Todd, here are a couple...didn't take much in the way of progress photos of the drawing of the design. The one photo is a test cut of the scroll internals I did as I have not cut scroll quite like this before...close but not exactly.
It did take a number of hours over a few days to get the layout finished. I started with a proper sized pencil drawing, made an acetate transfer and then scribed the general layout onto the metal. There was much "erasing" (burnishing) and redrawing to get it all like I want it.
This takes a...
I DO NOT like surprises during an engraving project. Though some projects lend themselves to a bit of "design as you go", many, like this one do not.
This shows my drawing technique on bare metal. It is easily corrected along the way and easily burnished out when needed.
This one is now...
Welcome to the forum Onofre. I cannot answer your technical questions but expect someone will do so. It does sound like you understand the principles fairly well. I use the Lindsey Airgraver. I have built a few guitars and ukuleles just for fun and to experiment with engraved aluminum...