Correct T.G. I use a #10 Optivisor. I turn 81 next month so am most fortunate to still have steady hands and great eyesight.
Mark, learning is what it is all about. Makes us keep coming back for more. Onward and upward!
I assume you are trying to avoid scale formation? There are powders available to coat the parts to stop that problem. I have been using Brownells PCB powder. You heat the part(s) to 500 degrees and emerse into the powder which forms a crust on the metal. After annealing and cooling you rinse...
The cotton/plastic cup with graverlube for most engraving and anti-seize lube (use what works for you) for aluminum is how I work. The plastic cup saves graver points.
Here are the two brands I have on hand,,,much the same product. I have found that with the lube, I have been able to produce engraving on aluminum just as detailed as on steel.
Might be spelled wrong but...Never-Seez is what I have used for many years. Found at hardware stores and auto parts. There are other brands that are likely as good.
When cutting aluminum you really need to use a good anti-seize lube to get good clean cuts. Aluminum galls very easily so sticks to the face of the tool and I wipe the tool frequently on some hard wood to keep it clean. Otherwise the tool will tend to wander.