To design the housing for the Wankel housing you first have to establish the eccentricity.

In this plan we will make the eccentricity one half inch, and the rotor a six inch triangle. Visualize a one inch diameter watch face with 45 successive minute marks starting at the 9 o’clock position and finishing at the six o’clock position.

Each clock minute is exactly six degrees of a 360 degree circle. 9 o’clock is at the 45 minute position. Count from this backwards in a clockwise direction until you have numbered all the minute marks ending with 0 at the six o’clock position.

Draw a horizontal line with a space and a point ending exactly at three inches starting at the 9 o’clock position. The point at the end of the line will be exactly at the minor axis of the housing.

Draw a horizontal line with a space and a point ending exactly at three inches starting at the 44 minute position, then rotate this line two degrees clockwise. Two degrees is one third of the starting point rotation..

Draw a horizontal line with a space and a point ending exactly at three inches starting at the 43 minute position, then rotate this line four degrees clockwise.

Draw a horizontal line with a space and a point ending exactly at three inches starting at the 42 minute position, then rotate this line six degrees clockwise.

Continue this exercise until you have used all the designated minute marks and have a horizontal line with a space and a point ending exactly at three inches starting at the 0 minute position then rotate this line ninety degrees clockwise.

What you will find is a line of dots that make one quarter of a precision Wankel type engine housing.

My experience shows me that Mazda is not aware of this type of precision.

Hope this is of interest.

Ken McKenzie