Quick POTD to hopefully fix an annoying problem in our house. I don't understand how and why it happens, but the shower knob in our upstairs bathroom gets continually broken during use. The ONLY person using it is our son. So, cheap plastic know or a gorilla in a man suit taking showers? The problem is the knob has a boss that slips onto the valve shaft which has two flats. I don't know if he's over-cranking the knob at the end of travel or not, but the boss blows out a side.
Idea was to sleeve the plastic boss with a piece of stainless. That way the outside of the boss is heavily reinforced and won't deflect/crack if it's over-turned on the valve stem. At least that's the theory . . . Measured the diameter of the new know at the top and bottom, measured the height and did the trig for the taper for draft on the boss.
Chucked up some 304 stainless and turned to diameter. Faced, center drilled, clearance hole drilled and bored the hole. Checked the diameter with the knob when I was getting close, then parted it off. Didn't show the operations, but filed a little chamfer on the knob end so it cleared the radius at the base of the boss.
Fingers crossed that the solution holds. Our son is away at college most of the time, so hopefully things hold up.
Bruce
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