cheap CNC step by step

Since a long time a want to build a CNC. It is something really useful.
The fact to imagine something on a computer and to see it becoming real is something I love :)
My aim is to build the parts too expensive to buy.
I would like to present a website I found: http://www.hobbycnc.hu/English.htm
There are nice examples of wood homemade constructions. 


1. The electronic


To start with the CNC I read  a lot of doc on how to do it.
What struck me is the fact that many people don't care about the price it costs and it is rare when they explain in details how to do.


My choice is to have 3 axis and a working area of 40*30cm. That is a good dimension to start :) I inspired myself with this website: http://id-conception.fr/


First of all I choose my electronic on Ebay (You can also go to aliexpress.com) a TB6560 3 axis CNC card.
There are two versions. The first one is blue, the other one is red. I recommend you to buy the red one. Because there is a conception problem in the blue one and the optocouplers are really annoying. They limit the speed and are not well connected. Moreover the don't isolate anything.

When you choose one be sure that it can deliver enough current!!!

I bought a blue one and removed the optocouplers:

Some  wires are straight because some opto were not well connected. So I used my modification to correct this.

 For the power source I choose an old computer power supply. I use the 12V wire (yellow for me, ground is black, 5V is red). We can found them easily, it is cheap and really powerful but it lacks on protections. It could be a good idea to put a fuse between the power supply and your electronic card.

2. The CNC construction
A. X axis

I choose to do it in wood and the MDF (medium) (Thickness : 15mm) this is not a natural wood but has a good behaviour when drilled and screwed. For the dimensions I start with a working surface near 45x30cm. It is enough for now.


Here is the base:

Then when I did this, I had to screw my slides.Since I don't want to spent too much money, brought this:

You can find this at a DIY store for a low price (near 7€ each peer for me). When I tested then I found them a little bit hard to slide so I used a screwdriver to push it aside:

If you look at my base's pic you see lines. I did them with a set square from only one side. So even if my base is not perfect, my rails will be well aligned. Then I screwed them but not too much tightened in order to correct some bad alignment:

Then you screw your working area:

Be sure it slides well and then screw it well.




A. Z axis


I know it can appear strange but I prefer to do the Z axis before the Y one. As I don't know its thickness, I will be able to adjust the Y axis.


I don't really know if what I am doing is the best way but let's try it :)


To start, here are the parts:

There are the rail, on medium part, mine is 10cmx15cm, some wood to elevate the medium and to create a space bewtween it and the bottom. I will not explain how to mount the rails since it is exactly the same way to do it.


When mounted:

 In the space I use a screw nut that can be hammered so it is easy to mount and the rod goes perfectly in it. I am still searching a good way to support the weight of the Z axis. I don't want the motor to support it. I have tried something but since I am really not sure it will be good, I don't show it for now.


A. Y axis


Now is the last axis part. The rails can be mounted direcly on the Z part like this:

Be sure there is exactly 90° with the Z rails. Measure the total thickness of all of this and subtract it to half of your X length.
For me : 25cm-12cm = 13cm


Now I know the length to cut the Y studs:

There is still something missing: the motors. I did a mistake when I choose them so I bought new ones on Ebay but I have to wait for them to be delivered :(