Dave and I moved to a new place a few weeks ago — a long and frustrating process in itself — and there’s still much to do. We were going to be in San Francisco much of Sunday, so I wanted to get as much done on Saturday as I could. One of the bigger tasks remaining is getting our many dozens of boxes of books up from the basement and onto the bookcases that are on the second floor.

I decided the first thing I was going to do on Saturday was get the last bookcase bolted to the wall. The problem was that there was a TV wall mount solidly bolted to the wall that the previous tenant had left behind, and I didn’t have the right tool to unbolt it. Not that it was going to be a big deal, but I figured I was going to need a socket wrench, and I didn’t own any, and a set of decent socket wrenches was probably going to cost me at least twenty, twenty-five bucks. Money is kind of tight, though, since we just spent a lot on moving expenses last month, and Dave pointed out that we’d gotten a gift card from Home Depot for Christmas. Also, though Home Depot was a bit of a bus ride away, it was likely to sell individual socket wrenches, not just sets, and we could combine the trip with some other errands in the same area. So Home Depot it would be.

Indeed, Home Depot turned out to have individual socket wrenches at just $2.50 each. I had measured the bolt and gotten 7/16″ — I figured it was unlikely to be a metric size — and as the wrenches were inexpensive I picked up not just the 7/16″ but also the next standard sizes above and below, 1/2″ and 3/8″, just to be safe.

Unfortunately, both the bus ride and the errands took quite a bit longer than expected, and it was late afternoon by the time we got back. Even after getting the bookcase mounted, there wouldn’t be much Saturday left for carrying boxes up and unpacking them onto shelves. So I was eager to get at it, and I took the wrenches upstairs and tried them on the bolt.

Tried the 7/16″ — too big. Damn. Well, it was a good thing I’d bought the extras, then.

Tried the 3/8″. Seemed for a moment that it was going to work, but it was just a bit too small to fit around the bolt.

What the —? This is impossible. There is no other standard size between 3/8″ and — and of course that’s when I finally realized that these must be metric bolts.

Argh. It was kind of late to get to Home Depot and back and still have any day left for unpacking. We decided we would hit Home Depot on the way into San Francisco on Sunday, and I resigned myself to just carrying some more boxes of books up two flights and stacking them next where the bookcase would go.

At least now I could pinpoint the size I needed. In between 3/8″ and 7/16″ are 10 mm and 11 mm. I wasn’t sure off the top of my head whether or not 11 mm was a standard size of metric bolt, but in any case the 3/8″ wrench was very close to the right size, and the 7/16″ wasn’t, so what I needed had to be 10 mm.

I returned all three socket wrenches and picked up a 10 mm wrench the next day on our way into San Francisco. We got home after 11 pm, and I went straight upstairs and tried the new wrench on the bolts. I had the television mount removed from the wall in under ten minutes. And then I had to get to bed, since I was getting up early for work the next morning. So much for getting any books unpacked. (We did have a good time in SF on Sunday afternoon, though. More about that later.)