I'd like to see someone with some knowledge on the subject add a section to this entry explaining the physics behind how porcelain shards are able to silently break glass. Alvis 08:31, 19 February 2006 (UTC)
This issue is pending moderation.http://en.wikipedia.org/wiki/Wikipedia:Mediation_Cabal/Cases/_2006-07-30_Ninja_RocksAlvis 06:21, 30 July 2006 (UTC)
Anecdotal and OR but when I was a firefighter/paramedic and instructor at a college fire academy which also served as an area training center I found in a very limited experiment that throwing the metal part of sparkplugs to be more effective at breaking tempered windows than the shards which never worked for our one experiment on this rumor. I think I had three ceramic chunks cracked with a hand sledge against pavement which actually hit tempered windows 2 rear and one rear side window hits, we lost the other bits to misses, for no breaks and one break to a rear side window from a thrown metal plug bottom. These windows were later further abused and mostly left intact by firefighters hitting them with various pocket tools carried in their firefighter turnouts before demonstrating the effectiveness of a centerpunch. I pulled the plugs from a car we we were going to cut up for a class. On duty I carried a spring-loaded metal auto-centerpunch for making a drilling start dimple on metal, it had a hardened steel tip; a similar automatic centerpunch was also stored in the handle of the windshield saw tool carried on our rescue units, medic units, and engines. The spring-loaded centerpunch worked easily safely every time activated by hand pressure, while even whacking away a window with a brass or aluminum folding hose-spanner was hit or miss taking a few tries right at the edge and risking glass pebbles hitting occupants, and as I said the ceramic chunks never worked the one time I tried it, perhaps we didn't throw them fast enough. As for pushing on the 'ninja rock' micro pitted window story above, anyone who has cut glass will know that the pressure needs to come from the opposite side of the glass from where the scratch is made or it will not work, by this logic the 'ninja rocks' might pit a window but only an occupant of a locked car can push or knock and cause the window to shatter. Being OR my statements should have no bearing on the article but hopefully might lead someone in a position similar to my former instructor role to document and publish their results.79.177.28.128 (talk) 14:11, 7 September 2016 (UTC)
Hi, I’m the volunteer mediator who has agreed to look at this case. I have some initial reactions to things so far, so I will put those out to get the discussion started.
I spent a few minutes search but did not find any materials questioning ninja rocks online. Tsetna 15:07, 30 July 2006 (UTC)
I saw Ninja rocks on a television program once, they explained that it is because the glass has a negative or positive charge (can't remember which) and the ceramic has the opposite charge, so when forced together they react to each other and something has to give, which is the glass as its weaker than the ceramic.