Find the magnitude and direction of the load, which will carry the bearing. This is a crucial factor when selecting bearings for your vehicle, manufactured with his own hands. For small diameter shaft and small loads typically use ball bearings, and heavy loads roller, which have a higher hardness.
Evaluate the nature of the load on the node. If the operation of the Assembly mating parts is the weight of radial type, cylindrical roller bearings having no flanges. Also in this case widely used needle roller bearings.
If the mechanism is designed to absorb the axial load, stop the choice on the thrust bearings. The load in one direction are more receptive to ball bearings single type, and if the load is distributed alternately in two directions, it is recommended to choose the suitable size dual ball bearing design.
In that case, when the intended load on the shaft will be combined, pick up roller bearing, provided with tapered rollers. To replace the angular contact roller bearing type, bearing in mind that the contact angle of the surface should correspond to the amount of axial load. The axial load capacity of the vehicle increases with increasing contact angle.
If in separate units, no prevailing radial and axial loads, use ball thrust bearings with a contact at four points or roller bearings are of spherical design.
In case of occurrence of technological errors, for example, in the form of a mismatch of the axis of the shaft and housing, will provide the presence in the mechanism of spherical ball bearings type. Their design is most able to smooth the error at the nodes, performed with insufficient accuracy. Bearings of this type are mounted in a spherical hole in the body of the particular unit.