This article covers fundamental best practices of subdivision modeling using a support loops system. It will specifically cover support loops.
In this article we will be looking at this example model:
As we can see, the model does have support loops running around the perimeter of the form, however they are extremely tight and there is only one loop. This sort of looping is referred to as “micro bevels” and is typically regarded as a bad practice. Constructing a model using micro bevels renders it unserviceable: iteration would require reworking a lot of surfaces and pulling back many edge loops just to get a decent read. There will also be problems with evenly adjusting these loops at corners such as the two near the bottom right and bottom left of the object, as edge sliding tools tend to get sticky in these areas.
So from here we will rebuild this model using best practices. The primary shape will be the focus for this article.
The primary underlying shape.
There are certain edges on this model that I would refer to as "profile edges," basically all the edges that make up the silhouette of the form. Taking away any of these profile edges would change the silhouette. In the image below, the bold edges are the profile edges. These are the ones that need to be reinforced with support loops on both "sides" in order to maintain a similar form when subdivided.