CNC milling machine at home (garage)

Spindle device

Structurally, this important component of the technical device looks like this:

• a cutter is fixed to a metal shaft through an interference fit, a mandrel or a collet;
• to ensure that the cutting tool is firmly fixed, the end of the spindle is shaped like a cone;
• the device itself is located on a carriage to ensure movement along three coordinate axes;
• rotations are transmitted to the cutter, which ensures milling of the hole according to the specified parameters.

Important technical characteristics are power indicators and the number of revolutions of the cutting tool.

The operation of a CNC milling machine depends on power, namely:

1. For processing chipboard, MDF or plywood, a power of 800 W is sufficient.
2. If you need to process wood or non-ferrous metals with a milling cutter, then 1500 W is enough power.
3. Processing hard metal, stone or concrete requires a power rating of at least 3000 W.

It is easy to determine the operating mode of a single- or dual-spindle tool by the number of revolutions created. Engraving, cutting or milling modes are popular.

The choice of spindle must also take into account the reserve of rotation speed and power.

Components of the device

To make a homemade stationary wood milling machine with your own hands, you need to familiarize yourself with the main components of this mechanism. Self-manufacturing of such a processing device will help you save money, since the price of the finished product is relatively high.

Drive mechanism

At the design stage, the novice master must decide what power the engine will be used. If during operation it is not intended to carry out deep wood sampling, then you can get by with a motor with a power of no more than 500 W. However, in practice, such machines very often stall.

It is recommended to look at the drawings of a homemade wood milling machine.

The best option is to use a motor whose power ranges from 1-2 kW. If you have such a unit, you can use almost any type of cutter, processing wood in a standard mode.

Both an electric jigsaw for wood and hand tools, such as a drill or grinder, can be suitable for carrying out the work.

When choosing an engine, the number of revolutions produced per minute plays a significant role. The higher the indicator, the more uniform and cleaner the cut will be. It is best if the motor is designed for connection to a household network with a voltage of 220 volts.

Adjustment elevator

When making a homemade wood router, some attention should be paid to this device. An elevator usually consists of a body, sliding skids, a carriage, a threaded axle, and a screw for fixation.

When you turn on the device, the carriage should move up or down. The runners serve as protective stops. A locking screw allows you to secure the carriage in one position after selecting a specific height. As for the body, it completely holds the entire structure.

This is what a homemade spindle for a wood milling machine looks like.

Such a device provides regulation of the output of the replaceable nozzle directly above the table surface. For convenience, the elevator is equipped with special gears.

Support structure

If you don’t have a ready-made table, you can easily make one from wood. Although this material is afraid of moisture, it makes quite durable and reliable structures. During the work, various types of wood boards can be used to create the main plane.

Before the main work, drawings of a homemade wood milling table should be drawn up, on which the most important places should be highlighted. When planning, we must not forget about safety precautions. It is imperative to close the space around the rotating cutter.

You can make something like this table for a machine.

Manufacturing

In order to independently manufacture a device for a CNC milling machine for wood, it is necessary to take into account that the structure must withstand not only axial, but also lateral loads. Often, commutator motors are purchased for these purposes; they are cheap and operate at high speeds, but when switched to low speeds, they lose power parameters. To avoid such problems, a brushless motor is installed on homemade spindles.

As a basis, it is proposed to take a cheap milling machine with numerical control.

To design a spindle device you will need:

• electric motor (you can use the NTM brand, series 50-50, 5800 rpm and 2 kW);
• cone-shaped shaft;
• controller for electric motor;
• 2 bearings;
• collet clamp;
• a device for determining performance, including calculating speed characteristics during rotation, inclination angles, steps. This device is called a servo tester.

Making the nozzle

If necessary, a homemade wood cutter can be used to carry out simple work.

Detailed instructions for making such a nozzle are given below. The part will be made directly from the cutter blade in stages.

1. First, a hole is made exactly in the central part. For this, a drill made of hard alloys is used. Burrs and other defects are removed using a diamond file.
2. Next, the disk is centered. Using a simple pencil, the outline is clearly outlined. The outer edges are trimmed on a machine with a grinding wheel installed.
3. Next, the cloves are made using a cutting wheel. Their number is usually about 20 pieces. The angle of inclination of the slots should correspond to 30 degrees.
4. At the final stage, the prepared attachment is installed directly on the machine. For testing, you can use an unnecessary piece of wood. Wood sampling should occur evenly.

One of the stages of manufacturing a part is shown.

Attention! It is not recommended to heat-treat homemade wood cutters for a manual router or machine, as the quality of the cutting element can only deteriorate.

About the advantages of spindles

A homemade design involves the use of a machine with an inclined spindle.

List of advantages:

1. Equipping the machine with inexpensive clamping devices.
2. Manufacturing diagrams are easy to find on Internet resources.
3. Simplicity of the design solution.
4. Additional equipment with any elements of the corresponding parameters.

If you are not sure that a self-made metal spindle for CNC or wood will not work effectively, then to avoid the risk, you can purchase a factory-made product.

Initial information about the process

Before building homemade wood milling machines, it is recommended that you familiarize yourself with this processing method in more detail. The main element in this case is a special nozzle with a large number of teeth.

Depending on its type, one or another milling method can be performed:

• End machining is primarily aimed at making a groove or groove of a certain size in a part.
• Shaped technology involves working with profile elements such as baguettes, gears, and window frames.
• The end milling technique is generally applicable to the largest possible surfaces.

The end milling scheme is clearly demonstrated.

Addition! Quite often, specialized cutters are used that allow making a shaped cut. With this option, you can easily cut the material with additional processing of the edge part.

What to use for tabletop machines

If you need to outfit your desktop CNC machine with a suitable spindle, there are some pretty attractive options available now. It's up to you to choose the device.

1. Hand engravers. Such a device costs from 500 rubles. It doesn’t have any particularly strong qualities, but if you have to carry out repairs or milling of soft materials with small cutters, then this unit is quite suitable for equipping a machine with a vertical spindle. Disadvantages are low rotation speed and low power.
2. Drills. They operate very quietly and are equipped with a reliable chuck lock. At low engine speeds, the torque remains almost unchanged. This provides a significant superiority of the device over the engraver.
3. Spindle from DC motors. With a power of 0.4 kW they provide a torque of 12,000 rpm. It is convenient to carry out various repairs and milling work with such a spindle, since it provides weak runout and the unit operates quietly. Plus the collet is made to a widely used standard. But there are disadvantages - insignificant power indicators, strong heating, which forces you to look for effective cooling. To operate, the device will require a separate power source, for which it is also important to be prepared.

When choosing a spindle, focus on its quality and compliance with the machine on which you are going to use this element.

Types of devices

Spindles for a CNC milling machine and their features taken into account before choosing:

The choice of spindle depends on the material being processed and the number of workpieces to be processed.

Where are CNC machines used?

Such equipment is distinguished by its versatility in use, which has a positive effect on its demand and popularity in the market. Such devices can be used to work with the following materials:

• Tree.
• Plastic.
• Composites and polymers.
• Thin metal.
• Rubber.
• Other materials.

The most popular today are CNC machines, which are fully automated and provide maximum precision in wood processing. Using such woodworking machines you can perform the following work:

• Sawing a tree.
• Cut the plywood.
• Perform precision grinding.
• Perform complex three-dimensional and shaped wood cuts.
• Make various building materials from wood.

In each specific case, depending on the functionality of such a device, its design and the components used will differ. That is why you need to first decide on the functionality of such equipment and, depending on this, choose one or another type and design for the independent production of a CNC machine.

Equipment advantages

If we talk about the advantages of self-made CNC machines, we note the following:

• Efficiency at work.
• Versatility of use.
• Possibility of simplified reconfiguration of equipment.
• Reliability.
• Affordable price.

Assembly instructions

We offer you fairly simple instructions for assembling a CNC milling machine, which will allow you to independently create such equipment for wood processing. This scheme involves the use of ready-made sets of components, which include specially selected elements for the manufacture of such equipment. However, nothing prevents you from finding or making all the components yourself, and subsequently you will not only be able to save significantly, but also make a machine that will fully meet your requirements.

Preparatory work

• First of all, you need to decide on the scheme according to which the equipment you have made will subsequently operate. The easiest way to start is to use an old milling or drilling machine. In such equipment, the working head with an installed drill is replaced with a milling attachment.
• Next, you will need to make your own or use a ready-made mechanism from a kit that allows the milling tool to move in three planes. If you are assembling such a mechanism yourself, it can be made from carriages from an old non-working laser printer. Such carriages will allow the movement of the working tool in two planes.

Subsequently, it will be possible to easily connect a computer or control unit with software to the completed mechanism, which allows you to completely set the trajectory of the milling working head. At the same time, we note that if you use a carriage from an old filter, then you can only use such a CNC machine for processing wood, plastic or thin sheet metal.

If you need a CNC machine capable of performing full milling of workpieces from various materials, then a powerful stepper motor must be responsible for moving the working tool used. It can be done from a conventional electric motor or purchased ready-made low-power models.

The use of such motors will avoid the need to use a screw drive, which complicates the entire design. At the same time, the characteristics of such homemade equipment and its functionality are significantly expanded.

If for some reason you cannot or do not want to use a powerful stepper motor, then we recommend choosing carriages from printers of powerful top models, which will ensure the maximum possible amplitude of movement of the milling working head.

Scheme and drawings of the machine

The basis of a self-made CNC machine will be the milling mechanism. In the event that you use ready-made kits for performing such equipment, then you can select a mechanism that will fully correspond to the engine power and the subsequent work performed with wood and other materials.

On the Internet you can find numerous schemes for the implementation of such milling mechanisms for CNC machines.

In each case, the mechanism used will vary depending on the installed motors and carriages.

When choosing one or another design of such a milling machine, you need to give preference to equipment that combines simplicity of design and at the same time fully meets your requirements.

Assembling a CNC machine

First of all, it is necessary to construct the base of the equipment, to which the milling cutter, carriage and electric motor will subsequently be fixed. Such a base can be made from rectangular beams to which metal guides are welded or bolted.

The completed base for the machine must be rigid, which is necessary for accurate positioning of the milling head. Experts recommend connecting all metal elements of such a supporting structure using screws, which allows you not only to ensure the required strength, but also to easily upgrade your machines in the future.

The completed CNC machine must have a mechanism that allows the working tool to be moved in a vertical plane. We can recommend using a screw gear for such vertical movement of the tool, the rotation of which is transmitted using a toothed belt.

The vertical axis that every self-made CNC machine will require can be made from an aluminum plate. The dimensions of such a vertical axis should be exactly adjusted to the overall dimensions of the device you are assembling.

Having manufactured or purchased all the components for such equipment, you can begin assembling the machine. You need to mount two stepper motors that are attached to the base behind its vertical axis.

The first electric motor is responsible for moving the head in a horizontal plane , while the second ensures the movement of the cutter vertically.

The components and assemblies used are mounted, and due attention should be paid to the quality of their fixation.

During operation of such equipment, it is subject to increased load with vibration, and if the fastening is poor, problems with the accuracy of positioning of the heads may soon begin. The drive of all moving elements and working milling heads must be carried out exclusively using belt drives.

Selection of stepper motors

Most models of self-made CNC machines are equipped with stepper motors that allow you to move the working tool in three planes. Depending on the design, such equipment can be equipped with two or three stepper motors, and can also be additionally equipped with electric motors from computer printers.

When choosing the stepper motors to use, you need to pay attention to the number of control channels. The best models have five control channels, which increases the functionality of the manufactured mini-machine.

Also, when choosing specific models of such motors, you should familiarize yourself with their specifications and clarify by how many degrees the position of the head on the coordinate table changes in one step of the motor.

The positioning accuracy of the cutting tool will directly depend on this characteristic.

Electronic equipment

Today on sale you can find various ready-made microcircuits for controlling the operation of propulsion engines. It will also not be difficult to find appropriate software that will supply control signals to the motors, and, accordingly, they will lower and raise the working tool by changing their position.

An important point in choosing software is that it must support the drivers for the arduino controllers installed on your mini-machine. The control board is connected directly to a homemade CNC machine via the LPT or CNC port.