I just bought an old, thick butcher block (~16”) that has loosened up over the years and I can’t determine how old it is. It does have ~5/8” through rods that have washers and hex nuts on them.
I feel like since it has hex nuts it probably isn’t much older than the 50s or so, but that’s just a gut feeling.
When did hex head nuts become common in furniture? Is this evidence of the age or is it just too hard to tell from that one data point? Aside from an obvious mark, what other clues might I look for?