Bearings and Journal Boxes

Bearings

Railroads use two types of bearings for bogeys, plain or solid bearings and roller bearings. 

Plain bearings are made of babbitt and where in use for about 150 years. The bearing had to have a lubricant, mostly oil, witch had to be applied by "waste or lube-pad", if it did not get it you got a "hot box" witch can cause a derailment. A good working lube-pad did not show up until the 1950's witch was to late, laws banning them showed up.

     

Roller bearings have 30% less friction witch is why the first railroad car with them was made in 1830 on the B&O, they did not work out. More were tried in the 1920's but cost to make were to high. By 1957 only 10% of new cars came with roller bearings, by 1960 it was 64% and now is 100%. Roller bearings could be retro fitted to older bogeys by replacing the journal box or by modifying it.

You will never have to make bearings as they are inside the journal box but the journal boxes due look defendant, even the ones modified for roller bearings have a look.

Journal Boxes   

Plain bearing journal boxes have to have room for an oil supply, wast, a bearing, and the axle end all in a dust free box that can be opened a lot. So a journal box has a dust shield where the axle comes in and a spring loaded door cover.

I like to make this type as 3 parts, the round bottom part, the top part, and the door lid. The door lid can be dropped in LOD. the bottom part I make starting with a sphere and cutting off the top and back.

Roller bearing journal boxes can be "open" or "closed", the older ones are of the "closed" kind and come in a variety of shapes.

The "open" kind is what you see today and the center is part of the axle and should be animated.