Using a 005 fineliner is fine, although most students are in the same boat as you, and manage to work with ballpoint - so it really shouldn't have been as bad as you may have expected. That said, your assumption that pencil was okay is incorrect, and given that you're this far through the course, you probably should have expected that. It's one thing to reach for a smaller fineliner when students are given permission to use other kinds of pens, but pencil is very much not allowed, nor are any kinds of underdrawings, and this has been established earlier in the course.

Anyway, starting with the construction of your wheels, for the most part you've handled it well, save for two main points:

• This isn't an issue across the board, but there were definitely some (like 20 and 23 to name a couple) where your tire was very straight all the way through its length. This may be accurate, but generally speaking standard tires will have a bit of a widening through the midsection, which makes them feel more 'inflated', rather than being stiff like a simple tube. So for example, 19 was a better example of this being done well.

• You appear to have forgotten the distinction between what constitutes a cast shadow and what constitutes form shading, so you've been filling in a lot of the side planes of your structures with solid black, which is essentially capturing form shading. This, as described here, is not meant to play a role in our drawings for this course.

Aside from that, I'm also pleased with how you've approached your rims - while filling in their side planes with black definitely flattened them out by putting the focus only on the front face and splitting it into two separate parts, rather than a single cohesive form, it does still show that you're conscious of the fact that those rims - thin as they sometimes are - have thickness to them.

Moving onto the tire treads, here you've sprung a trap. See, the wheel challenge is so far removed from the distant days of Lesson 2, that it's actually very common for students to forget about the points that were raised there, specifically in the texture section. But, given that tire treads are just a series of forms arranged along the surface of an existing form, they absolutely fit the bill of a 'texture' and thus we should be capturing those textural forms through the use of implicit marks. Meaning, by defining the shadow shapes they cast on their surroundings, without actually outlining the textural forms themselves at any point.

From what I can see, you certainly have made an effort to work with larger filled areas of solid black, but the specific way in which you've used them is pretty arbitrary. There's a lot of outlining and a lot of form shading (although as you noted, no ability to create a gradient to capture the value ranges that are generally required for form shading). In number 21, I can also see you filling in the gaps between your textural forms. But none of this actually establishes the relationships between the textural forms and their surrounding surfaces in the manner that cast shadows do, and so a lot of the textures come out looking flatter than they otherwise could.

The reason we focus so much on implicit marks is because they allow us to control the density of detail without changing what is being conveyed to the viewer. These wheels work fine floating in the void on their own, but as soon as you slap something like number 15 with its densely packed linework onto an actual car, you're going to create a focal point at the wheels, drawing the viewer's eye to it whether you mean to or not.

Cast shadows however are subject to light - we can place a brighter light source to "blast away" the cast shadows if we want a much sparser, lighter texture and draw less attention to it, as demonstrated here (it's not a tire, but the concept applies all the same).

It's not uncommon for students to attempt the implicit markmaking/cast shadow thing but, like you did in number 17, use their filled black shapes incorrectly by filling in the side planes of those textural forms, running into form shading instead.

Here's an example I provided to another student who ran into this issue. On the top, we've got the structural outlines for the given form - of course, since we want to work implicitly, we cannot use outlines. In the second row, we've got two options for conveying that textural form through the use of filled black shapes. On the left, they fill in the side planes, placing those shapes on the surface of the form itself, and actually filling in areas that are already enclosed and defined on the form and leaving its "top" face empty. This would be incorrect, more similar to form shading and not a cast shadow. On the right, we have an actual cast shadow - they look similar, but the key point to pay attention to is shown in the third row - it is the actual silhouette of the form itself which is implied. We've removed all of the internal edges of the form, and so while it looks kind of like the top face, but if you look more closely, it has certain subtle elements that are much more nuanced - instead of just using purely horizontal and vertical edges, we have some diagonals that come from the edges of the textural form that exist in the "depth" dimension of space (so if your horizontals were X and your verticals were Y, those diagonals come from that which exists in the Z dimension).

The last thing I wanted to mention is that when we deal with tires with a lot of tight grooves (like 15), we can often get away with light, tapering lines. 15's definitely too heavy in its use of ink for that, but 16's a better example. But while the wheel itself might look okay (in that it's not drawing too much attention), the thinking behind it is still incorrect, because we're focusing on the grooves themselves - the negative spaces, the gaps - which are not textural forms. They're empty space. The textural forms in question are actually the walls around them, which cast shadows into the grooves, upon the surfaces of their "floors". Here's a diagram that gets into how to think about this.

Fortunately, this trap has been laid intentionally to provide a bit of a reminder to students, not to punish them. So, I'll still be marking this lesson as complete, but you'll definitely want to reflect on the Lesson 2 texture material. So, I'll go ahead and mark this lesson as complete.

If anything, the bigger mistake really was using pencil to create underdrawings - I know that you've been away from Drawabox for a while, but you may want to avoid making any such assumptions going forward. Stick to the instructions to the letter, and if you're uncertain, ask.