On 3/29/2010 12:08 PM, Keith Nuttle wrote:
I have an oval picture for which I would like to make a frame. I can
draw the oval

As I see it there would be two parts in cutting the oval.
----- The oval cut that would eventually frame the picture.
----- The rabbet cut to hold the picture.

I have the following tools available to me:

1. Table saw (I have no idea how this could be used)
2. Standard size non plunge router with router table.
3. Dremmel with spiral cut bit and other router bits.
4. Jig saw.
5. Drill press with brad point and Forstner bits.

Can I get suggestions making the cutout for the picture.

More Information:

Major axis length (longest "diameter")
Minor axis length (shortest "diameter")
Stock thickness.

One more tool:

Analytic Geometry

Let 2a = major axis
let 2b = minor axis

There will be two foci (on the major axis)

The distance from the center to either focus is sqrt(a^2 - b^2)

The equation, if you want to plot an ellipse is

x^2/a^2 + y^2/b^2 = 1

Or, if you want to construct an ellipse:

push a pin into each of the foci
tie a string to each pin so that if you pull the string taut with a
pencil point, the pencil point will just touch a point at a distance b
from the center on the perpendicular bisector of a line between the two
foci.

It sounds a lot more complicated than it really is

Once you've drawn it, you can freehand rout the opening - and can then
use a rabbet bit to cut for the glass and photo.

FWIW - this project begs for a spindle sander. ;-)

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/