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Tuesday 19 December 2017 at 22:12
Quoted from zgusto:dark lines down the right hand lane that gets the ball on every opening shot and some other wear areas.
Is that a sign of dirty, pitted balls?
Source: http://pinside.com/pinball/forum/topic/cleaning-and-waxing-pinball-machines-vids-guide/page/24#post-4131807