So that's what happened to me yesterday. I've been trying to work on the under-stairs pantry. I already installed the electrical boxes and wired them up. Before I can enclose that area with drywall, I needed to do some repairs to the bottom stair. But before I can do that, I needed to tighten up the newel post. I ended up taking the newel post almost completely apart. As I took it apart, I realized that the post (which is hollow) was only attached to the railing and nowhere else. There were a bunch of nails that had worked themselves too loose to be useful and they needed to come out. But to remove them, I had to take the newel post off completely. But before I could take off the newel post completely, I needed to repair the split in the handrail. (Are you seeing how cleaning out the coupon drawer works?) So I lined the crack with Frog Tape (to protect the surface of the handrail from excess glue) and gently pried the split open a little bit while applying Gorilla glue. I clamped it with every clamp I could find and wiped off any glue squeeze-out.
I left the clamps on overnight but was still able to take off the newel post while the glue dried. So the post came off and I removed the nails. The post's paint was in pretty terrible condition, and I've always intended on refinishing it eventually. I figured it would probably be easier to strip the paint while it was off, especially on the back side that abuts the balusters. So I spent some quality time with a heat gun and got off all the chipping paint that I could. Then I sanded it lightly with a palm sander. I still haven't stripped the paint off the mouldings, but I wanted to get the post back on for safety reasons. That stripe of paint in the middle is apparently where some long-missing piece of moulding goes. It circles the entire newel, and there are pencil alignment marks too. I'll see if I can find something appropriate to put there later.
Before I could reattach the newel post, I had to repair the bottom step. It has a rounded end, and the nails holding the curved piece in place had worked themselves loose when I was investigating how to tighten the newel post. (All the how-to advice on the internet indicates that there is a bolt underneath that can get retightened - this is not true for old houses with hollow newels.) I wiggled off the stair tread and made the necessary repairs. Then I reattached the stair tread and finally I was able to put the newel post back on.
I cut a block to fit snugly inside the post. I then repositioned the newel post into its spot and screwed the block down to the stair tread. Then I nailed the block to the post from the outside and reattached the handrail using screws. The bottom of the post doesn't rest on the step - there is a gap that is covered by the plinth. This gap prevents it from being rock steady, but putting the plinth back on fixed that problem entirely. Now it's as solid as can be.
So that's the (long) story of how drywalling a pantry turned into