A grease gun (gluing gun) is a familiar tool in a workshop and garage used for basic lubrication of many parts of machines. The basic function of a grease gun is to apply grease to an oil fitting or nipple through an aperture. This is done with a crank arm, which holds the grease plunger in a forwards and backwards position. With the crank arm a small pump pushes the nozzle of the grease gun along a small passage in the fitting; this is called a ‘dipstick’ or ‘intake’. Once the intake is complete, the crank handle can be rotated 180 degrees to wipe off excess oil.
There are different types of grease guns available on the market today. Some use standard air pressure to propel the lubricant along the lines while others employ high pressure. It should be noted that in the case of high pressure applications, some of the fittings may become permanently damaged as a result of excessive air pressure. When selecting a grease gun, the user should ensure that the proper pressure output is selected based upon the application requirements. In the case of high pressure applications where quick lubrication is required, then the user should select a model with a high initial velocity. High velocity models will also generally have a shorter throw and will have higher overall efficiency than lower velocity models.
There are basically two types of operation that a grease gun makes use of; positive suction and negative suction. Positive suction is generally more commonly associated with push button type tools, whereas the negative suction type is more often seen with suction cups used in conjunction with a suction tube. Typically the application is made with a positive suction feed; such tools have a suction line that extends from the end of the barrel to the tip of the cup. A positive feed allows for a quick increase in the amount of fluid expelled, whilst a negative suction feed increases the amount of fluid expelled without an increase in the amount of gun energy being expended.
Depending on the type of application and the amount of pressure that is applied, the power or speed at which the fluid ejects from the barrel can change. Suction feed systems generally operate at slower rates, allowing more fluids to be ejected per barrel rotation. Positive suction feeding systems can offer a faster rate of movement, although this may require an increased amount of effort to maintain a constant speed. If you need a greasing gun with a long throw, then a positive suction feed is usually your best option. Conversely if you need a fast system then a negative suction feed is the way to go. Each type has its benefits and drawbacks.
For general tasks, suction type grease guns tend to perform well. Their only drawback is that they tend to spit out a sticky, messy substance. The best approach is to aim at the bottom of a container and shoot the grease into it from above. They are also not very efficient when cleaning stubborn contaminates such as grease residue from an engine. On the plus side, they clean up nicely and don’t leave a mess.
Battery-powered grease guns are the preferred choice for most professional cooks. They are easy to use, clean and release no mess. You simply insert the batteries into the device and push a few buttons to start the motor. They are much more efficient than suction type devices as you can get more grease out per cycle. However, if you use the gun incorrectly it is possible to overheat the unit and damage the battery.
Trigger operated or hand-held grease gun models are available for both pistols and revolvers. They are very convenient as you can easily place them where you need them and there is little to no room to access the cylinder if you are using a self-contained unit. You have to make sure the trigger is in the “fire” mode before you use the device to avoid overheating. For those people who plan on carrying it on the belt generally prefer the trigger-operated models because of their small size.
The basic grease gun use is for light to medium-duty application. Most professional chefs and commercial food service workers prefer them because the cycle of operation is so simple and efficient. They are not only safer and easier to use than other types of units, but they produce a finer finish and they are often less expensive. Their simplicity and efficiency should be appreciated by those in the food service industry.