Tapered Fins Using Hand Tools

I'm not big on build threads, but thought others may find my methods interesting. I'm building a half-scale standard Aerobee, and the vehicle calls for fins that are tapered from root to tip and have a curved bevel on the leading and trailing edges. This complex shape can be done many ways, but I enjoy woodworking and using hand tools whenever possible. For my fins, I am using nothing more than a Stanley spokeshave, a Shinto rasp, and sandpaper. Power tools be damned! See below.


I'm doing a composite fin. I started by laminating a .062 G10 core between 5/16" balsa sheeting from Specialized Balsa (great people!). Balsa is cheap, shapes easily, and is light so it was an easy choice. Eventually, the fins will get two layers of CF and one layer of light glass. Here is the first one cut to shape, before tapering:


Next, I outline the taper with a pencil.


Then go at it! I keep an eye on the pencil line and get into a "rhythm" with the spokeshave. Few things are more satisfying than a finely-tuned spokeshave!


After about 10 minutes and some very light sanding, I have finished one side. Not bad, eh?


Taking a break for lunch, then I'll do the other side (which will be easier since I've already got one side tapered to "mirror." Then I will use the shinto to do the beveling.

Tapered the other side.


Pencil line drawn to indicate bevel start.


Bevels cut with rasp and sanded.


Both sides beveled.


Rounded the corners with a file. Two completed today. Will finished the third fin this week and then laminate all with CF cloth.



Things to come...

Beautiful work. I lack both the know how and patience to do such things. Again, very nice!

Very nice work! I'm also a fan of balsa for shaped fins. Easy to work and (mostly) non-toxic.

I don't have the touch for making the shapes consistent by hand, but one can also use a jig:
https://jcrocket.com/nike-tomahawk.shtml#sustainerfins

Thanks, Cl and John. Hand tools do require practice but can be just as consistent as other methods. Faster, too, I believe. I bet I could finish all three fins by hand in the time it would take to build a jig for this particular profile.

John, I've spent hours over the years looking at the techniques on your site. Thanks for keeping that great info up!

Those are very nice fins ,I like them !

And indeed ,there just is something about wood and handtools....very ZEN !

I need a new spokeshave ,mine is just worn out ,as it`s such a handy tool.

Paul T

I realize I never posted pictures of the finished product. She flew at Springfest in Las Vegas last month on an M.

Cl(VII) said:

Beautiful work. I lack both the know how and patience to do such things. Again, very nice!

Click to expand...

hear hear!