[MadMax]

Heh ah heh..

Actually, technically busings are also bearings in engineering terminology. The term bearing is actually not very specific. When the word is applied to a part, all it asserts is that the part supports a load of some sort. A buttress on a church is a load bearing member. The washer on a stock spring guide is called a thrust bearing.

There is a bushing type in your AEG motor in the end bell (end where the brushes are kept) called a spherical bearing (or more specifically a spherical bushing). It can align itself with the front bearing because it's allowed to rotate in directions perpindicular to the shaft and reduce binding. The outside of the bushing is spherically shaped so it can align coaxially with the front bushing despite misalignments in the endbell. A cylindrical bushing press fit into the end bell would staunchly try to stay coaxial with it's seat so it could bind with the front bearing if it was also cylindrical. In the real world, you never have perfect alignment when you chuck things together. Good designs are tolerant to reasonable errors. In good motors, both bushings are spherical so they can both self align and become coaxial with the shaft and each other.

A ball bearing is a rotary bearing which uses rolling spherical elements to provide low rotational friction support to an axle.

So in engspeak, a bearing is the generic term. A bushing indicates a bearing which offers radial sliding surface support or even only alignment (you can use bushings to hold an inner barrel concentric to an outer barrel even though the inner barrel is not intended to spin). A ball bearing indicates rolling spherical element support. A needle bearing indicates cylindrical element support for very high radial loads as the inner and outer races ride on cylinders instead of balls.

If only airsoft would ditch +ive and -ive threading. It's supposed to be right or left handed threads which is meaningfull in machining or even physics terminology. A right handed thread rotates clockwise to tighten. If your curled fingers on your right hand point towards the direction of rotation, your thumb points towards the direction of axial travel. A left handed thread indicates a similar principle.

If current passes through a coil in the direction of curled right fingers, the thumb indicates a northward polarity of magnetism. I have no clue where +ive and -ive comes from.