This is just a short intro as to how I went about building CNC plotter. most of this is built using old printer and scanner parts or parts that can be easily found at a hardware store.If I left anything out just leave a comment. I built this for my final year project in college and looking back i really should have documented a lot more.
All of the code is available on my GitHub (username: brsc2909) as well as well as the files for manufacturing the pcb. as well as a more detailed report which you can download. you could build this on breadboard or strip board but a PCB is prettier. I'd love to see somebody build on this and turn it into a fully fledged CNC or 3d printer.
Step 1: Building the Actual Machine (the Hard Hardware)
I'm not a mechanical engineer so if your slightly squeamish look away now... there are better ways to build a cnc machine and this is probably a shoddy attempt at best but with a BOM of under 50 euro and being made from parts and scrap its not actually that bad.
the main frame:
this is made out of 1" steel box section, I created a jig with screws on a piece of plywood to hold everything in place while welding and it actually worked pretty well. I made the frame in two "H" sections first and then joined them together.
Step 2: X-axis
the x axis runs on drawer sliders and consists of a crude "H" section made out of 1x1 1/2 " timber. a 10mm layer of mdf creates a bed or base to draw on .i later added another layer of mdf with a hardened Formica top and used a bolt at each corner to level the bed. the pulley system was taken from a office laser printer that I mcGuyver'd together
the thread on all the axis's is M8*1.25mm so one revolution of the stepper motor moves the axis 1.25mm. couple this with 200 steps per revolution gives us 1.25/200 = 0.00625mm per step.
Step 3: The Z-axis
the most annoying part of the build for me anyways. as this was a "build with what i can get my hands on" type build it took quit a lot of reworking and re-do's to get this right. basically its a square in the middle that runs up and down the frame on roller blade bearing. a M8 nut fitted to middle on either side and two threaded bars connected to a stepper motor at the top of the machine provides the movement. the y-axis is also housed in this unit. in the end it proved to be steady and worked quit well.
Step 4: Y-axis
the pictures here can describe more than i can. i used rep-reap style timing belt to couple the motors with the threaded bar as well as rep-rap style pulleys.
Step 5: Intel Galileo Cnc Shield Controller
it would take me a week to explain every detail of this so i will include the schematic here. I made a pcb but you don't have to.
note: this will also work with an arduino but there are already better more complete arduino solutions out there.
Step 6: Galileo Cnc Windows Application + Controller Software
like the controller board i wont go through each detail but by all means if you have a question leave a comment. the
windows application is written in c and the the controller software is written in a mixture of arduino and c. you can get the code on my GitHub galileo-cnc . I would also advise you to have a look at the project report for more details. hope i have educated at least some of you and hope so see somebody repeat this and hopefully make it better.
Participated in the
Arduino All The Things! Contest
Participated in the
Full Spectrum Laser Contest 2016