Shell of a model

All throughout the last week, I’ve been trying really hard to focus on getting ready for the CSWA test. Not that I feel ready  right now by any chance, but  I’ve been working on the exercises and tutorials in Planchard’s  Guide.  I must confess that, after reading more than half of Matt Lombard’s book and solving other tutorials here and there, going through the first two chapters of this book  is a bit boring, but absolutely necessary. So far, it is helping me become more efficient and a bit faster, two things that, I’ve been told, are important when taking the CSWA test.

Of course, I must suffer from ADHD or something, because every now and then I just have to take a break, not only to take care of other things I’m also studying,  as well as my kids and the world around me, but also to indulge in some “playtime”. Now, before all the dirty minds out there use their imagination to conjure up some obscure scenes, by playtime I mean simply trying something “new”, at least for me, something that I haven’t done in SolidWorks, some new way to do something, just to see what happens. So, this week I had to be playing and experimenting with the shell feature.

Shell is so much fun to experiment with! All the shell tool does is to hollow a part, leaving open whatever faces you select, and creating thin walled features of the remaining faces. You can even have a model with multiple thicknesses or a hollow model with no open faces. 

At first, all I could think of were hollow models that reminded me a bit of my little son’s play-dough molds.  On a square block, I created a few features and then hollowed the part with one single thickness, removing the bottom face (Face< 1> in the dialog box).

This is the result, as seen from the inside.

The extrusions and the sweep have been hollowed out following their shapes, and they now look like cut features from this side of the model. One of the cuts, the one that went through the whole block, looks now like a thin walled cylinder. The other cut wasn’t deep enough to reach the face that was eliminated, so it got to keep its bottom face.

Well, so far I knew I could create play-dough molds, boxes, bottles and cups, but what else can this tool do for me? These are a couple of models I came up with by applying the shell tool.

First, I created an extrusion, applied some draft to it, and filleted the edges. It’s important to fillet the edges before using the shell tool, or else they may fail or you may at least end up with areas of unequal and unpredictable thickness. Believe, I’ve been there and done that! After that, I used the shell tool and removed the top face, to create a hollow box with round edges inside and out.

Then I added a couple of ribs, also with some draft, to divide the box into four smaller ones. I also applied a few fillets to the edges on the inside.

Last, I applied the shell tool again, but this time I eliminated the bottom face and all the other ones around it, like you can see in this image. All the faces colored in green are the ones that are left open.

The result of applying the shell tool this second time is shown in the following image.

For my second experiment, this time I started with a circular extrusion, adding some draft, and applying the shell tool, to create a cup.  Next, I added a rib feature and reproduced it three more times in a circular pattern around the Y axis. I also added a few fillets. This image shows how it looked so far.

Last, I applied Shell for a second time, choosing to eliminate (or leave open) the face on the bottom and the outside face of the cup.  This image shows the selected faces in green.

The result reminds me a bit of the bottom part of some 2 Lt. soda bottles, doesn’t it?

What other creative uses are there for the Shell feature? What do you do with it? Please, do share!