BACKGROUND:

Earlier this week, we had a customer with several design problems. As could be expected, SolidWorks provided a timely and efficient solution. First, they needed a sheet metal part that had a specific top profile. The reason for this was that it had to fit in an assembly between several other components. From the top, the part had to look like this:

In most cases, this would be a simple task. Create a sketch that matched this top profile and use the “create base flange/tab” feature to extrude this a given distance. The other option would be to create a
base flange/tab and create an edge flange off each side. It should noted that the critical dimensions of the drawing are the dimensions from the first view. Seeing the part from a side view, you can see there also needed to be an angle cut as shown:

MANUFACTURING LIMITATIONS

If the only issue was that they needed to know precisely what the folded model looked like, there would be no problem. Any sheet metal modeling software could create a part for them. The problem was that because this part was so large that there were manufacturing limitations on cutting the blank. As it turns out, the limitation of the manufacturing tools made it necessary that all of the cuts to the blank would have to be straight lines. Here the task put in front of SolidWorks was to build a part that met specific folded profile dimensions, (see top view), but have this profile be able to be cut from a part blank that contains only straight edges (when unfolded). The customer needed to know what the geometry would look like precisely when folded, given their specific manufacturing limitations, so that they could accurately see if there was any interference in the assembly.

SOLIDWORKS PROVIDES A NO GUESSWORK SOLUTION:

SolidWorks provided a timely no guesswork solution by using the “unfold” and “fold” command found in the sheet metal tools. What makes these commands so powerful is that it allows us to first flatten, add features (in the flattened state), then re-bend the part according to the original specifications. After creating the vertical profile, we used the “unfold” command to essentially roll back the piece to its unbent state. After making a triangular cut to the flattened piece, we used the “fold” tool to re-bend the part.

Using the “unfold/fold” command, SolidWorks managed to eliminate the guesswork that often is associated with making models that are based on real world manufacturing limitations. Below we have a final drawing of the bent part. Notice the angle variation going from the left to the right side of part. Had we done a simple extruded cut on an already folded part, we would not have been able to account for the change in angle in the transition section of our piece. Again, SolidWorks provides a fast and efficient modeling solution.

Above a drawing of the blank and below a side view of the folded part:

This entry was posted on Friday, January 30th, 2009 at 3:58 pm and is filed under Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.