Gears are intended to drive all types of cylinders and
although they are a separate item, when they are positioned on the journal of a
cylinder it really becomes an integral component that is key to achieving a
quality printed result. As with anything else I am a great believer in you get
what you pay for so when ordering gears always buy from
a reputable supplier — usually your OEM or supplier that may have been
recommended by them.
All gears are
prone to wear over time due to the natural stress and pressure that is put on
them as they mesh together to drive various cylinders throughout any press. However if they are not maintained correctly then you
will see uneven wear patterns occurring, which can and will dramatically affect
your print quality. One of the major issues is ink that will inevitably get
onto your gears at some point and if not cleaned off in a timely manner will
attract further dust and other particulates, which if allowed to dry and compact
at the bottom of the teeth, will result in chatter and gear marking that will
show in your print.
You should
also look out for abrasive materials, in particular if you are cleaning your
rolls with baking soda or plastic pellets as they can and will also cause great
damage to gears and bearings if not removed as quickly as possible. Improper or
lack of greasing will cause dramatic wear patterns in all gears but you must
make sure that the lubricant is not itself contaminated as this can cause pitting
and other general wear to the teeth of the gears.
Running your gears dry will begin wearing the teeth of your gears immediately and should
therefore be avoided at all costs. To remove ink and other contaminants
from around the teeth of the gears, they will need to be scrubbed periodically
and re-lubricated. Gears that are noted to be showing any form of wear should
be replaced as quickly as possible. When gears cannot running freely and mesh
together consistently, it will result in horizontal banding across your print and
other inconsistent print results in both ink laydown and registration .
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