Hi Dave,
I agree with you on the aspect of building up of materials and tools by building instead of buying ready made, since I am really just starting out, and don't have much in the way of stocks of metal, or do I have a lot of experience in machining.
I do have some experience, as I have owned my Warco Mini Lathe, and Clarke micro mill/drill for around 10 years, but I had them in my shed, which is also the shed for my gardening stuff and my motorbike stuff, so I needed a good 20 minutes of clearing out before I could even get at my lathe! I have recently moved those tools into my spare bedroom, so I am starting to do all those projects I have been dreaming of doing for the last 10 years, LOL
Currently I am making improvements and accessories for my mini Lathe, and have also made a start on BAT, an O gauge steam loco, and started making L C Mason's small lathe – just because it looks cool, I'm planning on making C J Thorne's Clockmaker's throw, as well. So with all those projects, I should start building up a decent stock of metals, and get some valuable experience too.
As regards the boring head, I need it for a specific job, making a modified cross slide for my mini lathe, but I'm sure it will get a lot of use once I have one. I am inclined towards making it, because the experience will be good, and at the end of the day, I'll be able to point to it and say, "I made that".
Cheers
Ricky