How to work with assembly sketches in SOLIDWORKS – part 1
Welcome back. I’m continuing my discussion of working with assemblies in SOLIDWORKS. When you use a SOLIDWORKS assembly sketch, this is one technique for creating a top-down assembly.
So, what’s a top-down assembly?
First of all, what does the top-down approach mean? Not mysterious. Top down means you break down something into smaller pieces, but the first thing you do is start with the overall way you want the parts of your model to fit together. This way of designing works better for some people and for some models. You start with the big picture and break it down from there into the base elements–parts, features. The bottom-up approach works the other way: you start with the individual pieces and then fit them together in the Assembly environment. You start on the Sketch tab, then work your way to the Features tab, and then get to the Assembly tab. In a bottom-up approach, the individual base elements of the system are first specified in great detail. These elements are then linked together to form larger subsystems, which then in turn are linked, sometimes in many levels, until a complete top-level system is formed. But with a top-down assembly, you start out on the Assembly tab, though you still have access to the functions and power of the Sketch and Features environments in SOLIDWORKS; there is no limitation.
When you’ve decided you’re going to work top-down, you will begin your assembly with something like a layout sketch that guides the geometry and dimensions of your features, their placement together, etc.
What’s an example of how this works? Let’s say you’re building a circuit board. You need to cut a hole for a screw, but instead of choosing a distance for the depth of the extruded cut, you use the Up to Surface option. Thus, the dimension of this feature is defined in relationship to other parts in the model. If you move parts around later, the fit will still be ok.
Solidworks tutorial Assembly Sketch 1 – posted on youtube by VTN -Rosanna D