Unbending Furnace Zone Drain Valve Knobs

For reasons long lost in our house’s history, two of the zone drain valves on the furnace apparently had something heavy fall on them from a great height:

I was certain those knobs were made of brittle pot metal and would snap when I tried to un-bend them.

My weight bench being next to the furnace, I had plenty of opportunities to contemplate conjuring a 3D printed knob similar to the dumbbell nuts, but with the undamaged central part of the metal knob engaging the valve stem to avoid thermoplastic shapes around hot metal.

One can, of course, buy replacement knobs, but where’s the fun in that?

Expecting to cut most of the knob away, I applied needle-nose pliers to the rim and, mirabile dictu, not only did it not immediately snap, I managed to un-bend it into a reasonable facsimile of its original shape.

It wasn’t just beginner’s luck, because I did it again:

Both of those knobs have obvious fractures and aren’t the prettiest things you’ll ever see, but they don’t get a lot of use. I can say, without fear of contradiction, they’re in fine shape.

However, I’m certain those valves will need new washers if I ever turn those knobs …