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Sunday 8 April 2018 at 02:28
People with machines that have dimples say it's normal. People with machines that don't have dimples say it's not.
I almost saw a dimple on my original Williams playfields and I almost saw one on one of my CPR's.
Source: http://pinside.com/pinball/forum/topic/steve-ritchie-discusses-pinball-playfield-dimpling/page/2#post-4326641