thanks Woody , and …you’re welcome mate .
And thanks Bert Burger , Paul Jensen and plusoneshaper for your inspiration, too !
Now , “Woody” , you can live up to your name… and make heaps of different wooden core fins with moulded bases for your boards .
…what fin system[s] do you have on your board[s] ?
cheers mate !
ben
p.s. …
I’m no expert , by any means , but feel free to “p.m.” when you start making the fins, and doing the bases …I hope I can be of help to you .
Amen to that, I 1st became interested in making fins while on surfari, talking shop in tunnel vission, they stock the rainbow works fins that Locbox posted on Bert’s fin trent, and I was so impressed by their quaility, they really are beatiful objects to aspire to.
I owe so much, to so many different people, espeically here on sways, these guys are the salt of the earth (or the sea), much respect.
I could easily spend the rest of my life giving praise to every one thats helped me, but instead I’m going to make the best boards and fins I can i can in their honour, and each board I make is as much a part of them is it is of me, so if you ever meet one of my creations on some distant shore, I hope it will feel like a familiar friend.
And Ben thanks for not letting me take things for granted, keeping me motivated with the odd gental push in the right direction, without the sways crew, I would never have come as far as I have, still a long road to tred but every step along the way is a magical experince, so now it is time to get to get off the computer go that hardware store, and get busy with it.
Catch ya latta
post photos of your progress please Woodster !
cheers !
ben
I use this tool to put bases on fin blanks. It gets lined with parchment paper and the ends plugged off to stop overflow. Each side of the fin gets 4 or 5 layers of 10 oz tape and is then filled with resin.
This is the fin blank before base. It’s 16 layers of six oz cloth.
Remove from tool when cured and sand to fit box, install pin and cut other end for screw and drill hole.
The fin after sanding and fitting to the box.
Next picture is of the fin ready to be covered with foam. I use a 4 lb two part urathane foam. It’s real hard when cured, but shapes easily with a wood rasp and 60 grit paper.
Foam is then poured on one side and allowed to cure.
After foam cures on one side , repeat on other side. I use a fine pull saw to cut the sides to the thickness I need. Next step is to use rasp to shape foil in the foam.
here’s the base on one of the twin keels I made for Luke . [They have now arrived on the other side of Australia… ]
Ready to go!!!
Finished sanding her last night and will get the keels in the water tomorrow with luck. Onya Ben and Hicksy, thanks heaps
After shaping it gets a single layer of 6 oz cloth, a sanding coat and a clear spray finish. I have painted some of the foam with latex paint before laminating and it seems to work fine. I found that by using the foam as both a surface to foil and added stiffness, I only need 16 layers of six ounce cloth to lay up the fin blank. If more stiffness is needed, another layer of cloth could be added.
Hola!
2-part polyurethane foam??? I didn’t know about that. It’s just what I need for fixing my big delam problem!! I tried some months ago to fill the 10-20mm deep valley on the deck of my old longboard using polyurethane foam in a can (that one used for fill gaps between windows and walls) but it simply didn’t stick to the foam.
Please, anybody know a 2-part urethane foam brand in Europe???
I get mine from US Composites. I’m located in NE Florida, USA, so I don’t know if this company will work for you. I use the 4lb density, which is plenty strong but still shapable with wood working tools. The other advantages of using foam is that it’s easier to shape then plywood, not as itchy as foiling fiberglass and their weight is offset some in the water by the flotation of the foam.
If after completing and using a fin for a while, I can remove the glass skin and the foam to end up with the fiberglass blank and build another fin.
I suppose they can crack and take on water, but I haven’t had that happen yet.
Dan
thanks a lot for that series of photos Dan …brilliant idea !
I think that MAY be how they made some old glass on twinfins I had on an old rubbish dump find board once …
ben
Hi retired44,
great series, I especially like the clmp you use to hold the fin in position, can you also use it yo set cant?,
I was thinking ot something along those lines for the jig I’m working on now, also I want to incorparate a sliding stop to alter the length of the tab.
how a bout a close up?
In the picture, there is a small level and plumb bob that I use to make sure the fin is perpendicular to the base of the tool. I use the level to true the table and the plumb bob to be sure that the tip of the fin is at a right angle to the table. It could also be used to set up cant by off-setting the top to place the fin in the base at whatever angle you choose, although I only have made fins for longboards that require no cant. The trough for the fin base is just the right size groove milled into a 2" by 2" piece of oak and sealed with poly resin. I use wooden wedges at each end to set the length of the base and cut them off later for reuse.
I find the parchment paper works well as it peels off easily from the resin and I don’t have to pretreat the base mold. Just be sure there are no small tears in the parchment or leaking can occur and cause you to cut another piece of oak (the voice of experience).
Dan
Ah yes, a plum bob and spirit level, thats great, now why did I not think of that?
The simplest and most effectife sollutions are always the ones that it takes longest to arrive at, or get pointed out by some one else and then kick your self for mot realising it sooner. I seem to have a habit of taking the long way round.
Cheers Dan
Gents
I am looking for a Polyurthane casting resin.
Does anyone know a brand/product that gives a fast setting time, low shrinkage and is pretty hard when cured?
Would be very interested to hear what you guys have used for Fin boxes and your general thoughts on the stuff you used.
Don’t know that it would work for FU or Bahne boxes as the bases tend to vary greatly, but for FCS, Future, LokBox, ProBox etc., I got two words for you; Silicone Molds.
Friend suggested it…build a box a wee bit deeper and longer than your tab, but shorter than your master fin (stock pre-fab fin you bought with your boxes). Cut yourself a jig with two long slots (with spacers underneath to lift it off the box); let’s say 1/2" wide on the middle beam, with two half inch slots. Fill the box up close to the brim with silicone. I used Dow-Corning HS2 RTV, though you may be able to get away with lower grade “outta the tube” type sealing silicone. Drop the masters in so that the bottom of the fin is flush with the surface of the silicone with the leading and trailing tips hanging off the edge of the box, place the spacer and jig and line the fins up so that they’re vertical; flush with the middle bar. Put a vertical spacer of 1/2" between the fins vertically as well to insure they stay straight and even. Now let the silicone set and pull the masters out once that’s done (24h in my case).
Then, when you wanna cast your bases, take your fin with a dummy tab already attached and cut slightly smaller than the final tab size. Fill the mold with resin of your choosing (and you SHOULD be choosing epoxy here) with some milled fiber mixed in. Make sure you use your stir stick to fully cover the sides of the mold…drop your home made fins in and set the jig up again, with the same spacers and the like; let the resin set. The silicone releases really nicely from the epoxy, once it’s cured and you get a tab that will require an absolute minimum of sanding to fit. Did this with some ProBox fins last night; will post “how to” photos when I get home. Hands down, the easiest way I can think of to get reproducible results when molding on a tab…
Cheers!
GNW
I make my molds out of spare teflon, three pieces machining, took 20 minutes to make, works like a charm for adding cant to fin bases. No need for mold release from teflon if you are careful to machine a smooth surface on the sides of the mold.
ok here’s my rendition…
spare wood plank buns e-taped…
meat is narrow wood lattice same width as stock fin base…the three are clamped down in a sandwich as shown
the fins are my homemade molded, foam/balsa core, light, super stiff carbon fatty floaties…foil width is 10% of chord length…45 grams b4 base molding
hopefully just in time for hurricane season…
hi Meecrafty !
…do you have a shot looking down the box , or an "exploded view " of the parts of the box , please ?
thanks !
ben
hi ben, not really much to it but here’s a down-the-line pic…i just used what i had lying around the garage…
crude but effective…my specialty 
