November 18, 2011
We have noticed that many of the teeth on our press gears have various wear patterns on them. Can you describe the cause for the variety of wear patterns and what they may cause in our final printed result?
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 .No Comments