Calculations for a Using an ECF

Use this for designs where the ECF cut diameter is < the pattern outside diameter (R2 < R1). Calculations needed for this are based on the data in the table below.

Input fields are  colored .

R1 radius		in	Outer radius of the pattern
Patterns			Patterns to cut around the circle
Overlap			Overlap of the patterns (0=abutted; 1=50%; 2=33%, ...) 0 overlap = Abutted 1 overlap = 50% 3 overlap = 25% Click on any pictures above to see larger versions.
Indexing		°	Angle of indexing between patterns.
R2 radius		in	radius to set the rotation of the ECF.
R3 radius		in	Radius to move for the center of rotation of the ECF.
R4 radius		in	Inner radius of the pattern

Calculate Values

Using This Data

1. Set the Eccentric Cutting Frame to rotate with radius R2.
2. Set the axis of rotation for the Eccentric Cutting Frame at radius R3 away from the center of the piece.
3. To test your setup:
   1. Cut one circle.
   2. Rotate the piece 180°.
   3. Cut another circle.
   4. The distances between the inside edges of the circles should equal R4.
   5. The distances between the outside edges of the circles should equal R1.
   6. Adjust as necessary to achieve the desired effect.
   .