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Tony Bilello
07-25-2008, 11:59 AM
Many years ago I had made an ellipse jig. Well, I forgot how. I remember that I had a board with 2 tracks at right angles to eachother intersecting at the middle. Then there was two sticks that rode inside the tracks and had pins on them.
Thats all I remember.

Thanks in advance.


Tony B

Lee Schierer
07-25-2008, 12:23 PM
Here's a link to one place I found with some photos of a home made jig. http://www.bt3central.com/showthread.php?p=356038There are several commercial versions available. Just do a Google search for "ellipse jig".

Here's another link to a jig for drawing an ellipse.http://mathdemos.gcsu.edu/mathdemos/carpenterellipse/carpellipse_main.html

Wayne Cannon
07-26-2008, 2:44 AM
Here is a link to several different implementations of the same concept:
http://woodhaven.com/Category.asp?Id=33

Joe Scharle
07-26-2008, 8:30 AM
Something like this? The arm has a link for adjusting the size of the oval.

http://www.ncwoodworker.net/pp/data/195/thumbs/DoNothingToy001.jpg (http://www.ncwoodworker.net/pp/data/195/DoNothingToy001.jpg)

Rob Blaustein
07-26-2008, 8:27 PM
One of my buddies is an architect and he asked me that very question yesterday. I dug up a few references for him from Fine Homebuilding and Fine Woodworking. If you have access to these, here are some potentially useful articles:

-The Scribed Ellipse by Jud Peake Fine Homebuilding April/May 1982
-Drawing Big Curves by Paul Schurch Fine Woodworking Jan/Feb 2005
-A Precise Method for Drawing an Ellipse by Frank Fitzpatrick (a reader's tip in FWW #121).

Dick Strauss
07-29-2008, 12:19 AM
Tony,
You can always use the old string and two nails method. The distance between the two nails determines how elongated (eccentric) the oval is while the string length determines the overall oval dimensions. You tape a pencil to the loop of string and trace out the oval while the string always maintains a loop around the nails. If you remove one nail, you have a basic circle jig.

Paul Shinn
07-29-2008, 12:29 PM
Here's a link to one place I found with some photos of a home made jig. http://www.bt3central.com/showthread.php?p=356038There are several commercial versions available. Just do a Google search for "ellipse jig".



Wow! A reference to my jig. Sorry for the bad picture. When I built this
jig, I read the instructions for Rockler's ellipse jig and also watched their
video for help.

http://www.rockler.com/product.cfm?Offerings_ID=17282&TabSelect=Details

There's a graphic in this link that helped me make mine, too:

http://www.woodweb.com/knowledge_base/A_Jig_for_Drawing_or_Cutting_Ellipses.html

Paul