In case that awkward title doesn’t paint a perfect mental picture for you, here’s a little more context: When we bought our split-level house, we didn’t really think much about baby proofing it. Now that the little guy is mobile, it feels like we spend about 98% of our waking hours making sure he doesn’t go tumbling down the stairs. We had a baby gate that could conceivably keep him out of harms way, but there was no obvious way to mount it at the top of the stairs. The solution I came up with was to design some 3D-printed clamps that attached to the existing metal railing and provided mounted points for a wooden frame. Thus, the “Semi-permanent Railing Extension” was born.