## Thursday, 30 January 2014

### Surface Modeling Pep Backrest

 This tutorial shows how to make a Backrest using the cross curve tool. This tutorial also demonstrates bending an Closed Curve with a hole - a Scooty Pep Backrest.

Index of all Solid Edge tutorials on this blog is here.

Disclaimer:
• This tutorial and the steps illustrated herein are by no means claimed to be the best or the only way to create the given design.
• This tutorial is an attempt to introduce and demonstrate the awesome set of tools that Solid Edge has for curve creation and surface manipulation.

 Front View Curve Begin by creating a curve in the x-z plane.
 Front View Curve - Normal View When viewed in the sketcher, the curve would look something like as shown in figure. Apply tangent relationship to all connected curves. Here, the dimensions or even the form of the backrest is not important. This tutorial shows you the approach to create the backrest. You may go out into the parking and take actual measurements.
 Top View Curve Create another curve (an arc) in the x-y plane. See figure.
 Top View Curve - Normal View The Top view curve may extend beyond the limits of the front view curve drawn earlier. But in no case should the new curve fall short of the extents of the earlier curve.
 Cross CurveSelect the Cross Curve command from the Surfacing toolbar as shown.
 First CurveSelect the top view curve as the first curve. Click accept     on the ribbon bar.
 Second Curve Select the front view curve as the second curve. Click accept     on the ribbon bar.
 Cross Curve Click Finish on the ribbon bar. Soon the cross curve is formed. The cross curve is neither in the top plane nor in the side plane. It travels in 3D space, giving us the desired curve to create the backrest. In other words, the front view curve is effectively bent by the top view curve.
 The Bounded Surface Hide all sketches. Click the Bounded Surface command from the Surfacing toolbar. Select all the edges of the cross curve by dragging a window around it. Click Finish on the ribbon bar. A surface will be formed from the edges.
 Sketch in Parallel Plane Create a sketch in a plane parallel to the y-z plane as shown.
 New Sketch Normal View The curve extends outside the right part of the bounded surface. See figure.
 Project Curve - Curve Step Select the Project Curve   tool from the Surfacing toolbar. Select the sketch as the curve to project. Click accept     on the ribbon bar.
 Project Curve - Body Step Select the bounded surface as the surface to project on.
 Project Curve - Direction Step Point the arrow down towards the surface and click. Click Finish on the ribbon bar.
 Project Curve - View It If required, click the Visible and Hidden Edges   tool on the Main toolbar to see the projected curve.
 Trim Surface - Surface Step Select the Trim Surface   tool from the Surfacing toolbar. Select the bounded surface as the surface to trim.
 Trim Surface - Curve Step Select the projected curve as the trimming curve. Click accept     on the ribbon bar.
 Trim Surface - Side Step Indicate the arrow pointing downwards as the part to trim off. See figure.
 Surface Trimmed The bounded surface is trimmed as shown in figure.
 Surface to Solid Click the Thicken     tool on the Features toolbar. The Thicken tool is in the same flyout as the Thin Wall and Thin Region tools. Select the trimmed bounded surface to thicken. Use an appropriate value to thicken in any direction. Round off sharp edges of the backrest and mirror the half part to complete the backrest. Equally simple and interesting is creating your own, brand new, fully functional CAD system with 3D sketching and surfacing capabilities using a geometric modeling kernel.cMayoCAD from CADVertex is one such program.Download the detailed course contents for cMayoCAD here.