Thank you JazzCNC for your words of encouragement! Very much appreciated!

I will certainly follow your advice and try to come up with a design to start the process... sounds like a good plan already! I will try and limit the daft questions to a minimum, but there are bound to be some ;-) ... in fact, I am going to start with one already: should I opt for a steel or aluminium frame? Aluminium would be lighter, but perhaps more expensive? Also, I can weld steel but not aluminium ... what would you suggest? This is a basic question for me, as it will steer my design in a specific initial direction. Thank you again!