This mini plotter is made from 2 stepper motors which came from two DVD drives. I did this project to get better insight into the Stepper motor control which will help me in creating a 3D CNC Router in future. The plotter consists of 3 rectangular boxes made from 6mm plywood. The plywood boxes fit one inside other and slide on a 3mm steel rod. I have polished the steel rods so that the cradle can slide easily.
For drawing i am using a 0.2mm microtip pen. Lead screws on the stepper motors are very small so printing size is limited to about 1.5" X 1.5".
I was not able to make perfect bushing for the sliding mechanism due to this there is fair amount of play resulting in not so accurate printing.
To control the stepper motors and the servo from Arduino i am using Adafruit motor shield clone which is based on two L293D chip. This shield can power 2 stepper motors or 4 dc motors and 2 servos. This shield needs external power supply to power the motors properly.I was not able to make perfect bushing for the sliding mechanism due to this there is fair amount of play resulting in not so accurate printing.
The servo i am using is a 9g micro servo. It is a bit slow for this application. I wanted to keep the design clean and simple so i have used this servo otherwise I could have created the z-axis from another stepper motor which would have resulted in a quicker movement.
I have extended this sketch to include arc (G02 and G03) commands and also done some changes in configuration as per the stepper and the servo specifications. The two stepper motors that i am using have different lead screw pitch size so i had to do lot of experiment with the settings to tune them. I have uploaded the modified code on OneDrive (Download Code).
To convert an image into G-Code i am using Inkscape which is a free to software. You have to convert the raster image into a vector image first using Inkscape. After this we can use Inkscape G-Code generator extension to generate the G-Code. The G-Code settings have to be configured as per the printer specifications. This G-Code file will be used by the Hydra-MMM application to send the commands to the Arduino.
To convert an image into G-Code i am using Inkscape which is a free to software. You have to convert the raster image into a vector image first using Inkscape. After this we can use Inkscape G-Code generator extension to generate the G-Code. The G-Code settings have to be configured as per the printer specifications. This G-Code file will be used by the Hydra-MMM application to send the commands to the Arduino.
