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How To Choose Stepper Motors For CNC Routers

Generally, you are going to need at last NEMA23 from 175oz/in upwards unless your machine is very small such as a CNC engraver. These are quite often used for making Printed Circuit Boards(PCB) and if you check the description they will say only for soft materials.

Choose the correct stepper size for your CNC router
The choice of a stepper motor that is not an appropriate size usually shows itself in several ways. When you undersize the size of the stepper motor, this results in unsatisfactory deceleration and acceleration, poor performance as well as excessive heat. Additionally, in extreme cases, the stepper motor will position improperly, lose pulses or stop working altogether when under high acceleration or deceleration, and heavy loading.

Overloading, on the other hand, causes the stepping motor to produce higher RFI/EMI as well as to run louder. Because of this, you may incur an extra cost for a driver and motor as well as more machine or panel space than is needed.

Furthermore, because this is an open-loop system, the matching of rotor-inertia to load-inertia is vital. This is especially regardless of whether an encoder is added, but the inertia mismatch can never exceed the magnitude order. Typically, a greater mismatch results in the stepper motor missing position, using excessive current, losing pulse, or in some cases stalling altogether

After going through this article, you now have an idea of what you need to consider to help you choose a stepper motor for your CNC router that is of an appropriate size. Consequently, you will get to benefit from an effectively working machine that meets all your needs.

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The Disadvantages and Advantages of PM Stepper Motor

The Permanent Magnet Stepper Motor has a stator construction similar to that of the single stack variable reluctance motor. The rotor consists of permanent magnet poles of high retentivity steel and is cylindrical in shape. The concentrating windings on diametrically opposite poles are connected in series to form a two phase winding on the stator.

A permanent magnet stepper motor is a compatible and highly efficient device that has numerous applications. Since the rotor is made of permanent magnets, it does not need any external excitation which makes it very useful in applications such as toys, small motors, etc. Because of its design aspects, the step-angle of each rotation can be easily designed, which makes it useful in delicate applications such as medical instruments and aeronautical structures. Due to its small size, it is highly mobile and easy to use. This article discusses an overview of the permanent magnet stepper motor.

Advantages and Disadvantages of PM Stepper Motor:

The advantages of a permanent magnet stepper motor are
It is compact and small in size, which makes it useful in many applications
Due to the absence of any external excitation, the losses are less
Due to the absence of any external excitation, the maintenance is less.
It can be connected to the external circuit, to control the speed of the motor
Sensors may be used to locate the rotor windings
Can be operated in a wide range of speed and torque.

The disadvantages of a permanent magnet stepper motor are:
Due to limitations in permanent magnet, it cannot be used for high power applications
Torque produced is limited
The life of a permanent magnet is limited.

The applications of a permanent magnet stepper motor are:
Aeronautical industry
Control industry
Mills and printing