I had an old Steger & Sons piano from the early 1900s that was completely out of commission. I took the four main 4X4 posts out of it years ago to build a prototype platform bed, and I was left with a lot of other pieces laying around. Though that part of the piano served me well, I wanted to see if I could use more of the pieces, and help others recycle their old pianos as well.
So, in addition to some pieces becoming art on the wall, I decided to make a shelf that would restate what a work of art an old piano can be. I decided to make a piano key shelf.
Step 1: Destroy the piano and find your pieces
You'll spend considerable time taking the piano apart. If you'll plan for a day's worth of work, you won't be disappointed. Also, be prepared to handle a lot of slotted screws - no phillips-head screws in those antique pieces! You'll need to have various pliers handy to take out various screwed-in hooks, pins, etc.
WARNING: There are lots of pieces under tension in a piano! Things can snap very easily, even if you're just trying to remove a stubborn screw. Eye protection is highly recommended! I also recommend some steel- or fiberglass-toed work shoes, in case something falls apart before you gave it permission.
Once you strip the piano down to its pieces you'll want to focus on three main sets: one side of the piano (as in left or right), the keys, and the keyboard cover. If you don't have all the keys, no worries! I didn't either. I used wedges to fill in the gaps.
Go ahead and sort the keys into an order that works. The keys I had were numbered, but sometimes that didn't help. The keys were stamped around 1913 (I think), so 38 and 83 looked really similar, for instance. We also ended up with three #19s out of the same piano. Go figure. In any event organize them to fit together in a way that looks good to you as a shelf.