Dec 292020
… but damn it’s cool. A Russian machinist first makes a bolt that can take nuts with either direction of twist:
And then makes a matching nut with both directions of twist at once, so you can thread in and out using whatever direction you want:
Tolerances seem pretty loose, so the nut wobbles a lot. But for a first attempt, it’s certainly far better than I could do. But what could you actually *do* with such a thing? Those “threads” would be far more fragile than normal, since they come to sharp little points rather than sturdier ridges. And the structure is doubtless much weaker than a normally threaded nut and bolt. Still… seems like their aught to be some application that these would be perfect for.