These sketches weren't drawn for anyone else, they were a personal 'external hard drive' bound in a cardboard cover- the black book that pre-dates the black box. They were a part of my own visual journey to learn some new skills. They are rough and quick, but in giving emphasis to them with wobbly drawn frames and accented edges they became memories in themselves and the process of doing this reinforced little discoveries and helped me figure out priorities.
My visual diary or journal from learning to make instruments is pretty similar to the books I kept through art school and beyond. I think one of the reasons they became important to me was that learning something new or making a difficult thing really excited me, so the doing could be re-lived in the drawing, and this had the advantage of reinforcing creative experiences and helping me remember stuff- giving me reminders to come back to. Of course sometimes the drawings happen before the doing, and this enables visual testing of several solutions to little problems before taking up the tools. 'Several solutions' implies lateral thinking and that is a wonderful problem solving skill to adopt. There is always a multitude of ways to do anything and the art is in finding the most elegant and the most fit for purpose.
Ideas in the head get out more easily if they can be tested through drawing. Making bad drawings is cheaper than making bad objects and failure at some level is what creation is all about. Over and over, we can always do better by simply doing more -thoughtfully.
This sort of drawing is not about pretty pictures, it is visual communication of a more technical and maybe personal kind. I'm so grateful for the training I had all those years ago in life drawing and technical drawing- the opportunity to spend repeated sessions over four years just connecting my mind with my hands through exploratory lines. These things became a habit and a joy.
I suppose something similar happens now to the penless generations with CAD and all the Apps, but I'm suspicious that something very direct between hand and eye will be lost if hands can no longer draw communicative or exploratory lines (or even ordinary ones) that make some sort of sense. But I guess that only applies to the small group of people who make things...