I want to mill a 10* angle on the leading edge of a skid fin for my model
boats. The lead angle of the fin is 30* and I need the 10* "wedge" parallel
to the water line so the fin doesn't cause lift.

I think there's compund angles involved but I just can't see the setup,
here's some pix of what I'm trying to do:

http://gallery.intlwaters.com/displa...lbum=988&pos=0

http://gallery.intlwaters.com/displa...lbum=988&pos=1

Here's what it looks like in action:

http://gallery.intlwaters.com/displa...lbum=988&pos=2

The fin is that bit hanging off the right front sponson.

Any ideas?

--Well the two things that come to mind are grinding it freehand
(the way surfers make fins) or making a mold with that shape already in it.
Neither one is trivial, but it's a whale of a lot easier than trying to mill
that kind of shape without a cnc..

--
"Steamboat Ed" Haas : Dare me to
Hacking the Trailing Edge! : make less sense...
www.nmpproducts.com
---Decks a-wash in a sea of words---

On Mar 28, 9:59*am, "Terry Keeley" tkee(no wrote:
I want to mill a 10* angle on the leading edge of a skid fin for my model
boats. *The lead angle of the fin is 30* and I need the 10* "wedge" parallel
to the water line so the fin doesn't cause lift.
...
Any ideas?

How about drawing a line on the part parallel to water flow and
tilting that line to 10 degrees?

It might be easier to place a 10 degree angle gauge on the line and
level the top.

Jim Wilkins

Thanks for the reply's guys, not sure I follow though...


"Jim Wilkins" wrote in message
...
On Mar 28, 9:59 am, "Terry Keeley" tkee(no wrote:
I want to mill a 10* angle on the leading edge of a skid fin for my model
boats. The lead angle of the fin is 30* and I need the 10* "wedge"
parallel
to the water line so the fin doesn't cause lift.
....
Any ideas?

How about drawing a line on the part parallel to water flow and
tilting that line to 10 degrees?

It might be easier to place a 10 degree angle gauge on the line and
level the top.

Jim Wilkins

Terry Keeley wrote:
I want to mill a 10* angle on the leading edge of a skid fin for my model
boats. The lead angle of the fin is 30* and I need the 10* "wedge" parallel
to the water line so the fin doesn't cause lift.

I think there's compund angles involved but I just can't see the setup,
here's some pix of what I'm trying to do:

http://gallery.intlwaters.com/displa...lbum=988&pos=0

http://gallery.intlwaters.com/displa...lbum=988&pos=1

Here's what it looks like in action:

http://gallery.intlwaters.com/displa...lbum=988&pos=2

The fin is that bit hanging off the right front sponson.

Any ideas?





Is this like a knife edge, or just 10 degrees on one side? By 10 degrees
parallel to the waterline, I assume you mean the angle intersecting the
waterline is to be 10 degrees included.

--
Steve Walker
(remove wallet to reply)

" Is this like a knife edge, or just 10 degrees on one side? By 10 degrees
parallel to the waterline, I assume you mean the angle intersecting the
waterline is to be 10 degrees included.

--
Steve Walker
(remove wallet to reply)

It's just 10* on one side, a wedge really.

I think I figured it out. If I tilt the head on the mill 30*, set the turn
fin up with it's LE parallel to the table then tilt it 10* in the "y"
direction, it should work if I cut in the "x" or longitudinal direction.

I'll post a pic. when I get to it tomorrow or Monday...

Here's the setup:

http://gallery.intlwaters.com/displa...lbum=988&pos=3

Now I've got a perfectly flat 10 degree wedge, just what I wanted!

Thanks for the help!