Electronics

From ShapeOko
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There are a number of components necessary to move the axes of a machine.

Arduino microcontroller gShield Stepper drivers Power supply Stepper motors
E4.JPG Grbl shield.jpg E3.JPG E2.JPG E1.JPG
processor / control board mounts the stepper drivers which control the motors provide appropriate power / signals to the motors (these are integrated into the gShield) provides 24v of DC power, transforming it from whatever AC power your locale uses converts electrical current into mechanical motion


Microcontroller

A CNC machine needs to be able to take instructions to move to specific coordinates, and convert them into moment-by-moment, movement-by-movement signals for the Stepper Motors by sending electronic signals through the Stepper Drivers.

The typical choice for the ShapeOko is an Arduino, an inexpensive microcontroller board which provides a very good price for the needed precision.

E4.JPG

Stepper Shield

In addition to the microcontroller, the machine needs a system to take in the voltage necessary to move the motors and send it to the Stepper Motors.

Since, the gShield (formerly known as GrblShield) has become the standard choice --- this change was made to reduce the cost of the system and match its specifications with the machine's capabilities.

gShield (Arduino Shield for GRBL from Synthetos.com)

Please see the Advanced Electronics page for details on [Advanced_Electronics#Alternative_Stepper_Drivers|Alternative Stepper Drivers].

Stepper Drivers

It is necessary to take the signals from the Microcontroller and use it to apply the voltages from the power supply to the Stepper Motors --- the Stepper Drivers accomplish this. They may be soldered directly to the Stepper Shield, or installed into sockets, enabling replacement in the event of one being blown.

Power Supply

Any power supply that can produce 4.2A - 6A at 18-30v.

Note: We have successfully used 18V and 24v power supplies between 4A and 6A. Other power supplies may work. If you are unsure about anything related to powering the machine: STOP AND FIND A QUALIFIED PERSON TO ASSIST YOU!

I used an old power cord and connected the Load, Neutral, and Ground to the black, white, and green wires.

The COM connection on the power supply should be connected to the - on the driver shield. The +V connects to the + on the driver shield.

Power supply and arduino.JPG

Stepper Motors

The ShapeOko requires at least three stepper motors, one for each axis (Dual-drive Y-Axis is a popular upgrade and is now standard on the ShapeOko 2). The 58 oz-in motors listed are sufficient to drive the Shapeoko, but larger motors can be used. Forum Discussion. See Stepper Motors for more detail.

E1.JPG

Ventilation and Cooling

Two 12 volts DC fans in series can be connected directly to the power supply to cool everything as each one will have a voltage drop of around 12 volts. There has been some discussion in the Forums indicating this should not be done. Please research and consider the electrical aspects before doing this.

Further Alternatives

See also Advanced Electronics