has carbon strips through the cedar touching the 3 layers of woven roving core. Grub screws will also push down on carbon fiber added to U shaped grooves which are bridging those carbon strips.
I used extremely small drill bits in my dremel through cedar, and the roving, to increase surface area of the next bonding layer of epoxy along base and Halo.
FCS1 production fins wobble in the proboxes, requiring grub screws to tighten them within.
This fin is a friction fit, the grub screws merely retain the fin in the probox six degree insert.
Footbone connected to finbone’s very tip. Methinks any squish between foot and fin base is not beneficial.
The contour gauge, is not being very nice to previous fins I made, and not really as kind as I would like with this fin.
Shadow shaping of fin foils leaves a lot of room for error.
My carbon fiber FCS1 TCredline center fin weighs 0.1oz less, a FCS1 abs injected Rusty template rail fin weighs 0.3oz more.
The hours of labor required to finish this fin are firmly into the highly ridiculous range.
I’ve little, to no desire to make another.
Should be enough swell to ride it fairly soon.
The Times i was able to engage the toe side rail with the fin above, I liked it, so today I attempted to foil a twin of the twin, for my heel side rail.
My first try at making my own fins. (the pile of cutoff cloth from my board laminations got to big)
Kind of Akila Aipa style twin fins.
Foiling was quite good fun. Surely not the last fins I built.
I’ve had a 1/2" (maybe slightly thicker) thick piece of G10 waiting to be turned into fins for a while, so I started working on 2 yesterday. One will be a 9" Greenough 4A, and the other is a 7" Brewer. Hardest part is cutting the outline then getting the bottom to the fit a 3/8" thick box. I finished the Brewer today, but in the process of working on it, my new Vixen file decided to leave an imprint on the fingers. Yeah, I know, I should have worn a glove. Man the file is so much sharper than the old one, but it was made to be screwed onto a handle, like an autobody file. Next job is make a handle for the file.
That fin looks awesome! Nice work Harry.