Page:Practical Treatise on Milling and Milling Machines.djvu/47

Rh Only good mechanics who thoroughly understand the construction of the different parts should be permitted to take apart and reassemble a machine, owing to the liability of parts being put together wrongly and alignments imperfectly made, if the work is intrusted to less responsible persons.

Arbors and collars should be kept clean and care exercised that chips do not get into the hole in the spindle or between collars.

Neatness about a machine is usually the mark of a good workman. By assigning definite places to tools and attachments and returning them immediately after using, he is able to know just where to look for any one whenever he wants it. The time required to replace tools in this way is more than offset by the advantage of being able to readily find them again; besides, the tidiness of a machine materially adds to the appearance of a shop.

It is well to remember when applying oil that ordinary bearings can hold only a few drops at a time and that this amount applied at regular and frequent intervals is far more beneficial than a flood of lubricant at irregular periods. It is a good practice to have one man attend to the oiling daily in shops where the machines are used by different workmen.

Kind of Oil. There are so many good machinery oils upon the market that it is hard to specify any one as the best to use for lubricating a milling machine. Any good coal or mineral oil can be used. Never use an animal oil, as it will gum up the bearing surfaces, oil channels and tubes, and have a tendency to retard rather than render easy the movements of the different parts. It might also be said that in buying machinery oil it is always safest to purchase a lubricant of reliable quality instead of experimenting with the less expensive brands. It is cheaper to buy good oil than to run the risk of damage to bearings from overheating or scoring.

Care of Driving Chain on Motor Driven Machines. The care of the driving chain on motor driven machines is important. It should be kept clean, well lubricated and adjusted. To clean a driving chain, remove it and immerse in a bath of kerosene or gasolene. This will loosen up the gum and dirt, and by working the joints while in the bath, foreign matter will come out. Remove the kerosene or gasoline by soaking the chain in a very hot and fairly strong solution of soda and water. Wipe dry and immerse in a bath of warm and quite thick lubricating oil for several hours. This treatment should be applied about every two or three months.