Congrats on completing lesson 6! I'll do my best to give you useful feedback so that you can improve.

Starting with your form intersections your work here is very well done. You clearly understand that the intersections occur between the surfaces of the forms rather than the forms themselves. The only issue I can see is that your linework for boxes and straight lines in general tends to be wobbly and not confident. Remember to ghost and always draw from the shoulder and at a fast enough speed which causes the line to be straight / confident.

Continuing onto your object constructions, frankly you've done a great job through and through. This lesson is the first point at which we really focus on the concept of precision in our constructions. Up until this point, going through Lessons 3-5, we're primarily working in a reactive fashion. We'll put down masses, and where the next masses go depends on how large or small we ended up drawing the previous ones. There's no specific right and wrong, just directions in which we're moving which impact just how closely we matched the reference. You can think of it as a manner of constructing that works from inside out. Conversely, what we're doing here works outside in - everything is determined ahead of time, and as we build out the various aspects of our construction, we either do so correctly based on our intentions, or we miss the mark.

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. Which you have done so for every construction which is great to see. However we can take those even further to identify specific positions of things before drawing them.

Let's take a look at your radio, I've drawn how I would identify each specific point on top of the radio. I stopped before it got too cluttered but hopefully you can see how we can use subdivision on the O.plan to make decisions of where things will go before going in to to draw them on a 3D construction. By doing this we can decide how we are going to draw the whole object before drawing it which allows us to focus on thinking in 3D space as much as possible.

Note that I said "making decisions" - this is not about finding the "correct" proportion, but rather deciding which one you will be using. So if you had a drawer face with a handle on it, and that handle extended from the 19/50ths subdivision to the 31/50ths subdivision, that's... a lot to ask of a person. There's not a lot lost in rounding it to 2/5ths and 3/5ths, as long as that rounding doesn't accidentally eliminate some other important elements as a result.

A final note about the use of solid black, you seem to mimic the way uncomfortable used it in his speaker demo, however he used it there because speakers are usually boxy objects and so the solid black lines highlight the curve. The way you've used it is more akin to form shading which isn't used in this course. Also you should define curves as straight lines first before drawing the curve.

So! You're doing great and have demonstrated a lot of patience and care in your object constructions by slowly building them up 1 line up at a time which will serve you well when you get to lesson 7.