Tools - like the french curves and ellipse guides - all have their limitations, or more accurately, their intended uses. A 65 degree, 1.5inch ellipse from an ellipse guide will be intended for drawing that particular kind of ellipse, and not a 75 degree, or 1.25inch ellipse, etc. That is ultimately what makes getting a full ellipse guide best in terms of having more cases where the tool can be used instead of freehanding, but given that a full set can easily cost upwards of $100, that's not an option for most students.

We certainly allow students to use those tools here, and encourage their use where applicable, but rest easy - most students end up freehanding the majority of their ellipses for this lesson, for the same reason as you. They've mostly only been able to get the far more affordable "master" ellipse template. Fortunately, when this course really benefits from ellipse guides, that master template provides everything that's necessary - and that is for constructing the bodies of our wheels in the wheel challenge, and for applying the "constructing to scale" technique from Lesson 7 where we leverage the relationship ellipses have with squares in 3D space (as introduced in the cylinder challenge) to create 3D unit grids that follow very specific proportions.

Everything outside of that can still be freehanded, and it won't be a big problem for you getting as much as you can from these lessons.

Anyway! Jumping right in with your form intersections, you've done a fantastic job and have demonstrated a very strong, well developed understanding of the relationships between these forms in 3D space. At this stage, we actually don't expect quite as much as that from students - rather, we expect them to be now comfortable with intersections involving forms with only flat surfaces, but to still struggle when curving surfaces are included. That does not appear to be a problem for you, however.

I did catch a couple smaller issues, which I noted on this page and on this one, but note that I am nitpicking - looking for smaller issues to call out, in the absence of those large ones I would usually focus on. The issues are primarily:

• Your use of line weight being somewhat hesitant - you may want to review this material on the application of line weight from Lesson 1, but at its core, remember that when you execute those marks, no matter how afraid you are of going off track, you still need to be executing them with confidence. You may miss the mark, but exercises like all of those throughout this course are not about the drawing you're producing in the moment, but the long term gains the exercise itself will imbue when applied over a long period of time.

• For the pyramid-cone intersection, I think you may have gotten confused about which side of the pyramid was facing the viewer, although the other interpretation would have the pyramid coming up towards the viewer, which would have it intersecting with the rear of the cylinder (which we can't see). That said, given that pretty much all of your other intersections demonstrated a strong grasp of spatial relationships, I'm going to chalk this one up to a momentary confusion. If you notice a situation where things just stop making sense to you, a good approach is to take a step back from it and come back with fresh eyes. Many students end up ploughing through but this is more likely to result in choices that don't really hold up to scrutiny.

• And on the second page, this was a much milder case where the intersection line wasn't oriented quite right - close, but it suggests a smaller angle difference between the orientation of the box vs the cone than was merited by how the forms were drawn.

Now, I pretty much always share this diagram with students at this stage, because they're generally in a position to benefit from it. It demonstrates how we think about intersections in pairs of surfaces, and how the orientation of one will determine which cross-section of the other is relevant to that paired intersection. It also tries to take a different approach to curving surfaces by describing them in relationship to an edge that can take a very sharp turn from one surface to another, or it can be made more gradual, turning into what is effectively just another curved surface. I believe these are both concepts you are entirely comfortable with, but I'm including the diagram here because I figure it wouldn't hurt, and if it helps solidify those concepts further for you, then all the better.

Continuing onto your object constructions, aside from your application of line weight being more aggressive (which is addressed in the line weight material I linked you to above in regards to your form intersections) - I know you mentioned switching between blue ballpoint and fineliner early on, but the line weight issue is present in your later constructions as well to a milder degree - just about everything else is really well done.

It's very clear that you've taken the concepts from the lesson, which serve as tools to help promote an increase in precision and control of the construction itself and how it unfolds, and applied them to great effect. Precision is often conflated with accuracy, but they're actually two different things (at least insofar as I use the terms here). Where accuracy speaks to how close you were to executing the mark you intended to, precision actually has nothing to do with putting the mark down on the page. It's about the steps you take beforehand to declare those intentions.

So for example, if we look at the ghosting method, when going through the planning phase of a straight line, we can place a start/end point down. This increases the precision of our drawing, by declaring what we intend to do. From there the mark may miss those points, or it may nail them, it may overshoot, or whatever else - but prior to any of that, we have declared our intent, explaining our thought process, and in so doing, ensuring that we ourselves are acting on that clearly defined intent, rather than just putting marks down and then figuring things out as we go.

In our constructions here, we build up precision primarily through the use of the subdivisions. These allow us to meaningfully study the proportions of our intended object in two dimensions with an orthographic study, then apply those same proportions to the object in three dimensions.

Your thorough use of those orthographic studies has been very effective, and I can clearly see how much effort you're putting into making decisions in the orthographic plan - which is exactly right.

There's just one additional thing I wanted to offer, which isn't relating to any significant issues or mistakes, but more additional context to the use of hatching that you see in the bluetooth speaker demo - where I use vertical lines at the rounded corners, and which you may have applied to some degree in areas like the water bottle (with the very thick stripe of black), the water bottle lid, and the bluetooth airbuds case.

Basically what I'm doing in that bluetooth demo is taking a corner that, by virtue of being a corner, is naturally going to be interpreted more as a sharp corner than a rounded one, especially with my bounding box resulting in a clear edge there. I rounded it out in my construction, but because the sharp edge is still present, it's likely to create some visual confusion. By adding the hatching there, I'm essentially reinforcing the curved part of the construction.

Where this generally isn't really needed is when the structure is already fairly close to a primitive - like a cylinder - where the surface is expected to be rounded. So the water bottle and water bottle lid probably would be fine without it. Now, you may also be aiming to capture a sort of reflective surface (since those kinds of marks can create that impression), but generally for the purposes of our constructions in this course (especially in how we've been approaching it in the last couple years, which is driving our overhaul of the video/demo material which hasn't reached this far in), that's something we'd probably leave out of our constructions here.

I think the earbuds case construction would have been a good example where hatching to convey that curvature around its corners would make sense. As an additional note pertainig to the curves on the earbud case, I would also note that an additional step of cutting a few additional corners into your case before rounding them all out, would help due to how big of a curve you're going after. Here's an example of what I mean - instead of going from the box's corner straight to a curve, carve that corner into a chain of additional edges (in my example, 3 edges creating 2 corners where there was originally just 1) and then rounding each of those out.

Anyway! All in all, very solid work. I'll go ahead and mark this lesson as complete.