So you’ve finally got a press, you’ve taken it apart, cleaned it, put it back together, and are finally printing on it. So what’s next?
Well when any surface moves against another surface, friction is generated which leads to heat, noise, and most importantly mechanical wear. Over time excessive wear can and most likely will damage the part and damage the machine. The lubrication helps to reduce the friction and thus reduce or eliminate wear. Just like you change the oil in your car regularly, you also need to oil your press.
What kind of oil do you use?
There are a lot of types of oil and even more opinion on what oil is best for you press. The type of oil that you use will depend heavily on your press and more specifically the amount of moving parts, the speed at which the parts move, and the types of surfaces that are in contact. For simplicity, the two presses we are going to consider are the Pilot and the C&P OS, although these guidelines apply to any similar machine.
A friend of mine once told me that the most important aspect when it comes to oil is to simply use enough. The grade of the oil is not as important as some think, after all any oil is better than no oil. Conventional motor oil contains additives specifically designed for internal combustion engines and none of which are really needed for a printing press. Simply put, the more additives a motor oil has, the less oil there is. Since you only need the oil for lubricating the moving parts, the cheapest kind of non-detergent oil can be used on your press.
Typical oils you will find in an automotive shop have three classifications:
We are primarily concerned with the viscosity grade but if you want more information I suggest starting with this article (HowStuffWorks: “What does the weight mean on a can of motor oil?”). The viscosity grade (for example: 20W-50) is a measure of the oils viscosity (thickness) as measured in centistokes and converted to grade using a SAE weight designation chart. Commonly, viscosity is measured in terms of the time it takes a standard amount of fluid at a specific temperature to flow through a standard orifice. A thin oil has a low viscosity grade and flows easily like water, while a thick oil has a high grade and is more resistant to flow like honey.
The viscosity grade on most modern (multi weight) oils is actually two numbers since the addition of polymers to the oil allows the viscosity to change depending on temperature. The first number in the grade indicates the weight of the oil when cold, while the second number indicates the viscosity at the higher temperature. The polymers resist the oils tendency to thin out at high temperature by uncoiling and stretching out (at cooler temperatures the polymers prefer to be coiled up and reduce viscosity). This additive allows the viscosity to be maintained at the same level over a greater temperature range.
So getting back to what oil is best to use on your press. Thinner oil is better suited to tighter clearances or for use on an old machine that hasn’t been oiled for a while and whose bearings are clogged. When you first set up a press it is best to run a thin oil through all of the oil spots until it runs clear. Once the bearings are clean, you can replace the oil with a heavier weight like 20W-50 that we use on both of our C&Ps. The easiest way to oil each one of the many holes is to use a pistol grip oiler, available at any local automotive or hardware store.
In some instances, grease may be more appropriate for lubrication since it will stick to parts that are exposed or hang upside down like the pinion and large gear cam wheel that are on the right side of your press. Grease is just oil with thickening agent added to vastly increase its viscosity. You can find grease at any automotive or hardware store.
Where do I oil?
This is pretty straightforward and luckily C&P provided an oil chart with the press. Below are the pages scanned from the manual which show you all of the important parts of the press to oil.
One last important tip I was told by an experienced printer and teacher was to label all of the oil spots on the press using a bright paint like yellow or red and to oil the press by starting at one side and working around until you get back to where you started. You should oil your press by topping off all oil holes before printing each time and replenish all oil for every 8 hours of machine use, though this might vary depending on the type of oil you use and your climate.