Torque or physics review
In mechanics, the measure of how "strong" the servo is - that is, with what mechanical loads it can cope - is torque. Without going into vector complexities, we can assume that in the case of a drive shaft, the so-called torque is the product of the arm length and the force exerted on the end of the arm by our drive (motor or servo). Therefore the unit used for stepper motors or DC motors (especially those with built-in gears) is the newton meter - denoted by the unit Nm. For servos, it is commonly accepted that torque is expressed in a slightly different unit, i.e. kg*cm (1 kg*cm = 0.0981 Nm) - in the case of RC models or small mechanisms, such a conversion turns out to be much more intuitive. In addition to determining the power of the drives themselves, you must also select the appropriate servo cranks that will be able to transmit the set forces without excessive overloads.
Choosing the right orator for your application
It is obvious that the longer the arm that transmits the drive, the higher the torque that will be required to perform the job. Therefore, the mechanical strength becomes particularly important for longer armatures. Metal servo arms are irreplaceable in this case, not only because of the lack of deformation (which may occur in longer plastic arms), but also due to solid execution of holes which are used for connecting to cables or other elements of the mechanism. The length of the arm and the number of arms are the main parameters of the loader - sometimes a single-arm loader is enough, but in other applications where you need to operate two cables moving in opposite directions, you will need double-arm loaders. Some orifice plates have a circular disc shape with several mounting holes. Such elements are especially suitable for servos with unlimited rotations (servos 360 degrees, i.e. designed for continuous operation).
Servo eartrings in Botland's offer
In our offer you will find a wide selection of aluminum orbs, compatible with standard type servos. The 25T mark, visible on the upper surfaces of the eartags, informs about the design of the servo drive shaft - it is a knurled shaft with 25 teeth and mounting hole diameter of 3 mm. We have both straight orbs of various lengths, with one or two arms, as well as round (circular) or even custom profiled orbs (e.g. Feetech FK-AP-10). We offer double-armed spanners in symmetrical (e.g. FK-AP-4) or asymmetrical (FK-AP-15) versions. In this category you will also find a range of metal holders, allowing you to build "gimbal" type mechanisms.