When tightening down cap nuts on your playfield plastics, be sure to only
get them 'finger-tight'. They will not fall off if only 'finger-tight'.
This helps preserve your plastics, ensuring that they have a little give if
struck by the ball. This also preserves the playfield by ensuring that the
next time you remove the cap nuts the post screw doesn't come out of the
playfield, perhaps stripping the wood. It also speeds the next time you do
a ring replacement.