[ToyCollector]

I have tried both the lead hammer and the "special wrench". Lead hammer wins hands down. The lead hammer will deform long before the spinner will, provided the spinner is of good strong material.

I actually use both sight and sound, mostly sound to tighten mine. When you use the hammer to tighten, you will hear a metallic ringing when to hit the spinner. Eventually it becomes a thud around the time it stops wanted to move in any significant fashion. I used to run around without safety wire--but at the time ignorance was bliss. Check the wire every now and again. I actually check my friend's wires when I see them as a favor and remember to do it.