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Tuesday 31 October 2017 at 05:01
Quoted from vid1900:Get a ruler out and measure those rings.
Is it just that one set has more thread, or it is actually longer?
Here's a pic of the broken ring that came out of WCS94.It measures 2-1/2 inches from the top of the ferrule to the start of the threads.
Add 1/8" for the ferrule height to ...
Source: http://pinside.com/pinball/forum/topic/vids-guide-to-rebuilding-pop-bumpers/page/10#post-4048644