Jumping right in with your form intersections, from what I can see you appear to be demonstrating a solid grasp of how your forms intersect with one another, but there's one way in which you deviated from the example of the exercise that I would not recommend - both because it makes it a lot harder to assess whether your intersections are correct or not, and because it demands more of you as you work through it while providing little additional benefit: drawing "through" your intersections.

While this is undoubtedly similar to another thing we certainly encourage - drawing through our forms - that doesn't mean that this applies in every case, where the more you attempt to draw through things, the better off you are. It's always a trade-off. When drawing through forms, it makes the activity more complex, but it rewards us by adding a ton to our understanding of how those forms relate to one another in 3D space, rather than just how they exist as flat shapes on a page.

Drawing through our intersections however increases the complexity of the exercise considerably by giving us way more clutter on the page - which could be worth it, but from what I've seen from students it really doesn't accelerate their understanding of those spatial relationships. So, when doing this exercise, stick to just drawing the portion of the intersection that is visible to the viewer.

Now as I said, your work appears to demonstrate a strong grasp of those spatial relationships, but just in case I wanted to provide this diagram, which I generally share to students at this stage. At this point we actually only expect students to be comfortable with intersections involving flat surfaces, and while many do exceed that (as you appear to here), that diagram helps with pinning down one's understanding of how the intersections behave when curving surfaces are incorporated by reminding us to focus on the individual pairs of surfaces that are intersecting at any given point.

Moving onto your object constructions... I don't think there's really anything to be said other than wow. And maybe holy crap. While you're not the only one I've seen in the fullness of my ten years of critiquing drawabox homework to push things this far, you are probably among a few that could be counted off on one hand.

This lesson is all about precision, and the processes we can use to help increase it for a given construction. 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. And needless to say, you did that... and then some, and then some more. You pushed your orthographic plans to the extreme, and demonstrated an inordinate amount of care and patience in doing so. None of that is by any means a bad thing.

That said, whether or not it was strictly necessary is another story. Looking at orthographic plans like the one on this page shows a lot of awkward fractions, which suggests to me that you set out with the intention of nailing everything down as accurately as possible. In the section from the lesson notes on orthographic plans, I mention the following:

We are not finding the accurate locations for each landmark. Rather, we are deciding where they will go. The reference image is a source of information, but how we ultimately use it is up to us to decide, so we do have the freedom to say "I'm going to go with 2/5ths instead of 19/50ths". Of course the more of this we use, the further we may drift from the actual reference, but for our purposes in this course that is fine. What matters is that the plan we create here, and the construction we ultimately create in 3D space match up and follow the same process.

Always remember that your reference images are sources of information - they are not a plan of action handed down by on high. You get to choose what aspects of that reference are relevant to what you're constructing and what isn't, and by working in 3D space, constructionally as we do here, you have all of the tools you need to make modifications based on your own judgment. You decide what it is you're drawing, and to what specifications.

That is not at all to say that approaching it as you did is wrong in any measure - but making those decisions is a skill of its own, and one you'll want to get comfortable with. As far as the actual methodology you applied, I see no issues. You applied subdivision very effectively, and your constructions came out feeling solid and tangible. How you managed to keep everything straight in such a forest of construction however, is beyond me.

So! I'll go ahead and mark this lesson as complete. Keep up the great work, but... maybe take a break, as you have certainly earned it.

PS - I had a bit of a chuckle when I saw the comment "This was not a good object to start with to be honest" on this page, and made me think of something I'd written in the critique before this one, in response to the student thinking that they may have "cheated" by choosing overly simplistic objects in some cases. Here's what I told them, in case it provides you with additional insight:

Many students have the impression that they have to be working on complex objects, otherwise they're just cheating - but this is actually not the case at all, and there are lots of situations where students do themselves a disservice by actively trying to bite off more than they can chew. At the end of the day, the lesson isn't about creating an impressive body of work - it's about applying the concepts and working through the process of each exercise (the exercise in this case being constructional drawing).

Where a simple object may not be all that demanding, that means that you have more of your cognitive resources available to focus on the focus of the lesson and how it applies to those exercises. On the flipside, when we pick something that is intentionally over our head, we force ourselves to allocate more of those cognitive resources to dealing with that complexity, and therefore less is focused on the principles of the lesson.