1. as → axle (physical, supports rotation)
A rod or pin that supports a rotating body and about which that body turns. Its function is to carry and locate — it bears load and holds the rotating part in position. It may itself be stationary or rotate with the part; what it does not do is drive anything.
In BRANTS: the central member (10) inside the fabric tube (9), captured in the holder (15) and locked at the motor support.
2. as → shaft (physical, transmits torque)
A rotating rod that transmits torque or rotary motion from a driver to a driven part. Its function is power transmission. A shaft by definition turns; if it can't turn, it isn't a shaft.
In BRANTS: not used. Reserve for source terms where a driving function is explicit — aandrijfas, motoras, wikkelas, nokkenas, krukas.
3. as → axis (geometric, not physical)
An imaginary line: a line of rotation, a line of symmetry, or a reference direction. It has no material existence — it cannot be manufactured, gripped, or locked.
In BRANTS: longitudinale as → longitudinal axis; aslijn → axis / axial line.
The one-question test for the translator
Can you hold it in your hand?
No → axis.
Yes, and it drives something → shaft.
Yes, and something rotates on or around it → axle.
The fundamental difference is their primary function: a shaft transmits rotational power or torque (e.g., from an engine to a gearbox), while an axle supports the weight of a vehicle or machinery and locates the wheels, usually acting as the final mechanical link that drives them.