Starting with your form intersections, you're demonstrating by and large a pretty solid grasp of how these different forms relate to one another in 3D space. I can see a lot of clear demonstrations of understanding of how to handle flat-on-flat intersections, as well as a lot of successful flat-on-round and round-on-round. There are some subtle corrections I'd offer, like adding a bit more to the intersection here - specifically having the upper left of the intersection line wrap along the more dominant curve of the cylinder's surface (the more we transition to moving in the direction of the cylinder's length, which is more straight). In effect, it's kind of like multiplication - if a surface is straight in the relevant direction of the intersection, then it can be thought of as representing a "1" (anything multipied by 1 remains the same, so if you have a straight surface intersecting with a curve, we simply follow the curving surface). Things get more complicated when we have two curving surfaces intersecting, resulting in more complex curves. Ultimately I do get the impression that you understand this fairly well, given that you've got plenty of those round-on-round surfaces handled properly, but I figured I'd call it out anyway. In addition to this, you can refer to this diagram and see if it touches on anything you might not fully grasp yet (though again - I'm seeing fairly clear signs that you do).

Continuing onto your object constructions, overall I think you have indeed done a great job when it comes to focusing on the core of this lesson - precision. 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.

Prior lessons didn't really deal with this much, in that we were approaching the constructions reactively, in a sort of inside-out fashion. So if the head of an animal was drawn too small, we'd continue building upon it, accepting that we're going to have a smaller head than our reference, but still being able to produce something solid and believable despite those inaccuracies. Here however, we hit the first lesson where we're working outside-in, starting with more defined bounding boxes.

To that end, you've made great use of those orthographic plans to make decisions ahead of time, and thus increasing the precision of your construction once you approached it. There are also lots of places where you leveraged techniques like mirroring and subdivision as you built up the 3D object itself, that didn't have quite the benefit of having made decisions in your orthographic plan, but still separated where the decision was made from the step where the mark was actually placed on the page, which still greatly benefits that precision.

Looking at those orthographic plans, I can see that you leveraged them differently across different constructions, which is useful because it allows me to discuss where your choices were preferable, and where they may have been more lacking. The one from this construction you've done great as far as the individual keycaps are concerned (allowing their tapering towards the top to be established in a somewhat more consistent fashion), and you were able to create a consistent grid in order to make them more evenly sized across the set, but in the orthographic plan there's no consideration to keeping the margins along the outer edges consistent to one another. You handled this better when approaching the construction itself (by defining the diagonals and using them to establish a more even spacing along the outside), but this was missing from the plan.

Additionally, while you did determine the height of the keycaps and the body relative to one another (0.54 for the keycaps for instance - though I may be misinterpreting that number since the keycaps do not appear to be more than half the height of the structure), writing numbers for it isn't actually particularly useful. What we want to do is establish the actual subdivisions for defining the proportional relationships between the different sections, using techniques that can be applied in 3D. That means that each of these do need to be established using the various subdivision and mirroring techniques from the lesson notes.

That said, the goal is precision - not accuracy. Let's say the keycaps occupied 11/50ths of the height of the overall keypad, leaving the body with the other 39/50ths, if we're looking at everything as accurately as possible. That would be a huge pain to subdivide properly. If however we set them as 1/5th and 4/5ths respectively, the loss of accuracy is minimal, and the construction becomes vastly easier to construct. This isn't always going to be possible - if you've got a landmark at 39/50ths, another at 40/50ths and another at 41/50ths, then due to the spacing you would need to get much more granular (since rounding them all to 4/5ths would result in them all being mushed together), but here that wouldn't be a concern.

Moving onto this kettle, here we're seeing things being done a lot more thoroughly. For example, if we look at the buttons - for the sake of clarity let's label them A, B, C, D, E, F from left to right, with A and F being the ones that are set further back than B, C, D, and E - then B and E are tightly enclosed within specific subdivided squares. This is due to each of those squares' 4 edges being specifically defined, so we know exactly how to plot out that same footprint in our 3D structure. For C and D, however, we've got 3 out of 4 edges defined tightly, with one left a little more loose. And finally, for A and F, we've got two edges tightly defined. In terms of how this plays out on the construction, it means that B and E are not going to be approximated or eyeballed at all - there's plenty of information to place them very specifically. But going from C and D, and then to A and F, we're dealing with a lot more approximation, and a lot less precision.

Now, all that said, you're still doing great. This lesson introduces these concepts, and you're pushing them pretty far already. Just remember that when you hit the end of the course, Lesson 7 will demand even more from you - so be ready to push the precision there as far as you reasonably can.

I'll go ahead and mark this lesson as complete, so keep up the good work.