Funnily enough, I just finished a different Lesson 6 critique, and the student was also talking about how their ellipse guide (similar to you, a master ellipse template) didn't fit all the ellipses they needed to draw. So instead of rewriting the same explanation, I'll just paste what I told them below, as it applies equally to you:

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.

To add to that though, I guarantee you that as explained in the homework section for the 25 wheel challenge, while your wheels will inevitably be way smaller as a result of using the master ellipse template, that's still what you should be using. What you get from not having to worry about executing the ellipses just right, is far, far more valuable than what you might gain from drawing the wheels as a whole bigger. That's not usually the way that trade-off goes, and in this course we're usually very pro-draw-biiiiiig but in this case that's how things work out.

Alrighty! Jumping into your form intersections, overall I think you're doing very well in terms of what we expect from students at this stage. This exercise serves as an ongoing gauge of our spatial reasoning skills, and therefore of what this whole course is meant to develop - so when we introduce it in Lesson 2, it's to help provide context for the problem we'll be working on soon afterwards. When we assign it here, it's to see how things are going, and given that we expect students to be comfortable with intersections between flat sufaces, but still shaky with those involving curving surfaces, we find it to be a good opportunity to provide new information that they can leverage now, which they weren't necessarily in a position to leverage before.

In your case, I'd say you're further along than that, but you do still have some issues in deciding on which way to draw your curving intersections, based on the surfaces that are intersecting with one another, as I've marked out here on your work. I also noted a couple other points, including the notable absence of minor axis lines, which are useful for constructing cones and cylinders. and are included for those I draw in the demo for this exercise.

This diagram may be helpful - it shows how we think of our intersections in terms of the individual pairs that are intersecting (in the sense that though a box and a sphere may intersect, there may be multiple sub-intersections going on, with each one having to be solved separately before being stitched together). It also shows how a hard edge marks a sharp jump from one surface to another, and explores curved surfaces in that context, as the result of taking a hard edge and turning it into a more gradual transition from one surface to the other (and shows how this alters the intersection line). I think what will be most useful for you though is seeing how the orientation of the box's planes dictate which cross-section of the sphere to follow, which can help in ensuring your curves are flipped the right way.

Continuing onto your object constructions, overall you're making good headway, but I can see that there are cases where you take steps towards using the tools explained in the course to increase the precision of your results, but there are also cases where you opt to alter them in ways that reduces their effectiveness, and others where you decide where how far you're willing to take them has their limits. I'll address these with some examples in a moment.

First, some context. One of the things this particular lesson focuses on most is the idea of precision, and how we can control it, or otherwise control more about the outcome we're building towards. 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.

The thing about those orthographic plans is that they serve, as explained in this section from the lesson material, to allow us to make the decisions regarding what it is we're actually drawing ahead of time, so that when we actually construct the object in 3D space, we don't have to be performing two tasks (deciding and executing those decisions) simultaneously. We only have to worry about following the recipe we've already devised ahead of time. One might think that, "hey I've got a reference image, it contains all of my decisions" - but there's so much more involved, breaking down the structures, finding proportional landmarks, and as stressed in that section's example involving the placement of a handle on a drawer, making decisions where elements of the reference may be simplified as we deem necessary or beneficial.

I saw that you were generally making good use of this for the general structure of your objects in a number of your constructions - for example, this speaker and this flashlight, but that when it came to aspects of positioning the smaller elements (the buttons, mostly) that there were still points left for you to estimate/eyeball when tackling the 3D construction. So for example on the flashlight, each of the question marks I drew on there is a landmark that you'll have to estimate when doing the 3D construction, but ideally if we're pushing ourselves to apply each technique to its fullest extent (which we generally should be to get the most out of this course), you'd have made sure to identify them to some degree on the orthographic plan. It's not just about everything being pinned down fully - just taking steps towards increasing that precision. So for example, you don't necessarily have to pin it down with a very specific proportional measurement so you know exactly where it's gonna go - you could settle for estimating one of the 2 question marks I marked along the bottom (corresponding to the 2 vertical landmarks), and then use the mirroring technique to copy it across the center of the structure so your buttons are centered. Right now, we actually have no reason to believe that they are centered. This may not be as precise, since it still relies on estimation, but it's still significantly better and sometimes just making sure something is centered, rather than being placed very specifically, is enough for our purposes.

On the speaker, your addition of those two vertical lines enclosing either side of the buttons did increase precision (you didn't add it to the orthographic plan, but it still increased precision by creating a clear relationship between the left/right extremes to which each button would extend, keeping them all aligned) although where the precision was lacking was in ensuring that the thickness of each button's "bars" are more equal, and that they're spaced out equally - those elements were estimated instead.

This one was a very interesting case - I found it intriguing that you kind of worked with a triangular bounding box to start, but the more I thought about it, the more I realized while it works as a more vague, less precise manner of planning (and that has its place too), it was missing all of the precision-focused elements that a regular rectangular bounding box would provide - and so this is a case where I'd consider this entirely useful outside of this course, but not a case where you should have modified the orthographic plans from what is explained in the material.

The last point I wanted to call out is that you may have missed this section on handling curves. I say this both because you appear to have tried some approaches of your own to tackle this problem instead (like what we see here) and more importantly because of how you opted to tackle this mug's handle despite there being a demonstration in the section about curves that specifically handles this problem. So, be sure to go through the lesson material as thoroughly as you can, so as not to miss critical things. I admit, the later portion of the course are in a bit of a disarray, as there are elements we tweak and adjust to account for pain points students encounter until our overhaul of the video/demo material reaches this far into the course (currently we're working on Lesson 2 so we're a long ways off), but we do try and make stopgap changes to the written material to help account for those discrepancies where possible. That just means it's necessary to make sure you go through the written material carefully, so as not to miss them.

Overall, your work in this lesson is still pretty solid. You did make some choices not to apply everything to its fullest extent, but similarly to what I said about the purpose of the form intersections and the role they play in this course, this is where we introduce these concepts and techniques, and in Lesson 7 you will have ample opportunity to apply it as thoroughly and completely as possible.

As such, I'll go ahead and mark this lesson as complete.