? FOILING WOODEN FINS ?

fins · January 9, 2013, 9:46am

Hi crew !

there are some really nicely foiled wooden fins on the

"show us your home made fins"

thread ....

so , I wanted to ask ....

What do you guys use , for the foiling ?

I ask , because , yesterday , after foiling 16 FIBREGLASS fins , I needed a break from glass dust .

I have a few pretty nice wood fins that some swaylockians have very kindly sent me over the years .

So , I thought ,

"it's ABOUT TIME I had a go at foiling some !"

here is one that "thefishexp" [Cameron] sent me , AGES ago , which he foiled ...

the other one he left unfoiled , providing me with the challenge to match his foil [mighta been why I have hesitated so long , methinks ??!!]

anyway , I ripped into it [literally , unfortunately !] with the sander ...

here is the ROUGH preliminary foil , yet to be smoothed out with a sanding block , to 'attempt' to match HIS foiled one !

...is THAT how YOU guys do it , generally ?

I felt a bit heavy-handed , as a bit of pressure is applied to GLASS panels , ? wood not so much , perhaps ?

do you get 'burn marks ' on your wood blanks , sometimes ??

( I DID ....THIS is what happened to one 'woodmaven' kindly sent me ...hopefully I can 'rescue' it ?

....A nice pair of twinnys , that I was attempting to thin down, a bit ...oops !! )

here's "the pair "... Rolly generously thinned the tab for me , so I can build it up with lots of cloth , to make it STRONG ! [ I may even use a few layers of carbon fibre on the tab area too, I think ! ]

greenlight · January 9, 2013, 2:17pm

Maybe try a softer pad for wood fins if you have a heavy hand. Also, a lighter weight sander helps a lot. I used to use my Milwaukee to foil fins and switched to our Greenlight sanders which are about 1/3rd the weight. Much easier to control and the old forearms don’t burn as much!

Also, fresh sandpaper will help to not scorch the wood. As the paper clogs up it’s not cutting and just creating friction burns.

Love your fins! Keep posting 'em

~Brian

fins · January 9, 2013, 8:33pm

..... thanks very much for that feedback , Brian , that's MOST helpful !!

Yes , I use sanding discs , on a grinder , to foil all my fins ...would it also be that the revs are too high on that , compared to the sanders you use , I wonder ?? works fine for fibreglass , where I need to be able to take away LOTS of material QUICKLY ...with wood , probably not really want I need / want to do so much , eh ?

Also , what grit of sandpaper do you use , on your wooden fins , please , Brian ? [mine are 40 grit ...they work fine for fibreglass ... but , would that be a bit too coarse for foiling wood ones , do you reckon ?]

I HAVE practiced on bits of scrap wood now , and am lightening my 'touch' for the wood . :)

glad you enjoy my fins ! ..... I certainly enjoy making them ! [ and test riding them , too , of course ! .... "my fin tinkerings" , INDEED ! :) :) ;)]

yes , 'all going well' , I HOPE to continue to post photos of more !

I certainly have HEAPS more fins blanks here , which it looks as though I WILL have to foil , as I really had very little response to my "anyone need fin blanks ? " thread . It seems people prefer buying cheaper plastic fins , perhaps use glassons only , or else don't want to have to do the "work" involved , in foiling fins . Which is a bit ironic , really , as it takes much longer to lay up fin panels , and costs more , than it does to FOIL them ... (ESPECIALLY when I have already done [maybe] 90 % of the work ..... in laying up the panel , and have drawn up , and cut out , the templates for people ?! oh , well .... "such is life" , I suppose .....)

Anyway ... " NEXT" ....

.....I will be able to put your finbox screw attachment insert to good use , when I complete THIS fin , next ....

I am thinking to just lightly thin the base , as is , so I can glass it to fit firmly in a fin box , then saw out and resin [waterproof] the 'groove ' , for your screw attachment to go into. [Always put it on the FRONT of my homemade fins , so I can move them as far back in the finbox , as possible !]

Q:

Is there another way to attach a strong base to this I wonder , as I was kinda hoping to be able to use the whole fin's depth , and placing it in a box as it is , I will be losing roughly a 1/2" depth from the fin ?

This nicely made fin was sent to me , ages ago, by 'Gill' here at 'Swaylock's' [ that's Craig Gillespie, on facebook] , who is a woodwork teacher on the east coast of oz , and makes nice surfboards , too !]

okay , Brian ...

..... again , MANY thanks , and I hope that you are getting some nice waves , mate !

cheers , from oz !

ben

gdaddy · January 9, 2013, 8:44pm

I’m a novice at foiling fins so I really like using plywood so I can see what I’m doing. I aspire to get better foils with no flat spots. I’ve got more time than common sense so I used a file and a palm RO sander with 60 grit. It took a while. I’ll move up to using the bigger sander when I get more confident at it.

fins · January 10, 2013, 9:01am

....those ones you posted were actually what prompted my original opening comment , they looked pro to MY amateur eye , BEAUTIFUL work !

do you remember how long they took you , roughly ?

cheers

ben

tommorth · January 10, 2013, 9:11am

I find pulsing the trigger on the grinder helps otherwise it will eat lot of timber in a hurry.

fins · January 10, 2013, 2:32pm

cheers tom !

good advice here ,

please keep it coming , guys .... I'm all ears [and eyes , for reading !]

ben

Surfifty · January 10, 2013, 6:51pm

I use a Makita 5" hand held disc sander model GV5000. To prevent burning keep the tool moving to reduce heat build up and change discs when they clog.

gdaddy · January 10, 2013, 8:00pm

“do you remember how long they took you , roughly ?”

Like I said, you don’t want to know. I’ve got more time than common sense.

I went real slow because I don’t have a lot of experience with foiling fins and it’s easier to add foiling than it is to try to subtract foiling. Huie said before (in another thread) to go slow with wood so as to avoid mistakes, and I aspire to pay attention to good advice from my betters. I used a small file to bring the foil down at the base somewhat even with the rest of the foil. Since this is ply it’s a lot stronger than a single panel of wood would be so I felt comfortable treating it like fiberglass.

For the sides I built up the inside panels of the fins with enough fiberglass cloth to give me a decent halo. I did that before templating the fins. So my foil goes directly into the halo, same as if the entire panel was fiberglass. I just have to lay some glass over it to finish. I’m gonna try to get to that this weekend.

For the center I used 2 panels of 3/16 ply with a 1/16 panel of G-10 in the middle. (that panel was scrap so I got it for cheap), clamped under vacuum with epoxy. I used a layer of cloth between panels to get the adhesion. Since the panel came out at 1/2" before foiling I used my router to machine the base down so it would fit a finbox after glassing. I’ve always wanted to try a fat fin. I did that before foiling while the panel was still flat. My plan is to glass a 1/16th facing of G10 to each side of the base, so the wood won’t be exposed anywhere. Fingers crossed.

fins · January 11, 2013, 3:57am

great stuff gdaddy , excellent info and help !

if it took you a long time , that's GREAT !

In my limited experience , all my 'screw ups' have been as a result of rushing things .

I mean , really , "WHAT is the hurry , mr.chipper ? ...the ocean , all going well, is still going to be there !"

as you say , once the wood and the the glass [in my case] is foiled off , it ain't easy "putting it back on " haha

yep , huie's fins look awesome , I might be picking his brains somewhat .

I want to go very carefully and slowly , when I get to foiling the fibreglass fins I laid up , using the coremat material he kindly sent me .

patience grasshopper , patience ...it has been the same with my ...er..."board shaping" [limited] experiences ...don't know why , but for some reason I hurry them ? again ...the ocean will always be there , waves will always come ! [even if "eventually " , during summer flat spells ] Better to have spent a few hours doing a good job of whatever , than to have paddled out on a board I was only maybe 60 % happy with . Because then , that board often doesn't end up getting ridden much , I found ....

I definately want to make more wooden fins , thanks for the inspiration , guys !

I have plywood lying around here ....

I really "should" make fins from it , before these prolific , pesky hot weather cockroaches decide to breakfast , lunch , and dinner [and midnight ] snack on it , and all I am left with is DUST !!

cheers

ben

fins · January 11, 2013, 4:33am

okay , my next wood fin related question ,

relates to THIS one ...

I was kindly donated this by a friend , before he moved east [to Queensland] .

As you can see , it is already foiled ...

and partially glassed ?

.... and , sanded ?!

so, my question is this ....

do you think it would be better to keep sanding that glassed side back , also getting rid of the partial 'glass halo ' around the edge , before adding more cloth ?

I'm thinking at LEAST two layers of six oz , each side of the fin . ( And , obviously , HEAPS more on the base , to build it back up to fin box thickness ! )

I like the fin's foil and appearance , and am keen to have a [fairly] flexy fin in my quiver , again ...

Finally , two last questions [sorry] ....

...DO flexy WOOD fins tend to crack near the base , or halway up the fin , I wonder ?

.... if so , how many layers of cloth do you guys reckon would help PREVENT this happening ?

I ask , because most all the old flexy FIBREGLASS single fins I have had over the years [eg: the 'Wilderness' hullible bottomed board I had , and others , too] had stress cracks across them ... often near the base , and middle areas , of the fin , more so than at the tip [?strangely , or not ?]

okay , cheers for any help on this , guys !

ben

Thefishexp · January 11, 2013, 12:11pm

Hi there Ben,

You’ve dragged me out of hiatus as I haven’t posted here in a while.

That fin didn’t take me too long to foil - about 15mins - here’s how I did it.

2 sanders. A 180mm sander polisher and a 150mm orbital sander
on the templated fin, draw the foil line in pencil (essentially the line to where the ply will be sanded)
clamp to the bench (clamp should be on the base on the area where the fin will not be foiled)
starting on the trailing edge, with the 180mm sander polisher (80 grit to go a little slower) make long sweeps from tip to base.
make sure you keep a steady hand and get the angle right to foil to your pencil line and down to a fine point in the trailing edge without going too fine of the point as this will effect the outline.
long sweeps and steady hands will get you that nice line. The ply is good to give you an indication of how clean and consistent your foil is
no need to go too fine at this point as you can clean up later with the orbital.
now do the same with the leading edge but remember the angle is different and you want to leave a bit more on the edge as the leading edge will be more rounded
once you’ve foiled the trailing and leading edges you need to foil down the tip. You could do this with the sander polisher but I switch to the orbital at this point to go a little slower and finer
with 80grit on the orbital foil down the tip - you need to knock a fair bit off to get it right.
then still with the orbital, clean up and blend the foil with the rest of the fin… You’re essentially now rounding and knocking off the edges, blending using the ply lines as a guide.
I also flip the fin over and knock off the leading edge on the unfoiled side of a side fin at this point. Something Robin Mair explained to me when I visited him once (which from memory was around the time if was making these fins)

Clean em up and you’re pretty much done. You only need to finish sand them to 120grit as you will need to glass them… I used the Bert Burger method that was on here somewhere.

Those fins bring back memories - the one I sent you was a practice foil that I did before doing a set of canard quads about 5 yeas back - ill try to dig up some photos of the finished product tomorrow for you.

greenlight · January 11, 2013, 12:43pm

Hi Ben

I use 60 grit @ about 3000 rpm. Wood cuts away quickly so not a lot of passes are needed. After rough foiling I use a Black & Decker ‘Mouse’ sander with 80 grit to fair out the curves. The less you touch wood fins the better.

Here’s a video I made a few years ago of me making bamboo keels for ProBox. Bamboo’s a bit more resistant to sanding than plywood so it takes more passes. (I’ll be getting another shipment of bamboo soon and get back into making bamboo fins and fin panels) I’m making some keels in the video so I’m using an 8" Powerpad but I normally use a 6" pad to get in tighter curves of a trailing edge.

Notice I release the trigger about 2/3rds the way up the fin on each pass to let the pad run out with lower rpms at the tips. You don’t want to grind too much off the tip!

As far as centerfin bases go. It’s best to design your in template with 3/4" (19mm) extra base depth and use a universal fin tab for the screw and plate.

~Brian

fins · January 12, 2013, 1:25pm

cam !!!

welcome back , mate !

great advice ...I will attempt to follow it on future wood fin projects !

brian

ditto !

thanks very much , guys !!

cheers

ben

western · January 12, 2013, 1:42pm

Hi Guys , I do similar with 60 grit paper in a fast cheap Bocsh grinder no guard , when it gets clogged if at all i pickit off with a hard nail , Failing that you can get a compound stick to clean your abrasives with .

After roughing out i like to clean up the wood with a 2nd cut file to even the shape out before sanding , something hard and flat like a file helps knock off bumps in resin easy !

Cheers

surfertravels · January 12, 2013, 2:48pm

What kind of wood do you reccomend that I make my fins out of? I have a couple of different options where I live but I’m not sure what the best is in terms of weight as well as durability. Thanks!

zensurfguy · January 12, 2013, 4:12pm

swerfle · January 12, 2013, 5:10pm

I have foiled a few sets of wood fins, and as others have said, plywood is definitely the way to go for a good foil because the layers provide a topographical map to let you see what you’re doing. that said, I also like some more intricate patterns available with solid woods. I’ve been thinking about trying to lam a hardwood design onto a thin ply to get the best of both worlds, I imagine it would make for a stiffer fin too. (If anyone has already tried this I’d love to see the results.)

Anyway, to answer your quesiton about what I use when I foil the fins, I hold the fin in my hand and use a table mounted belt sander to sand it. a this keeps me from getting tired of holding a heavy sander, and allows me to moderate the pressure a bit more delicately. Also, it has two different surfaces to work on, a flat plate and a drum. its a little counter intuitive but the the flat surface of the belt sander allows me to check for flat spots on fin. if the two match up at all, i’m either not finished or I’ve gone too far. If I’m worried about handling the wood too much, I can wear gloves, but I’ll admit, I just like the way a good foil feels in my hand, so I usually don’t. (the innuendo could get out of hand here, so I’d better stop.)

I like pictures so here’s a pretty bad shot of a quad set I made a few years ago:

zensurfguy · January 12, 2013, 10:04pm

Set of cutaway keels with the dark glue , single foiled…

fins · January 13, 2013, 1:04pm

hi zen !

how did the 'cutaways' go , you LIKE them ?

I ask , because a fair while ago now , a guy named 'Mitcho' posted a few shots of some wood ones that HE made [with a back trailer fin , too] ...

cheers

ben