Today it is easy to choose turning equipment that meets almost all requirements. Even desktop lathes perform many functions with amazing accuracy, and are easy to operate and maintain, so they are suitable for experienced turners and home craftsmen. Desktop equipment is small in size and low in noise; it can work both in small industries and in a personal workshop.
Scope of mini-lathes
Mini-lathes are called a reduced copy of industrial equipment. The definition is not very accurate, since the basic operations - the machining of small bodies of revolution inside and out - are performed, but many other functions of large modern CNC machines are not available to them. Yes, in general, and not necessary.
On mini-equipment, you can also cut external and internal threads, drill and bore holes, sharpen grooves, cut the ends of parts with sufficiently high accuracy and quality, the degree of which depends on the specific model of the machine.
It is not necessary to say that the dimensions of the parts and the various grooves and holes performed in them are comparable with the dimensions of the equipment.
The dimensions of the mini-turning equipment allow you to place it on a special small stand or on a table, so you can often find the name "desktop mini-lathe". For the stability of the equipment during turning operations, the machine is either placed in a special pallet, or its frame is rigidly attached to the stand.
Basically, mini-machines are not intended for industrial production, even single and small-scale. They are installed in home and school workshops, experimental workshops of research institutes and large enterprises, in auto repair shops and in small industries.
The device of desktop machines
If the machine is small, this does not mean at all that its design is extremely simple.
Mini Metal Lathe includes the main elements:
- the bed, which is the basis for all other parts and assemblies, is made of cast iron and has holes for fixedly fixing the machine on a table or workbench, as well as polished guides;
- the headstock, which houses the spindle, electric motor, drive, most often a belt drive, and a gearbox through which the rotation of the shafts is transmitted;
- the tailstock, which is used only when it is necessary to securely fasten a long part;
- Caliper designed to hold a removable processing tool and its precise movement. A processing tool is a cutter, reamer, countersink, tap or drill.
The tool holder on mini-machines is usually a single two-position. The incisors change when changing operations and are set in height. If the machine operates in small industries with full load, you can install a special adjustable tool holder on it.
Today on the market you can find mini-lathes even with numerical control, they are distinguished by increased accuracy and productivity.
The basic equipment includes a gearshift element, a drill chuck with a key, a tool holder key and a general purpose hex key.
The principle of work of desktop machines
Mini-lathes work on the same principle as large industrial equipment.
The principle of operation of the machine is simple.If it is necessary to process a sufficiently long part, it is fixed in the spindle chuck, a drill chuck with a drill is installed on the tailstock, and a center hole is made in the end of the part.
Then the cartridge is changed to a rotating center, which compresses the workpiece from the free end.
In the tool holder, the desired tool is fixed and set in height. The support is driven either by the feed handles or automatically, depending on the model of the machine and the selected processing mode.
The gearbox allows you to change the rotation speed and operating modes.
The part fixed in the chuck of the spindle rotates around a horizontal axis, and the cutter removes chips to a predetermined depth.
For processing metal parts, the cutter is made of carbide materials.
Main characteristics
The main characteristics of a desktop lathe are its weight, power and operating voltage. Weight in different models can vary from 10 to 100 kg. Power is almost always the same - 400 watts. Semi-professional models have a capacity of already 700 watts. The operating voltage can be either 380 V or 220 V.
The price of equipment is affected by its other characteristics. This is the height of the centers of the machine and the distance between them, the drive and speed of rotation, the support of the spindle and bed, chuck, design for mounting the tool holder.
Criteria for choosing a mini lathe
Today, the price of mini-lathes ranges from 20 thousand to 255 thousand rubles. To purchase high-quality equipment with a minimum of necessary functions, you will need about 40 thousand rubles.
In addition to its price, a few more parameters influence the choice of a machine.
First of all, these are operating conditions: its intensity and scale, the maximum dimensions of the workpieces (length and diameter of the turning), the quality of their material, the required accuracy and types of work.
The distance to the caliper (30-40 mm is sufficient for home use) and the distance between the front and rear headstock of the machine (300-350 mm) depend on the maximum dimensions of the parts.
The required accuracy makes us choose models of machines with a lower division price of the limb.
The power of the equipment depends on the quality of the materials.
The ability to connect equipment to a household electrical network is very important if you plan to use the machine at home or in a garage. In a small workshop, it is better to install a machine that operates on a three-phase voltage of 380 V.
The most optimal weight of the machine is about 45 kg. The quality of work does not depend on it, and a heavy structure can clutter up the space and create additional difficulties during transportation.
The speed of work and ultimately the loading of equipment and the timing of the execution of orders depend on the speed of rotation of the shaft with the spindle. The ability to control the speed allows you to process products from different materials on one machine.
The diameter of the headstock pinole affects the vibration of the part during processing, its value of 80 mm is considered optimal.
To reduce the time for intermediate operations, it is better to choose a machine model with a spindle reverse so that you do not have to shift the V-belt during reverse rotation of the part.
Even if at the time of purchase of the machine it is not intended to perform any additional operations, it is better to buy equipment with the possibility of understaffing with various devices.
Turning mini-machine "Corvette"
Domestic machine tool industry, focused on large industrial equipment, today can present desktop turning equipment of only two series - “Corvette” and “Handyman”.
One of the most common models is the Corvette 401 desktop lathe, the cost of which in the basic configuration is more than 53 thousand rubles.
It operates on a 220 V household electrical network, the rated motor power is 500 W, the mass is 38 kg, the noise level is 80 dB, the spindle speed can be 1100 and 2500 rpm. The maximum center-to-center distance is 300 mm, the processing diameter is 180 mm, and the chuck is 80 mm. The accuracy class for machining parts is H according to GOST 8-82, which establishes the general requirements for tests on the accuracy of metal cutting machines.
Only machine handles, keys, reverse cams, gears for threading are included in the basic equipment of the machine. A list of recommended devices is given in the instruction manual.
This manual also provides a complete specification of machine parts, a detailed diagram of its assembly and installation, as well as instructions for working on it.
Features of the selection of used equipment
For a small amount of work or infrequent use, it does not make sense to purchase expensive new equipment. The second-hand mini-lathe can cope with the tasks.
When purchasing used equipment, you need to adhere to some recommendations.
The machine must necessarily have supporting documents, a list of which is usually given in the instruction manual. Worn-out equipment often fails, and replacing a broken part or assembly can be a serious problem without specifying them.
It is impossible to determine the degree of wear during an external examination, but one can get some idea of it from work. The spindle must rotate evenly, without jerking, the accuracy of processing must comply with the passport data. If the machine works well and has all the necessary documents, then the purchase can be quite profitable.
For example, on one of the largest advertising platforms - the All-Russian site Avito - the Corvette 401 mini-lathe of the 2009 release, but with additional equipment costs 45 thousand rubles.
Desktop Combination Machines
If desktop compact machines become indispensable for a small-sized or mobile workshop, then what can we say about combined devices.
A mini-turning and milling machine, not only does not require a large area for installation, it costs less than two machines separately.
In place of the tool holder, the vise of the milling part is installed or the part installed in the centers is milled.
On a combined machine, turning, cutting, grooving, drilling, knurling, countersinking and milling operations are performed for cutting grooves and grooves, for producing profile surfaces, and for trimming.
For example, the Corvette-407 turning and milling machine combines the Corvette-403 turning and the Corvette-417 milling machine with all their technical characteristics and two motors: asynchronous power of 750 W for turning and collector power of 550 W for milling operations .
It is already considered semi-professional, although it works from a household network, the distance between the centers is 750 mm, the diameter of the turning chuck is 100 mm, and the workpiece is 220 mm, and the maximum mass of the workpiece is 60 kg.
Mini wood lathe
In woodworking, the division of equipment into industrial and domestic is much more arbitrary than in metalworking. On small desktop lathes, the vast majority of cylindrical parts are processed, even in large furniture manufacturing enterprises.
Almost the same machines are installed in home workshops, only a little smaller in size and power. An example is the Corvette 70 mini wood lathe with a power of 250 W and a mass of 20 kg. It can handle wooden parts with a diameter of 200 mm and a length of more than 300 mm.
The device of lathes for metal and wood is almost the same with the same front and rear headstock on the bed, electric motor and belt drive.In woodworking, tools and accessories for various types of woodworking, including shaped processing and art carving, are much more diverse. Therefore, a larger set of cartridges and faceplates for installing them on the machine. There is even a special device in the form of a nozzle on the spindle with an eccentric and sliders for turning ovals.
DIY lathes
There are many options for how to make a mini-lathe with your own hands, depending on the tasks performed. True, still more often home-made plants are used for the lateral processing of wooden parts rather than metal ones.
You can make a lathe from an electric motor with a power of about 1 kW with a reduced speed.
A faceplate is installed on the engine axis, on the cones of which a wooden workpiece is mounted and securely fixed. The second end of the workpiece, as expected, needs to be fixed in the center. The center is a metal rod with a thread along its entire length, fixed in a sleeve, which, in turn, is pressed into the central hole of the ball bearing. The interference bearing is inserted into a cage welded to a metal corner holder.
The shaft and the central cone of the faceplate must be aligned, this must be carefully monitored when installing the machine. During the operation of such a device, you need to hold the cutter with your hands, resting it on special bars so that it does not come off, therefore a low-speed engine is needed.
You can make a lathe using a drill, upgrading it for metal processing. In this case, the processing tool must be held in hand or fastened to the base at a certain angle.
The advantages of small-sized machines
Mini-lathes, despite their relatively low productivity, have undoubted advantages. Firstly, they have low energy consumption, which means that they are economically more profitable with small amounts of work. Secondly, the low noise level and small dimensions allow the use of such equipment at home. They are easy to maintain and easy to operate. And last, they are distinguished by their affordable cost.
Benchtop machines are capable of replacing traditional turning equipment. They perform many tasks with high accuracy and quality. They can be a cost-effective technical solution for efficient machining of parts.
