CompuServe Messages

Michael, If your tube is odd-shaped, i.e. it curves in weird ways, there doesn't seem to be an easy way out, as in: rotate the object so a clean cross-section appears in one of the views, zoom in, and use the Shift key along with the lasso to circle all outside or inside faces. Perhaps you should've split your object while it was still a few primitives; for example, if the tube is a flat, hollow disk, extruded along a roller-coaster path, you could've split the outside and inside edges of the disk into separate objects before extruding. Extruding both objects along the path would've resulted in a perfectly matched pair of objects, each of which could've been given the proper attributes. Finally, if your pump housing was built out of several primitives, you could've used the previous technique as each primitive was added. Regarding screw threads, can you give us a better idea of what your tube looks like? Is is a simple, straight tube? If so, follow this procedure: 1) Add an axis. In the top view, add 4 lines like this: _ | | \ | Distance = 20 units, for example | | + / _| axis 2) In Pick Objects or Pick Groups mode, pick the axis and Extrude along Y for 10 * 20 units (200 units), with a Y rotation of 10 * 360 degrees (3600 degrees). This will spin the profile you drew and create a screw shell. The ends, however, will look ragged. 3) Position a flat disk 20 Y units into either end, select all objects, and Slice. Remove excess material from disk and screw. This will clean up lonely polygons at one end of the screw, and add a cap made from the center part of the disk. Do the same at the other end, or add a hemisphere to make the screw head. (Slice a small slab shape out of the hemisphere to create the groove where a screwdriver would fit) Alternatively, when extruding you could've entered zero as X and Z final scaling [ MORE ]