4-Wire Horizontal Plotter
Introduction: 4-Wire Horizontal Plotter
This instructable explains how to make a 4-wire plotter using the wheel-rims from a toy car, four stepping motors, a scrap of sheet aluminium, some pulleys, and an Arduino UNO R3.
Unlike 2-wire vertical plotters the drawing surface for this plotter is horizontal.
Construction is simple:
* the “base” requires a ruler, a few drills and a saw.
* the “gondola” requires an electric drill, a set of circle cutters, and a sharp knife.
Features include:
* an on-board interpreter that recognizes the g-code output from “Inkscape”.
* accurate ... approximately 1mm with nylon
* scaleable ... just increase the cable lengths
* easy to make
* low cost
The estimated cost of parts, excluding the power supply, is less than $100.
Images
* Photo 1 shows a close-up of the plotter
* The video shows the plotter in action
Step 1: Parts List
The following parts were obtained from https://www.aliexpress.com/
* 1 only Arduino UNO R3 + USB cable
* 1 only SG90 servo
* 4 only 12VDC Nema17 17HS3430 stepping motors
* 4 only NEMA 17 Motor L-mount stepping motor brackets with screws
* 4 only 2A per phase Big Easy Driver v1.2 A4988 stepper motor driver board
* 4 only 65mm RC Car wheels with tyres on 50mm drums (see photo 1)
* 4 only hexagonal brass couplings with 5mm bore to fit the motor shafts and a 4mm hole for attaching the wheels. 16
The short ones in photo 1 are satisfactory.
* 4 only miniature V624ZZ pulleys with V-groove size 4*13*6mm
Optional:
* 1 only CPS-3205 Compact Mini Variable Adjustable DC Power Supply 0-32V 0-5A AC110-240V (not required if you already have a 12 volt 2 amp DC power source)
The following parts were obtained locally:
* 1 only sheet of 6mm composition board approx. 800mm x 600mm
* 1 only length 60mm x 20mm timber for corner supports
* 1 only reel of 0.5mm diameter nylon fishing line
* 1 only switch
* 1 only MBR735 diode for reverse voltage protection
* 1 only pkt of assorted Arduino jumper cables
* 1 only scrap of thin acrylic sheet for gondola annular ring
* 4 only M3 threaded Nylon spacers for supporting the acrylic annular ring
* 1 only scrap of thin sheet aluminium for pulley mounts
* 4 only M3 x 9mm tubular spacers for pulleys
* 12 only wood screws for assembling corner supports
* assorted M4 nuts and bolts to suit your particular build
* assorted M4 nuts and biolts to suit your particular build
The estimated cost of parts, excluding the power supply, is less than $100.
Step 2: Circuit Diagram
Photo 1 shows the circuit diagram of the 4-wire plotter.
The Big Easy Driver “direction” lines are on Arduino PORTC pins A0, A1, A2, and A3
The Big Easy Driver “step” lines are on Arduino PORTB pins D8, D9, D10, and D11
The SG90 servo “control” wire is connected to pin D3
The MBR735 diode provides reverse voltage protection.
Motor Wiring
It may be necessary to reverse the two center wires from each of the 17HS3430 Nema17 12 volt stepper motors as the Big Easy Driver v1.2 A4988 stepper motor driver boards expect the wires from each of the coil-windings to be adjacent.
The default color sequence for the 17HS3430 cables (for my motors) is red, blue, green, black. The color-sequence following the modification is red, green, blue, black.
The red, green winding is connected to the “A” terminals of the Big Easy Driver.
The blue, black winding is attached to the “B” terminals of the Big Easy Driver.
Big Easy Driver Current Limits
The current-limit on each of the Big Easy Driver must be set to 400mA (milli-amperes) . 611