cutting and foiling fins

thanks to some great info on here ive made my first few set of fins,they seem pretty good! what ive found is cutting them out using a jigsaw destroys the blades unless i cutt really slowlly,is anyone using a scroll saw or similar? also foiling im using a mix of grinder/powered sander/ by hand.......any ideas chaps?

Use a carbide grit blade, for cutout, then grinder, sander, hand!   You're doing it right.

thank you!  mmm maybee my budget blades arnt up to the job!some jobs are a bit tough..then again so is coughing up 40 ish quid for a set of fins! 

Bandsaw is the best cutout tool. Otherwise the carbide jigsaw blades (as BT suggests), but they cost almost exactly the same times as many $ as they cut fins vs regular metal-cut blades. Unless there's some new miracle-blade I haven't seen...

when you say bandsaw,how industrial are we talking? when i said scroll saw i was thinking along the lines of a hobbyist type thing....

The bandsaws I've used are full-size. Cutting a fin sheet is comparable to aluminum of same thickness, you might be able to reference the capacity of the scroll-saw from that.

Hey gix' skip the scroll saw idea and scrap the jigsaw - quit rattling you brains out and chipping the blank all to hell.

 Like Mike says, the best, fastest, cleanest tool for cutting fin blanks is a band saw.  Nothing fancy or industrial. I see smaller used ones (7") on Craigslist all the time for $25-$50.  Get one of those and a 1/8" wide blade, and you'll be in fin heaven.  Another trick I use for cutting out blanks is the ol' spiral pattern bit on the router table trick.  If you're cutting out multiples of the same fin, make one pattern out of 3/4" mdf or ply, and glue some grip foam on both sides.  Rough-cut your blank then trim exactly to shape with the router - no sanding to match the edges.

 

 

As far as foiling goes, get a 3" hook and loop (velcro) sanding pad and some 80 grit discs for the angle grinder.  The disc is small enough to finess some good foils out of your blank before blending the contours with 120 grit on an orbital sander. 

Now if you really want to "git-r-done" but can't afford to go the CNC route, build yourself a manual pantograph (take a look at some youtube videos). 

Hope this helps. Good Luck.

 

Use a tooth density so that there are three teeth across the width of the material…and use bits made for cutting metal, not bits made for cutting wood. A jigsaw is fine but a nice bandsaw rocks. Foil with 24 or 80 grit on a 3-4.5 inch pad on an angle grinder (I never used a 3 - but now am intrigued). An old friend puts his angle grinder in a vise and holds the fin to foil - he’s done thousands that way. I hold the grinder and put the fin tab in a vise…

nice one! yeah i like the idea of the router table,and ill try metal blades in my jigsaw too.....a set of my fins has just gone to a shop owner for testing,and while i was down the beach today i noticed one of my boards that i dropped off in the shop ealier in the week,the lad that brought it loves it and was stoked to met the shaper! i think the proceeds from that one will fund some fin experiments...once again,thanks for the tips!

Make yourself a nice cheap stand to make things easier on your back and arms. I made this in a few minutes and got the pliers from the swap meet for 3 dollars. Hope it helps. Mines a littel more tricked out, It spins around with the knob to tighten on top. But you can make something similar pretty cheap.

 mjd102.jpg picture by neptune1970

nice one,i like that,ive got a small vice that turns 360o  that will surfice..come on then people..lets see some fins!   oh and on another similar topic id like to make a freind of mine a longboard fin for he's birthday..i was thinking of cutting/shaping the fin as normal then sitting it in a "box" of resin containing the pin(if you know what i mean) im pretty sure pu resin on its own wont do,so what about epoxy or mixing pu with micro ballons or something? sorry if this has been done before..

that fin-sanding stand is an awesome idea. Every day I see something on here that’s beautiful and simple and makes me go “Why didn’t I think of that?”

As for fin-making, I started reading and then got sucked into the rabbit hole of hydrodynamic theory as applied to fins in this thread: http://www2.swaylocks.com/node/1010225

This thread is awesome too: http://www2.swaylocks.com/node/1014783

(You guys have probably read all this stuff before because it’s required reading here, right? I’m new here so I don’t want to step on anyone’s toes by pointing out stuff that’s already been read to death. I guess I was just amazed by the depth of thought into such a seemingly minor part of a surfboard. I used to think it was minor but after today, I won’t take fins so lightly again.)

neptune197037 - that is a brilliant stand, do you have a higher-res pic to post so we can study it in all of its glory?
Thus far I've clamped fin material to a work bench, which is pretty Flintstones-simple, but of course the clamp gets in the way as you foil.
Some folks bolt smallish vises to the wall, then clamp down on fin material.
Bench sanders are really nice for cleaning up fin outlines and even for foiling the fins themselves. Just mind your fingers!

Here is some more detailed pics. I have since tried to add a tray on top for paper and such.

sways3.jpg image by neptune1970
sways2.jpg image by neptune1970
sways1.jpg image by neptune1970

that fin stand is a great idea!

just wondering if anyone was else was taught cut there fins out with a templete and stanley knife just as the resin started go off?