Vacuum belt press. Description of vacuum presses for veneering MDF and facades Make a vacuum press for pvc film

The furniture industry today is developing at a very active pace, which is associated with an increase in the well-being of people and, accordingly, with an increase in demand for furniture that improves the quality of life and makes it more comfortable. This, as well as the fact that modern consumers have become more demanding not only on the quality of furniture manufacturing, but also on its decorative characteristics, has led to the fact that enterprises operating in this industry have begun to increasingly use innovative methods and high-tech technologies in their production. equipment, one of the types of which is a vacuum press.

The use of a vacuum machine and appropriate consumables makes it possible to endow furniture with completely unique decorative characteristics, which significantly increases the competitive advantages of an enterprise that uses this equipment in its production.

Operating principle

The main scope of vacuum presses is the furniture industry, where such equipment is used in the production of elements of cabinet and upholstered furniture - for pasting elements of furniture structures with PVC film and veneer, which perform mainly decorative functions. The tasks of the vacuum press in this case include the deposition of a film or veneer and ensuring their tight fit to the surface of the element of the furniture structure.

The principle by which a vacuum press for veneering and coating furniture blanks with PVC film works is quite simple. The heated film, which has become more plastic, under the influence of the vacuum created under its surface, tightly fits the furniture blank, exactly repeating its configuration.

The film applied using vacuum technology on the surface of a piece of furniture made of MDF or chipboard lasts a very long time and does not contain even the smallest air bubbles.

The process of pasting a furniture element with a PVC film using a vacuum press includes such technological operations as:

• laying furniture blanks on the equipment table;
• coating of blanks with a film and installation of a clamping frame;
• sealing of the vacuum chamber;
• heating the chamber and pumping air out of it;
• cooling of blanks already covered with a film;
• cutting the film along the contour of the blanks.

Design features

Vacuum press for furniture facades and other elements of its construction consists of the following elements:

1. a vacuum table, on the surface of which furniture blanks are laid (the surface of such a table must have high rigidity, therefore it is sheathed with sheet metal or thick tin);
2. a vacuum pump, the task of which is to pump out air from under the surface of the film for furniture blanks;
3. clamping frame, which is also made of durable metal (the function of such a frame, equipped with reliable clamping elements, is to ensure the tightness of the air cavity under the film that covers furniture blanks);
4. heating installation, which can be made on the basis of various types of working elements;
5. vacuum press lid, which can be hinged or rolling type.

Most of the models of vacuum presses are additionally equipped with one or more shafts installed on the front side of the equipment. Such rollers, which make the operation of a vacuum press more convenient and reduce the time of processing operations, are used to install rolls with a film used for coating.

Many modern models of vacuum presses for MDF and chipboard can operate in automatic mode, which is provided by the CNC systems installed on such equipment. Particularly relevant is the use of CNC vacuum presses for enterprises producing furniture in series, when such equipment has to be coated with a film or veneer of many parts of the same type. In such cases, CNC systems installed on such equipment can increase its productivity and, accordingly, reduce the cost of products.

Main varieties

To date, two types of vacuum type presses are produced:

1. equipment of the usual type (such presses are used in cases where it is necessary to exert the most gentle effect on the workpiece, and are capable of creating pressure, the value of which does not exceed 0.95 kg / cm 2);
2. high-pressure vacuum presses (equipment of this type is capable of providing pressure, the value of which reaches 8.5 kg / cm 2).

Equipment of the first type is used in cases where it is required to cover products of a simple configuration with PVC film or veneer. Vacuum presses capable of creating high pressure are used for veneering or PVC film coating of complex shapes. In addition, such equipment is often used as a vacuum molder, with the help of which bulk products of various configurations are made from sheet plastic.

The purpose of the membrane in the design of a vacuum press

Both types of devices are equipped with a special membrane, so their more correct name is membrane-vacuum presses. Such an element of a vacuum press is used both when veneering elements of furniture structures, and when they are covered with PVC film. In the first case, the membrane is necessary in order to increase the pressure exerted on the surface of the workpiece and the coating material during their connection. In addition, when creating a veneered layer on the surface of an MDF or chipboard blank, the membrane prevents the coating material from shifting relative to the surface of the blank during their joining. When covering furniture blanks with too thin PVC films, the membrane protects them from the negative effects of high temperatures created in the vacuum chamber.

The membranes that are equipped with vacuum presses can be of two types: rubber and silicone. Silicone membranes are the preferred option, as they are more wear-resistant and allow even very small parts to be coated with PVC film.

Other applications

In addition to pasting the surface of elements of furniture structures with veneer and PVC film, a membrane-vacuum press (MVP) can be successfully used to solve other problems, which, in particular, include:

• transfer to any surface of inscriptions and images by sublimation;
• formation of volumetric parts for various purposes from plastic sheets.

To transfer images from special paper to almost any (including embossed) surfaces by sublimation, equipment such as a thermal vacuum press is used. Using a thermal vacuum membrane press, it is possible to apply inscriptions and images on products made of ceramics, plastic, textiles and other materials.

The principle by which the membrane vacuum heat press works is as follows.

• The product with a sheet of paper attached to it, from which it is necessary to transfer the inscription or image, is placed on the table of a vacuum press.
• A tight pressing of a sheet of paper with an image or an inscription to the product is provided by the press membrane, under which a vacuum is created.
• Under the cover of the press, after closing it, a temperature is created, under the influence of which the image or inscription from the paper is transferred to the surface of the product.

Vacuum thermal presses, represented on the modern market by a wide variety of models, are actively used by both large printing enterprises and small companies engaged in the production of souvenirs.

For the manufacture of relief-shaped products from sheet plastic, a forming-vacuum press is used. Using such a molding machine, operating on the principle of a membrane-vacuum press, it is possible to produce three-dimensional products from flat plastic sheets, the depth of depressions or bulges on the surface of which reaches 500 mm. Cases of vacuum presses of this type, as a rule, are designed for sufficiently large products, which makes it possible to produce a wide range of products on such equipment.

Modern models of molding vacuum presses equipped with CNC systems have an option that allows you to simultaneously heat different parts of the workpiece to be processed to different temperatures. This makes it possible to manufacture bulk products with a rather complex relief from sheet plastic. The entire processing process on such equipment is controlled and controlled by the CNC system. Thus, do-it-yourself vacuum forming when using this equipment is not performed, the machine operator only sets the program, the machine does the rest.

How to choose the right equipment

When choosing a membrane-vacuum press for solving certain problems, one should focus on its most important parameters.

Brand and country of manufacture of the pump

Pumps from foreign (usually Italian) or domestic manufacturers can be installed on vacuum presses. In the first case, a membrane vacuum press will cost more, but the pump that is installed on it will be more reliable. Meanwhile, domestic vacuum pumps are also quite reliable, but most importantly, there should not be any problems with their repair, since it is not difficult to find spare parts for domestic pumping equipment.

Vacuum table lining material

It is very important that it be metal, and not chipboard sheets, which some manufacturers use for such purposes. After a short use, tables made of chipboard will simply become unusable.

Dimensions

This is one of the most important characteristics that you should pay special attention to when choosing a membrane vacuum press. The dimensions of the vacuum press primarily determine the number of workpieces that can be processed on it at the same time. Naturally, the larger this amount, the more productive the vacuum press will be. Meanwhile, it should be taken into account that the dimensions of the equipment directly affect its cost, so in this case the best option should be chosen.

Type of heating devices

The predominant majority of experts advise choosing vacuum presses equipped with KGT lamps, when using which the film glued to the top of the bent parts does not melt or burn through. In the same case, if equipment equipped with heating elements is selected, then it will be necessary to constantly monitor that the distance from such heating elements to the very top of the workpiece surface is at least 150 mm.

Press brand

Since vacuum presses are quite expensive equipment, it is not worth choosing a device from unknown manufacturers, which then has to be constantly repaired.

Self-made vacuum press

Many private furniture makers and owners of small furniture companies, guided by a natural desire to minimize costs, are wondering how to make a vacuum press with their own hands. You can make such a machine with your own hands, it is easy to find drawings of this equipment on the Internet, and there are no special problems with the purchase of components for it. An important incentive for the realization of such a desire is the fact that the cost of a home-made vacuum press, if you approach the issues of its manufacture correctly, will be significantly lower than the cost of serial equipment.

If you wish and have good skills in working with technology, you can also make a machine for vacuum molding with your own hands, if there is a need for equipment that allows you to make bulk products from flat plastic sheets.

Before you start making a vacuum press with your own hands, you should study the design of such equipment well, determine the technical parameters of the device that you need, and purchase consumables and accessories. In addition, you can use the advice and videos posted on the Internet of those who have already made a vacuum press with their own hands and share their experience.

Making a vacuum table is the most important stage in the design of a do-it-yourself thermal vacuum press. At the design stage, it is necessary to determine the dimensions of the table, choose the material for its manufacture, consider methods for fixing and sealing detachable elements to maintain internal negative pressure (vacuum). The vacuum table is made with the same basic set of tools as.

Further in the text, a vacuum bath will be called a part of the vacuum table - a steel container, inside which the lined workpieces are located, and from which air is pumped out. Under the working dimensions (dimensions) of the vacuum bath, we mean its useful volume, measured by internal dimensions. Let's agree to call the vacuum table the entire structure as a whole, consisting of a vacuum bath, an upper (movable) clamping frame, clamps and other, smaller elements.

External and working dimensions of the vacuum bath.

Consider the general principles for choosing the size of the vacuum bath, we will designate specific numbers for our press.

The longer the vacuum bath, the more workpieces can be placed in it, or a larger workpiece can be lined. On the other hand, the longer the bath, the more film has to be consumed in one working cycle, the larger the dimensions of the machine are, which entails a greater consumption of room space. We need to find the optimal size. As experience has shown, the optimal working length of the vacuum bath, intended for the manufacture of standard furniture facades and decorative door linings, can be considered a value from 2.4 to 2.6 m. We will make a vacuum bath 2500 mm long, the working length of which will be 2500 - 40 x 2 = 2420 mm (40 mm - the width of the short wall of the profile pipe).

The width of the tub is directly related to the width of the PVC film used. Depending on the manufacturer of the film, there may be different widths, the most common is 1.4 m, and we will focus on it. We choose the width of the bath equal to 1400 mm, the working width will be 1400 - 40 x 2 = 1320 mm. When facing high blanks, for example, for curved (radius) facades, the width of the bath must be reduced (make it smaller than the width of the film), but to work with such blanks, a press of a different design is needed, so these issues will not be considered.

The working height of the bathtub must be calculated taking into account the fact that there must be a small free space between the upper surface of the facades and the covering film. In other words, the film stretched over the blanks should not touch them before the air is pumped out. The calculation is the following. Firstly, the vacuum (breathable) table top, which will be the first to be placed on the vacuum table, will be made of 10 mm thick MDF board. Secondly, the linings for the facade blanks will be small pieces of MDF board 16 mm thick (this is the simplest, most common and optimal lining option). Thirdly, the thickness of the coated blanks will be from 8-10 mm (door linings) to 16-32 mm (facades and other furniture elements). Fourthly, the sealing rubber will add about 2 mm to the depth of the bath. As a result, the maximum height of the entire “pie” inside the bath will be: 10 + 16 + 32 = 58 mm. For the manufacture of a vacuum bath, we use a profile pipe with a cross section of 60x40 mm, placing it on the short side. At the same time, the height of the free space will be at least: 60 + 2 - 58 = 4 mm, which is quite enough.

Making a vacuum table.

Vacuum bath.

The bottom of the vacuum bath will be a sheet of steel 2 mm thick. To minimize sheet deflection under negative internal pressure, and to give the table surface an even shape (close to an ideal plane), it is necessary to make a stiffening frame. For the manufacture of the frame, we will use the same profile pipe 60x40x2. The pre-cut pipe, in accordance with the project, is laid on the slipway, rigidly fixed with clamps, and all joints are welded. After making the stiffening frame, a steel sheet is welded on top of it. This is the most critical stage of welding work, it requires tightness from a continuous weld (double penetration is recommended).

To avoid warping of the sheet under prolonged high temperatures, the following alternative method of welding the sheet to the stiffener can be used. Before laying the steel sheet on the stiffening frame, it is necessary to apply a sealing compound around its perimeter that can withstand high temperatures (for example, high-temperature silicone sealant), and welding should be carried out not with a continuous seam, but with small regular fixing tacks with a pitch of about 50 mm. This method is based on the fact that short-term, local impacts of welding cannot damage (burn out) the entire sealant, but only a small part of it in the immediate vicinity of the tacks, while most of the sealant after curing will perform its direct function.

Vacuum table dimensions.

Detailing the stiffening frame and the procedure for assembling the vacuum bath: the stiffening frame is welded, a steel sheet is welded to it, a stationary (lower) frame is hermetically welded along the perimeter of the steel sheet with a part of the swivel joint for attaching the lifting (upper) frame.

Photo of the vacuum table from below.
The stiffening frame is made partly from an angle profile.

Lifting (clamping,top)frame.

Frame material - profile pipe 60x40x2 mm. The dimensions of the pressure frame must be exactly the same as those of the vacuum bath. If it was not possible to find a sufficiently even (not bent, not twisted) profile, then it is necessary to select in advance in pairs several of the most even whips, from which parts of the vacuum table that are tightly adjacent to each other will be made.
The pressure frame will rise thanks to the adjustable swivel joints. The hinges are adjusted after gluing the sealant - strips of sheet rubber of medium hardness, about 2 mm thick.

Welded washers are needed to increase the friction area. The swivel pin is a D12 steel bar with threaded ends.

Gas lifts can be used to hold the pressure frame up. For safety reasons, it is recommended to install four gas lifts (two per side) and make sure that any three of them are able to hold the frame. If the opening angle of the frame (45°) turns out to be insufficient, the frame will cause significant inconvenience in work, it can be raised as far as possible up to an angle of slightly more than 90°, using the thermal module parked behind as a support (gas lifts are not used).

Clamps.

To securely and tightly hold the film during vacuum pressing, it is necessary to firmly and evenly press the upper frame to the perimeter of the vacuum bath, achieving a universal fit of the rubber seal. For these purposes, you can use various ready-made clamps, clamps, or you can make them yourself.
For the manufacture of home-made clamps that work on the principle of an eccentric, you will need the following steel rolled metal: half a meter of a DU50 pipe (outer diameter of about 60 mm), two meters of a rod with a diameter of 10 mm, and about the same amount of a profile pipe with a cross section of 20x20x2 mm.

Firstly, the DU50 pipe is cut into 8 equal 60 mm segments. Each section of the pipe is finished with a semicircular central cut, having a width of 10-11 mm and an arc length equal to 3/4 of the length of the outer circumference of the pipe. We will get 8 pieces of eccentric rotary cylinders, to which it is necessary to weld a handle 220 mm long from a square profile 20x20 mm.

Secondly, the steel bar is cut into 16 pieces: 8 pieces 190 mm long (for studs) and 8 pieces 55 mm long (for pivots). It is necessary to weld an M12 nut (or M10 with a drilled thread) to one end of the stud so that it can rotate freely on the pivot, and cut the M10x50 thread at the other end.

Thirdly, to complete the manufacture of the clamp, we weld the ends of the king pin (with a nut with a welded stud previously put on it) to the inner surface of the eccentric rotary cylinders.

To install the clamps on the vacuum table of the press, through holes with a diameter of 10 mm are drilled at eight points of the table, according to the project. After that, the upper holes are enlarged, giving them an oblong shape. Adjustment of the clamps is carried out by installing the combined nuts in the right place of the thread of the stud, followed by fixing with locknuts. This operation is performed at the last stage of manufacturing the vacuum table, after gluing the rubber seal.

Elements and dimensions of the swivel clamp.

Hooks for clamps are made of steel angle 50x50x3.

If it was not possible to achieve a flat surface of the table.

If during the welding process the sheet has undergone significant deformations that go beyond the permissible values, then pick up a grinder and cut off the welds, there is no need to redo everything again. It is possible to provide a perfectly flat plane of the vacuum table by additional measures, namely by using epoxy leveling compounds, which are used in the manufacture of poured floors. To do this, the vacuum table is set strictly according to the level, the required volume of bulk mass is determined (for example, using a test filling with water), the bottom of the vacuum bath is cleaned of rust, and primed. Fill with the prepared epoxy mixture according to the manufacturer's instructions. For reasons of economy, the mixture can be diluted with some cheap filler, such as quartz sand. To speed up the curing of the mixture after pouring, the table can be heated from above in a controlled manner with the heat from the thermal module. It makes sense to carry out this filling leveling operation after the vacuum press is fully ready, test samples of the product have been made, and a decision has been made on the need to improve the geometry of the working surface.

Estimated material for the vacuum table.

Name	Length, mm	Quantity, pcs.	Purpose
Profile 60x40	2500	6	Rigidity frame. Bath. lifting frame.
Profile 60x40	1380	4	Rigidity frame.
Profile 60x40	1320	4	Bath. lifting frame.
Profile 60x40	1001	6	Rigidity frame (diagonal).
Profile 60x40	753	3	Rigidity frame.
Profile 60x40	250	4	Hinge.
Profile 60x40	180	2	Hinge.
Profile 60x40	150	2	Clamp support.
Profile 60x40	140	2	Hinge.
Corner 50x50x3	50	8	Lifting frame (clamping hook).
Profile 20x20	220	8	Clamp.
Pipe DU50	60	8	Clamp.
Rod D10	190	8	Clamp.
Rod D10	55	8	Clamp.
Rod D12	150	2	Hinge.
Nut M10 combi		8	Clamp.
Nut M10		12	Clamp. Table fastening.
Nut M12		16	Clamp. Hinge.
Washer d12		12	Hinge.
Bolt M10x60		4	Table fastening.
Sheet 2500x1500x2		1	Table (bath bottom).
gas lift		2	lifting frame.

Upon completion of the main scope of work, the vacuum table is installed on the frame (on specially provided supports) and fixed at the corners with four bolts, as shown in the figure, after which they proceed to minor work: installing and adjusting the clamps, adjusting the lifting frame hinge, gluing the seal.

The metal structure is beginning to take shape of the future thermal vacuum press, but it still lacks many elements: a vacuum system, a thermal module, an electrical control unit, which will be discussed in the following articles.

Thermal vacuum forming is a batch molding of plastic sheets using negative pressure and high temperatures. PVC plastics, polystyrene, PTG, as well as ABS plastics are used as the starting material.

Specialized vacuum forming equipment is quite expensive, but you can easily make your own DIY vacuum forming machine.

How to make a homemade vacuum forming machine

To make a vacuum forming machine with your own hands, you will need the following:

Sheet plywood 15-20 mm or chipboard

wooden bars

Profiled pipe 20*20

Vacuum cleaner compressor

Heating element (for example, from the oven)

Iron legs from a chair

The design is very simple, we heat the plastic over the shade, and then transfer it to a vacuum table, where the compressor draws the heated plastic to the working surface. Plastic meets a model on its way, according to which it takes shape.

So, let's start manufacturing.

To begin with, a holder for the compressor is made, ordinary bars from the household store are used.

The walls of a homemade vacuum machine are assembled using the fittings at hand.

Holes are cut in the sides of the walls for air to escape from the compressor.

The working surface is drilled with holes in increments of 20 mm.

Before fixing the working surface, a sealant is laid on the walls. You can also use silicone sealant.

Frames for clamping plastic are also equipped with a seal. Its purpose is to reduce the amount of air leaking through the gaps in the structure.

To clamp a sheet of plastic, ordinary bolts and nuts are used. To facilitate the removal and installation of sheets, wing nuts can be used.

An old case from a VCR was used as the heater case, the inner surface is lined with a GVL sheet, asbestos sheet can also be used. The heater power is 1 kW, the power is excessive, so the heater does not have high side walls.

That's all. As you can see, making a homemade thermal vacuum forming machine is not at all difficult!

If everything is not clear from the photos, watch a video on the manufacture of a vacuum machine and its use. In this machine, the oven of a conventional electric stove is used as a heater. And as a vacuum engine - an ordinary vacuum cleaner.

As you can see - despite the simplicity of the design, it works quite well.

Leo32 comments:

It’s cool, but, as I understand it, is such a machine relevant for those who make batches of parts according to the same model?
For one-time production, it is suitable only if you need high quality and lightness of the product.
Otherwise, you can also make precipitation from a bottle.

Artem comments:

Great item for the RC model lover!
You can mold homemade bodies for RC cars!

A vacuum press is a unit that allows the production of furniture facades with PVC films and decorative door linings based on MDF. It can be purchased or made at home.

The material will be devoted to how to make a vacuum press with your own hands, and what is required for this.

Remember that such work is quite difficult, you need observe safety rules, because it is associated with the use of power tools of a high degree of danger and heavy structures. If you want to assemble a press with your own hands, evaluate your capabilities, and if it is difficult for you, it is better to entrust this matter to a professional.

Vacuum press: purpose and principle of operation

Film furniture facades are widely used in the manufacture of cabinet or upholstered furniture due to the following characteristics:

• a wide range of colors;
• variety of forms;
• affordable cost.

Such facades produced on special equipment, while the main production tool is a vacuum press. It shrinks a PVC film onto the surface of an MDF-based workpiece.

The press includes the following key elements:

• vacuum chamber or table;
• thermal module.

The chamber most often has a rectangular shape and is made on the basis of a rigid material that does not compress under artificially created negative pressure from the inside. And outside, a PVC film is laid, the edges of which are sealed with the frame.

film shrinking process includes the following steps:

• laying blanks on the table;
• sealing;
• film heating;
• air pumping;
• cooling;
• cutting blanks and removing excess film from the facade.

Do-it-yourself vacuum press: what you need to know?

Before working on the independent manufacture of a vacuum press remember the following:

If you plan the purchase of components and do the work correctly, the cost of a do-it-yourself press will be significantly lower than the factory counterpart, and you can make film facades and MDF lining at home.

Before you start making a bed for the press, you need to pick up optimal type of heating unit, since this will affect not only the design of the bed, but also other elements of the press. When assembling with your own hands, it is best to choose a retractable thermal module, which is easy to assemble and easy to use, but it has large dimensions.

For the manufacture of the bed you will need:

• steel profiled pipe;
• rails for thermomodule.

The bed design is best modeled on a computer using special 3D modeling programs.

Required to work the following set of tools:

• small one-handed angle grinder with a disc diameter of 115 or 125 mm;
• welding machine;
• electric drill;
• locksmith set, including a hammer, wrench, pencil, tape measure, etc.

Assembly steps the stands will be:

• cut the steel profile into parts according to the cutting charts;
• lay them out on a flat surface in accordance with the project, align and fix with clamps;
• tack the joints of the parts, taking into account the final welding on all sides or full welding of the seams without tacks;
• knock the slag off the seams and check their quality;
• if necessary, clean them with a grinder with a grinding wheel;
• drill holes;
• clean the surface with a metal brush from rust;
• prime the surface;
• paint it with a brush or spray can.

For operation, the welding machine can be selected based on AC transformer, inverter type device or semi-automatic device.

The table assembly stage is the most important when assembling a vacuum press with your own hands. At the design stage, decide on its size and material, on the basis of which it will be made, also consider how to fix and seal the connector elements in order to preserve the internal vacuum. Tools for work will require the same as for the bed.

vacuum table is a design that includes the following elements:

• bath;
• clamping frame;
• clamps and other items.

vacuum bath

You need to calculate the size of the bath before assembling it. Remember that the longer it is, the more blanks will fit in it, but at the same time you will use more films in one working cycle. As practice shows, its optimal length is about 2.5 meters.

The width of the structure depends on the width of the applied PVC film, most manufacturers produces products with a width of 1.4 m.

And the working height of the bath should be provided taking into account the presence of a small space between the upper part of the facade and the film with which it will be covered. So, before the air is pumped out, the film should not touch the workpiece.

A 2 mm thick steel sheet is suitable as a bottom for a bath, and a profile pipe is suitable for a frame. The pipe cut in advance must be laid on the slipway, fixed with clamps and boiled all the junctions. A steel sheet must be welded on top of the stiffening frame.

Manufacturing of clamping frame and clamps

We make the frame on the basis of a profile pipe, its dimensions must strictly correspond to the parameters of the bath. To keep the pressure frame up, you need to put 4 gas lifts and make sure they are able to hold it.

Clamps are needed in order to ensure a reliable and tight hold of the film during the pressing process. To do this, the upper frame must be firmly and evenly pressed against the perimeter of the bath. Clamps work on the principle of eccentrics, they can also be made by hand on the basis of rolled steel.

To install them, holes must be drilled at 8 points on the vacuum table. At the same time, the upper ones increase and give them an oblong shape. Further, they are adjusted by installing nuts in the threads of the stud and fixed with locknuts.

If the table does not have a perfectly flat surface, then you need to cut off the welds with a grinder, you do not need to do everything again. Also, to ensure evenness, you can treat the table with special epoxy compounds, setting it strictly according to the level and cleaning the bottom from rust.

Vacuum system installation

A vacuum system is needed to remove and pump out air so that the film can easily fit the surface of the workpieces.

When installing it , keep the following points in mind:

• it is desirable that the system components are not custom-made, and they could always be purchased at retail;
• it is best to choose inexpensive components with satisfactory reliability and ease of use;
• the system must provide the air pumping speed and vacuum depth, which are enough to create standard flat facades and overlays;
• the air removal system should not be demanding on the environment and food quality;
• controls and controls should be simple and inform about the current pressure, also with their help you need to smoothly adjust the speed of pumping out air.

Such a system consists of the following elements:

• water ring vacuum pump with water tank;
• pipeline for delivering air from the table to the pump with a valve and a pressure control device;
• tabletop for pumping air from any point of the table, regardless of the position of the blanks and the film.

Features of the water ring pump and its installation

The pump must have the following specifications:

• productivity 1.57 m3/min;
• three-phase motor voltage;
• electric motor power is 5.5 kW;
• residual pressure 0, 45 mm Hg;
• rotation speed is 1500 rpm.

His the working principle is as follows:

• the impeller rotates eccentrically in the cylinder in the direction of the arrow;
• there is a working cavity between the wheel hub, water rings and the body, it is divided into cells by the wheel blades;
• during pump operation, water is thrown from the sleeve to the housing under the influence of centrifugal force, and the volume of the cells increases and air is sucked in. Then this volume is reduced, and the gas is pushed out through the discharge window during compression;
• in order to maintain a constant volume of the ring and to remove heat, only clean water must pass through the pump. It is supplied to the central hole in the pump housing and discharged through a special device that separates water from gas. This prevents water from being drawn out of the discharge pipe along with the air.

The pump should be installed on a special foundation or in a concrete floor, it should be leveled, then it should be fixed with anchors through standard holes. Next to it you need to put a water tank with a volume at least 30 liters. Two tubes are attached to it, one takes water with a pump, and the second drains the waste liquid into the tank. During circulation, the water is heated, and this negatively affects the operation of the pump. To ensure its natural cooling, the tank must be made of a material that conducts heat well, in particular steel or aluminum.

The pipe supplying water to the pump must be equipped with a tap that can shut off the water when idle. The tank and pump are connected by flexible hoses and fastened with metal clamps.

When you have assembled the pipeline and fixed it to the press frame, installed and connected the pump, you can test the system. For this purpose, power the pump in a timed manner by means of a circuit breaker. But it is better to postpone testing until the moment when the electrician of the press is ready.

How to make a thermomodule with your own hands

The thermal module is a heating device that allows you to evenly heat the film to the required temperature and hold it for some time.

This stage of work is considered the easiest when assembling a vacuum press. For the frame of the thermal module, we need a steel pipe with a cross section of 20 by 20 mm. It will be necessary to weld the cases of profile wheel supports and L-shaped handles to the frame to move along the rails of the module. Wheels can be ball bearings.

Next, the frame is needed sheathed with sheet steel and secure with aluminum rivets. On the side of the casing, it is necessary to cut rectangular openings for viewing windows and insert silicate glasses there, having previously darkened them with a tinting film. Cut one 50mm round hole next to each window, this will be a reference window to measure the temperature of the film, and they must also be equipped with sliding shutters. And in order to improve the reflectivity, the thermal module must be equipped with aluminum foil from the inside.

To create a thermal module we will need:

• exhaust riveter;
• metal scissors;
• spanners;
• press tongs;
• insulation stripper.

Now you need to install the heating elements. Linear lamps KGT (quartz halogen thermal) are suitable for this. They have a number of advantages:

• affordable price;
• high resource;
• efficient transfer of thermal energy through radiation.

Connecting the lamps according to the wiring diagram is the final stage of assembling a vacuum press. The lamp connection scheme takes into account the requirements in terms of the symmetry of a three-phase load and the possible zonal control of groups of lamps depending on the level of distance from the center of the table.

Now you have an idea about the independent manufacture of a vacuum press. If you decide to take on this job, then do not forget to use personal protective equipment, since it is not only difficult, but also dangerous if safety rules are not followed.

Nowadays, you can see everywhere products that are made using vacuum forming technology. This approach allows you to quickly produce plastic utensils, packaging, mannequins, paving slabs and much more. To do vacuum forming at home, you need a special machine. Such devices are expensive, and they are too bulky. This article will look at an example of creating a simple vacuum forming machine that uses only a vacuum cleaner and an oven.

Of course, the power of such a machine will be small, so it will not work to make bulky items or simply make a large number of products in a short time. But for the sake of interest and small household needs, such a machine is quite enough. In addition, with the help of such a machine, you can perfectly make cases for various models, be it ships, planes or cars. You can also make elements for various homemade products. This device is a kind of peculiar analogue of the "3D printer".

Materials and tools for homemade:
- vacuum cleaner (the more powerful, the better);
- oven (needed to heat the plastic);
- wooden bars;
- drill;
- self-tapping screws;
- screwdriver or screwdriver;
- plywood or chipboard (thickness 16 mm);
- silicone (as a sealant);
- fiberboard for the work surface (plywood is also suitable);
- aluminum tape;
- wood, gypsum (or other materials for creating a mold).

Machine manufacturing process:

Step one. Vacuum machine dimensions
The main element of the vacuum machine can be considered a frame on which the plastic is heated, as well as a vacuum chamber. The dimensions of the frame must be such that it fits in the oven. You also need to take into account the dimensions of the plastic sheets from which future products will be created. The frame is made from wooden bars.

Step two. Making a vacuum chamber
The vacuum chamber is needed to "suction" the plastic, which, in turn, will envelop the form below it. To make a vacuum chamber, you will need a 16 mm chipboard sheet or plywood. Technically, a vacuum frame is a box, its dimensions must correspond to the dimensions of the frame that will fit on it.

First, a frame is made from timber, and then plywood is screwed to its bottom. Since the chamber must be airtight, all seams must be coated with sealant during assembly.

The vacuum chamber also has a working surface, that is, a place where products are formed. It is a sheet with evenly drilled holes. For these purposes, fiberboard is well suited, but plywood can also be used. It is important to understand that the work surface should not sag, so a spacer is installed in the center.

Step three. We connect the vacuum cleaner
To conveniently connect the vacuum cleaner to the vacuum chamber, the author used a nozzle from a vacuum cleaner. It must be screwed to the vacuum chamber, having previously made a hole in it to pump out air. The nozzle is attached with self-tapping screws, it must first also be lubricated with silicone or other sealant.
If there is any doubt about the tightness of the structure, it can be glued on top with aluminum tape or other adhesive tape.

Step four. Forms for homemade products. Product creation process
To create a form, you can use various materials, for example, gypsum, wood and others. If the forms do not have to be perfectly smooth, then polyurethane is ideal for these purposes, since it is easily processed with a clerical knife.

If there are concave places on the form, then holes must be drilled here so that the plastic can “suck” into these recesses. A drill with a diameter of 0.1 - 0.5 mm is suitable.

After the mold is made, you can proceed directly to the molding process. The work will be carried out in the kitchen, as access to the oven is needed.
First you need to connect the vacuum cleaner to the vacuum chamber and place the mold in the center of the work surface. From the bottom of the form, you need to put gaskets 1 mm thick, coins will do. This is done so that the plastic better fits the shape below.

Then, along the perimeter of the frame, you need to cut a sheet of plastic, PVC, PET and other types are suitable. Due to the fact that the vacuum cleaner does not create a very high vacuum, it will not work to use thick plastics. The thickness of the plastic for this homemade product should be in the range from 0.1 to 0.4 mm.
The sheet of plastic must be nailed with staples, maintaining a distance of at least 2 cm between them. You don’t need to feel sorry for the staples, since heated plastic can easily break out of their fasteners.

Now you can put the plastic in an oven heated to 190 degrees (for each type of plastic there is an optimal softening temperature). After a while, the plastic will heat up and begin to sag in the frame. Now it needs to be removed and installed on a vacuum machine. Subsequently, the vacuum cleaner turns on and the plastic begins to envelop the mold. When working, you need to use gloves, as the frame will be quite hot.

The vacuum cleaner should be allowed to work for about 20 seconds, then the frame can be removed to remove the product. If in some places the plastic does not adhere well to the shape, you can use a building hair dryer.