It all depends really, if your running into a triangle or ngon that is stopping a loop from following through, you could always just quad that tri out if it allows your loop to flow in the direction you want it. I manually cut support loops for more complex shapes every now and then, but i always check constrain to edge…
If you're able, can you please post shaded with wireframe screencaps of what you currently have? As one possible alternative to define displacement detail using a base mesh, sculpting complex surface variation would certainly capture an intended result however I think at this stage, will hinder more than be in anyway…
@LouisMarshall Glad the post was helpful. When trying to minimize smoothing based subdivision artifacts, like pinching and stretching, there's two basic strategies that tend to work well with existing geometry: averaging out the differences between the shapes over a wider [preferably flatter] area or constraining the…
@naman Resolving this type of smoothing artifact is a fairly common question and there's a number of different ways to approach the order of operations and topology routing. This thread has lots of great examples provided by the community so it's generally worth the time to have a quick look for how other artists have…
@hututuzhang The distortion is caused by reducing the loops instead of carrying them across the shape. While it is generally possible to manually compensate for this type of shape distortion, some broader context is also required. Catmull-Clark subdivision smooths by averaging the existing vertices. This recursive…
@BladeSharpe looks like you're almost there. Exspanding upon zachagreg's well thought out examples that really is a key aspect to think about or in other words pre-planning prior to modeling anything, will mostly mitigate potential problems from occurring, any how a few additional points to keep in mind: 1. Where possible…
Catmull–Clark subdivision averages between existing points and this creates a smoothing effect. Uncontrolled subdivision smoothing tends to deform shapes and shape transitions that lack supporting geometry. Creating shapes that have crisp edges and minimal smoothing deformation often requires adding support loops on both…
@SkinnyM Have to agree with Eric's recommendation to block out the major shapes before merging them and adding support loops. To add to what's already been said: blending complex shape intersections is all about creating accurate shapes that have relatively consistent segment spacing. Using more geometry can help with…
@Deqa The edges on the model look a bit too sharp when compared to what's shown in the reference images. Though the fender is mostly flat surfaces, there are a number of angled transitions that are missing. Some of which are difficult to see. Gathering some higher quality references, with better lighting and more contrast,…
@Laon A few posts up, there's a couple of relevant examples that cover how to use segment matching to connect a cylinder to a curved surface and how to route the topology around the base of a cylinder that connects to an angled surface. The basic principles of these fundamental modeling strategies can be combined to…