1. What 3D objects are represented by a pair of concentric circles in its plan (viewed from above) and a pair of concentric circles for its front elevation (vertical face)?

2. What would a #1 object be if it also has a side elevation that is concentric squares [with corner diagonals]?

Imagine a right cylinder, radius and length R.  Colinear with the centerline of this cylinder, and at the exact center, is a cylidrical void of radius and length r, where r<R.

Take 2 two these objects (exact same R & r), and cause them to intersect such that their center axes form a 90 deg angle, and those axes intersect at the center of each object. In other words, the centers of the two outer cylinders are superimposed as are the centers of the two smaller cylinerical voids.

The problem is then to "erase" the outer intersection lines from by the outer surfaces of the two ctlindrs.  These would sho up as lines in various views  You do this by "cutting back" each of the outer sylinders to the surface of the other to form a common smooth surface with no corners or edges.  The remaining solid, I believe would have the properties required by Part 1 & 2.

Note:  I propose we try to solve this without the aid of CAD software to visualize results

Edited on August 19, 2006, 9:27 pm

Posted by Kenny M on 2006-08-19 21:23:49