Hello I’ll be handling the critique for your 25 wheel challenge.

-Starting with the structure of your wheels I noticed that in many cases you’ve laid a simple straight cylinder for them, it is important that you add a subtle bump in the midsection, this will make the wheel look inflated, which is an important aspect as they are filled with air and aren't as rigid as they may seem.

When I was working on this challenge I do remember looking at some wheels that looked completely flat, but regardless, always try to add a larger ellipse to imply the presence of this bump.

-When it comes to the other structural elements like the spokes/rims you do seem to be implying the presence of their side planes to make them look more solid. There are a few instances wher you don’t do this and there are others when you rely on form shading,

This form shading, where you're making a surface lighter or darker based on its orientation in space - should not be included in our drawings for this course. Instead, you'd be drawing the outlines for the entire 3D structure, defining the edge between the side plane and the front/outward face, and reserving filled areas of solid black only for cast shadows.

-This challenge serves to reminds us of some of the things we learned in lesson 2 texture section. In your case I think we are getting some mixed results, there are definetely some cases where you have decided to draw the texture details explicitly, a really good example would be number wheel number 7 and number 15, where all of the textural shapes edges are clearly outlined.

While doing this is not necessarily bad, as it can help you to be more aware of how this forms wrap around a surface, this kind of small details tend to pile up and drawing them explicitly results in a lot of visual noise and clutter. That’s why we decide to draw them implicitly using cast shadows.

When you draw them keep in mind the form casting the shadow and also take some time to design its shape, and think about how it wraps around the surface it is falling on.

Here is a diagram that actually explains this point pretty well https://imgur.io/SEwsEfO , on the top you have the textural form with its outline and planes drawn explicitly, and below them on the second row you have the side planes filled with black which falls under the category of form shading, on the right you have the cast shadow example hich is the correct one.

-On the other hand you are also making use of simple lines to draw the texture of the tyre. It gets trickier here because we'll often mistakenly think about the grooves themselves as being the textural forms in question - but that is not the case. Grooves, like any other holes (like in a sponge texture) are not forms - they're negative space, empty space, and the forms in question are actually the walls surrounding them. This diagram helps to explain the distinction. https://imgur.io/SCnATRK

Okayy I’ll go ahead and mark this lesson as complete, though make sure to review the texture section on lesson 2 if you need a reminder.

You're almost done just one more lesson!!