It is also possible to use any other available materials: ogglass, aluminum, plywood or chipboard. All parts of the base are fastened with screws (for additional reliability, glue can additionally be applied).

Supports and guides

As the guides used steel, polished (better still and harden) bars with a diameter of 12mm and a length of 200mm (on the Z axis of 90mm), two pieces per axle. Supports X, Y, Z move along the guides. The supports are made of a textolite 25x100x45, in which there are three through holes, two for the guides and one for the nut. The guides are fastened with screws M6 to the end. On the supports X and Y on the upper part there are 4 threaded holes for fixing the table and the Z-axis assembly.

Support Z

The Z-axis guides are attached to the support X through the transition steel plate (45x100x4).

Fastening of engines and lead screws

Stepper motors are mounted on brackets made of sheet steel with a thickness of 2..3 mm. The screw is connected to the rotor of the stepper motor by means of a rubber coupling (a piece of rubber hose). The use of a rigid shaft-screw connection led to wedging due to inaccuracy in the manufacture of parts.
The nut is made of bronze, pressed and pasted into the caliper.

Assembly
Assemble the CNC machine in the following sequence:

1) We install the guides in the slide and screw the guides to the sidewalls. Sidewalls on the base are not yet installed. Moving the slide on the guides we achieve a smooth stroke. We tighten bolts on sidewalls (we fix directing)
2) Guide assembly + support + sidewall with self-tapping screws to the base.
3) We collect the node Z. And together with the transition plate we attach to the support X.
4) Install the lead screws with couplings
5) connect the rotor of the stepper motor and screw the coupling and use the bracket to install the stepping motors. When assembling, we control the smoothness of rotation of the lead screws.

Recommendations

- Nuts of greater length will be more sensitive to inaccuracies in the manufacture of screws and assembly of the machine, which will lead to jamming. From the course "Machine parts" it is known that only the first 5 turns work in the screw-nut pair. In our case, there will be enough 10 thread steps. those. When using threaded screws with M6x1 threads, the nut length will be 10 mm.
- for the manufacture of nuts instead of bronze, cast iron can also be used. Other materials such as textolite, fluoroplast I do not advise.
- bought screws in the building store (studs 1m long) and cut into the required size. The accuracy is acceptable.

Works performed using a homemade CNC machine

Electronics (controller)

The electrician can be divided into three parts:

• Power Supply.
• Stepper Motor Controller
• Stepper motor driver

Power Supply:
12v 3A - to power stepper motors from the drive (5.25 ") and 5v 0.3A to power the controller chips. If you use stepper motors from the printer, then the power supply must be more powerful. The calculation is simple: 3 motors x two power windings in each x current of one winding (permissible 1A) then = 3x2x1 = 6A.

Controller:
The stepper motor controller is assembled on the 555TM7 series (3pcs). Does not require firmware. Schematic diagram of the controller:

The description and the purpose of the outputs of the LPT port connector. (table)

Vyv.	Name	Direction	Description
1	STROBE	Input and output	The PC is installed after each data transfer is completed
2..9	DO-D7	conclusion	conclusion
10	ASA	Input	Is set to "0" by an external device after receiving a byte
eleven	BUSY	Input	The device indicates that it is busy by setting this line to "1"
12	Paper out	Input	For printers
13	Select	Input	The device shows that it is ready, by installing on this line "1"
14	Autofeed
15	Error	Input	Indicates an error
16	Initialize	Input and Output
17th	Select In	Input and Output
18..25	Ground	GND	Common wire