I second that, it looks awesome indeed!
Is it all done by hand using a file?
How long did it take you?
Did you use anything to help you with the foil profile? (e.g. finfoil height contours)
Some fins I made for an asymmetrical last winter. G-10 base with mesquite on the “quad” side and live oak on the keel.
You can buy a handle at ACE or the Depot. Post a pic of the file. If it is the standard pointy end you can get a handle for just a few $$. Made specific for a file they hold better than just dowel or broomstick.
Full story here: https://www.swaylocks.com/forums/shallow-water-fin-design-build-ride-report
The layup is a multiplex core covered with 1 layer 200g/m2 carbon fibre at 45deg and 1 layer 160g/m2 glass at 0deg mainly meant as abrasive protection. The leading edge is also reinforced with glass rope.
6.15" MR template with tweaked trailing edge, tabs are cut for Gearbox fin system. 1/8" FR4 (Black G10) panel + 3 layers of 1/8" Aircraft ply = 18 plys total plus a couple layers of fiberglass over the G10
Fin is 1/2" thick. I had to bevel the bottom of the fat part of the foil to fit the finbox cant.
Great stuff!
Did you use finfoil to calculate the slice contours?
If so, can I share these pictures on my twitter feed?
Well done!
I sure did use Finfoil. I love your program even though I do everything by hand. I used the first one below to template the two top layers. The 2nd one shows what I was aiming for with the full foil. Obviously the G10 layer is foiled, too so it doesn’t show in the pics - but it’s there.
I’m still a novice at foiling fins so I didn’t quite match the foil the CAD laid out but I’m working on it. I may get there someday.
These are huge fins (26"), but they go on a 6-10 x 24 x 3.5 board that I built for a 260+# surfer, so he has the stature to push these around.
Those, sir, are simply bitchin. Beautiful work.
Has anyone successfully made their own fins to fit the FCSII boxes? Not talking twin tabs as I know they work with screws. I’m talking made so they pop in and out as the box is designed.
Sorry that I didn’t see the question Hans. I did the foiling with a vixen file and a 7" disk sander. Everything is by eye, I draw a line to get a center then go at it. The G10 has such a nice pattern that it lets you see the foil. I foiled it 3 times before I was happy. The tip was a bit too thick at first, so I took it down a little, then did that again. I’m pretty happy with the end result. The G10 was actually 3/4" thick. If I were to do this more often, I’d make a jig to sand the thickness from bottom to tip first, and use a benchtop sander, then foil it after the thickness was set.
I was considering making a FCS2 fin for my cousin, but have no FCS2 fins or boards with fcs2 plugs to fondle and use for test fitting
However I think I will make a fcs1 fin with much wider tabs to spread the load, which can still be used in an fcs2 receptacle employing the grub screws, and also fit into Probox, which I use.
Those blades belong to a very handy tool that car body repair shops use. It can be bent to convex or concave shapes.
10TH or so home hade fins. !st fins I used balsa but didn’t glass them good enough and Snap off they came.
Since then I have made epoxy panels out of cloth, (I think this type of composite is refered to as Micarta). Works prety good but after surfing them for 6 months they started to permanantly deform at the tips. I didnt add any additional glass to them after they were shaped therefore the micarta composite could not withstand the repeated stress so the tips of the fins bent inward. I made about 5 tp 8 sets of fins out of that material, then I started using 5 layered baltic birch.
This is my 2nd par using this plywood and I have to say that I think I am finally begining to be able to foil BOTH fins the same. I see that there is some minor differences between the outermost ply layer in the center, but negligable.
I weighed both fins and the difference in 0.4grams, but well see after I glass them and mold the future base.
What do you think?
Nothing fancy. First glass on’s I’ve done in years. The process brought back a few things I had forgotten. Like why you always put glass on the flat side of wooden side bites just a tad bigger than your wooden fin.
On u-tube " robiegle" I explain how I make them.
Cheers
I also do my fins like that. Wood core and fibers outside. Just be aware that there is a point load where the fin enters the board. Make sure that some strong fibers pass through this section. I would recommend to make the wood core myself. So you can drag a layer of carbon, basalt or glass through this area (The red highlighted layer in my upload). Then you can apply a layer of veneer from the outside (marked in green) and then form the profile and then laminate everything with glass fibers.
See “robiegle” on u-tube
Robiegle, I actually add 5 layers of 4oz fiberglass to the fins, 2 on the inside and 3 on the outside face. I extend it down into the tab, then I mould the base with cant into that wood tab & glass. It works pretty good so far as I havent had any break.
How do those fins in the last picture work? They look like they would be a good trailer fin with a twin setup.
I made one similar to that one, specifically for use as a trailer fin with twin fins. I think that the high aspect ratio of that type of fin as a trailer works great. It gives the board just enough hold so that you can realy crank out a bottom turn, or whatever without the tail sliding out. Those nubster fins that are sold for that purpose are, in my opinion garbage. I used one once and it felt like a brick was tied to my board.
The fins I call TANTO, like the japanese short sword. They fit only in boards with three plugs (I always put one in between the two regular ones). Like this I can make fins with a very narrow base and I can shift them by one plug. I made them for my quad board and I must say, they don’t work really good. The FCS K2.1 quad fins, or the Split Keels I prefer…
But I like to try different things.