Damn between you, the guy making masks and the guy making books we could hold a full on art exhibit. I didn't realize how many people here have unique creative hobbies.
What got you into bookbinding? And why old books in particular? Do you do leather bound books too?
Everyone here is autistic. Spill the beans.
I'm a pure blood bibliophile, in short. Loved literature since forever, always read the classics. Got into antiquarian books as a collector building my own library, then as a part-time dealer/sourcer of rare texts for others. Eventually realised I was into binding as an art form, and had no shortage of texts in my collection I could work on.
Never tried leather, as that's some real speciality handiwork. I'd need actual training from experts to do it justice, though I do have decent experience using cloth. Had I been born 100 years ago, it's definitely something I'd possibly take up as a profession.
Edit: just realised you asked why old books. Newer books are made to cost more than ever, and even expensive volumes are printed to no greater quality than shitty airport hardbacks. Art books in particular can be beyond all reasonable cost, which is chiefly explained by their limited run, target audience, and likely return on investment.
Specifically, it's oftentimes difficult to get a hold of an antique copy in good condition. Sometimes even finding one that isn't in horrendous state is damn near impossibly, mainly due to age, on top of that exclusivity, rarity, even the size of a book can impact handling, etc. When you do find a book you've been after, there may be a disbound copy floating around for 20% of market value. I'd buy those copies which your average trophy collector wouldn't, fix them up, and turn them into sturdy reading copies. I'd then either keep them in my collection for reading or reference, or sell them on if I knew an interested party/it was especially sought after.
Example:
