Cut the internal thread M10. How to cut threads

Threading is one of the main types of fastening of metal pipes, which can be reproduced independently. So, next we will consider which tool for cutting threads on pipes is worth purchasing, and how to use it. But before that, you need to decide basic concepts, without which the work will be impossible.

What should you know about carving?

• Depth- the distance from the base of the thread to the end of the pipe.
• Profile and its angle- cross-section of the coil, which is made in the form of a triangle, rectangle and other shapes. When the side edges of the coils intersect, an angle is formed.
• Step by step- the distance that is formed between the tops of the pipe or nearby turns.

Important: The larger the step, the greater the depth and number of turns per 1 unit. thread and therefore vice versa.

• Inch- appears as a triangle and is used when assembling elements water pipe, and sometimes - heating.
• Cylindrical- a version of an inch thread that has a smaller pitch. The smoothed top edge of the profile resembles a cylinder. An example of an external cylindrical thread diagram is presented below:
• Conical- the type allows you to obtain a hermetic connection, which is especially important when using sealing materials.
• Metric- type is used for pipes of small diameters. Can be trapezoidal - external corner It is done at 30 degrees, and the sides of the turns resemble a trapezoid. For bolted connections Rectangular threads can also be used, as they make the fixation more reliable. Here is the diagram metric thread, which looks like an equilateral triangle:

Preparing to Carve by Hand

• It is recommended to clean the pipe at the thread cutting site from paint, dirt and rust (only metal should remain);
• if the pipe has a chamfer, you need to carefully remove it with a file (or a grinder, if you have the skill to work with this tool);
• During operation, the surface of the pipe and the cutter must be lubricated with a special substance (it must be smeared both at the beginning of work and during the process).

If you do not follow these rules, the service life of the tools is sharply reduced, and there is also a high chance of rejecting or simply breaking the pipe itself.

Step-by-step instructions for cutting threads using a die

• Firmly install the pipe vertically. It must also be prepared - cleaned of paint, chamfers, etc. Ratchet handle for cutting pipe thread hold a suitable sized tool and apply lubricant to the pipe.
• Place the die strictly perpendicular to the pipe. If there is a deviation of even 5-10 degrees, the pipe will already be damaged.
• Start moving the holder handle clockwise.
• When required space will be covered with threads, lift the cutter up and again go down over what has already been cut so that the notches are clearer.

Remember to periodically lubricate the cutter and pipe. Act smoothly and calmly. Do not pull the die while working and do not leave the process unfinished.

Threading set for pipes and rules for its use

• Sliding. As a rule, they consist of incisors, the distance between which can be adjusted. Allows you to cut threads in several approaches, accurately and efficiently.
• Monolithic. The tool has a cylindrical shape with an internal hole and is installed in a die holder. Allows you to make carvings in one go.

Sets and individual components vary greatly in price and quality. Eat budget options sets for 1000 - 1100 rubles, and there are much higher ones.

• the clamp is installed in the ratchet;
• oil is applied to the cutting part;
• a guide is installed on the edge of the pipe;
• the ratchet rotates, making threads;
• During operation, the edges and pipe are treated with oil.

It is necessary to change the die on time - it must always be sharp, and all other elements must be in good working order.

Threading a pipe near a wall

Important! The cut on the pipe must be made perfectly even, otherwise cutting the thread will be extremely difficult.

How to cut internal threads?

• Zabornoy. Used directly for cutting;
• Calibrating. The middle part is necessary for guidance during sizing and cutting;
• Tail. The part has a square head and is used to hold the tap in the driver when cutting.

Gutter cutting machine

The diameter of the workpiece and the cutting pitch are adjustable. The operation of the spindle can be carefully debugged by adjusting the number and speed of revolutions. In principle, such a machine does almost all the work. Also, unlike manual lechers, the machine can make not only external threads, but also internal ones. More modern devices can process the smallest details and products with thin walls.

In the following video you can clearly see how the machine works without distortions:

Video: Manual thread cutting in a country workshop

1. Preparatory work

The drilled hole in which the thread is cut with a tap must be machined or processed with a countersink. The diameter of the drill should be larger than the internal diameter of the thread, since when cutting a thread the material is slightly “squeezed out”. For hard and brittle metals, the difference between these values ​​is less than for soft and ductile metals. For hard ones, for example, 6.7, and for soft ones - 6.8.

If we drill a hole with the same diameter as the internal thread, then the teeth of the tap will overheat due to high friction and build up metal due to the material squeezed out during cutting. As a result, we will get a torn thread or simply break the tap.

If you drill a hole larger than the required diameter, you will get an incomplete thread.

2. Internal thread cutting

After the preparatory work, the workpiece is secured in a vice and a tap is inserted vertically into its hole using a square.

Pressing the knob against the tap with your left hand, turn it to the right with your right hand until the tap cuts into the metal on several threads and takes a stable position, after which the knob is taken by the handles with both hands and rotated with the hands intercepted every half turn

In order to facilitate the work, the driver with the tap is rotated not all the time in a clockwise direction, but one or two turns to the right and half a turn to the left, etc. Thanks to this reciprocal rotational movement of the tap, the chips break, they turn out short (crushed), and the process cutting becomes much easier.

Having finished cutting, turn the knob in the opposite direction to unscrew the tap from the hole, then drive it through.

3. Rules for tapping threads

1. When cutting threads in deep holes, in soft and tough metals (copper, aluminum, bronze, etc.), the tap must be periodically unscrewed from the hole and the grooves must be cleared of chips;
2. The thread should be cut;
3. Cutting a thread immediately with a medium tap without a roughing pass and then a finishing one does not speed up, but, on the contrary, makes the work more difficult. In this case, the thread turns out to be of poor quality, and the tap may break. The middle and finishing taps are inserted into the hole without a driver, and only after the tap passes correctly along the thread, a driver is put on the head and threading continues;
4. The blind hole for the thread must be made to a depth slightly greater than the length of the part being cut, so that the working part of the tap extends slightly beyond the part being cut. If there is no such reserve, the thread will be incomplete;
5. During the cutting process, it is necessary to carefully ensure that there is no misalignment of the tap; To do this, every 2-3 cut threads you need to check the position of the tap in relation to the upper plane of the product using a square. Particular care must be taken when cutting threads in small and blind holes;
6. The quality of the thread and the durability of the tool are affected by right choice cutting fluid

Instructions

A thread is essentially a helical groove cut into the outer or inner cylindrical surface. It is mainly used to connect various parts to each other. In mechanical engineering it can be used to convert translational motion into rotational motion and vice versa. There are two types of threads, such as metric, with a profile angle of 60o and pipe thread, with an angle of 55o.
In metric, the diameter and pitch of a thread are measured in millimeters. When designating metric threads, alphabetic and numeric threads are used, for example M8x1.5. The number eight corresponds to the diameter of the thread, and 1.5 means the thread pitch, turns.
In inch threads, measurements are taken in inches and numbers per inch. One inch is equal to 2.54 cm. For example, an inch is written as 1 1/4".

To cut an external thread, you need to take a die of the required size and prepare a workpiece, and in particular, select a workpiece of a certain diameter. The diameter of the workpiece for thread cutting is determined according to the tables. In practice, for cutting, for example, a thread with a diameter of M6, a rod with a cross-section of 5.92 mm is required, that is, approximately one tenth of a millimeter smaller; for an M8 thread, the workpiece must have a diameter of 7.9 mm.
Here, as an example, is an extract from the table of rod diameters for metric threads:

Thread diameter/rod diameter (mm) - 5/4.92; 6/5.92; 8/7.9; 10/9.9; 12/11.88; 16/15.88; 20/19.86; 24/23.86
After selecting the workpiece, it is clamped in a vice, a file is used to chamfer the end so that the die fits correctly, and the thread is cut using rotary-pressing movements, not forgetting to lubricate the part with machine oil.

The internal thread is cut with a tap. Previously drilled holes should be smaller than the diameter of the thread you need. An extract from the table of drill diameters for drilling holes is given below.

Thread diameter/hole diameter (mm) - 2/1.6; 3/2.5; 4/3.3; 5/4.2; 6/5.0; 8/6.7; 10/8.4; 12/10.2; 16/13.9; 20/17.4; 24/20.9
To cut threads inside a part, you need to have two taps, roughing and finishing.

We also clamp the part into a cleat and, using rotational movements and slight pressure, cut the thread with a rough tap, periodically lubricating the tap with machine oil, then make a finishing pass. The thread is ready for use.

note

To obtain a better quality thread, turn the wrench 180° clockwise, and then 90° counterclockwise. Thanks to this, long chips are cut off and the force on the knob is reduced.

Sources:

• how to cut a thread with a tap

Many years ago, when the era of fasteners was just beginning, making a nut was a task only possible for a highly skilled craftsman. Today, internal thread cutting is a routine operation. However, to perform it well, you need to have certain knowledge and skills.

You will need

• Electric drill, set of drills and taps, thread gauge, caliper, table of metric thread sizes.

Instructions

Decide on the parameters of the thread to be cut. There are many types of threads, but most often we have to deal with metric threads, which are characterized by two parameters - diameter and pitch. If there is a bolt for which you need to cut an internal one, measure its parameters. The diameter of the thread is measured with a caliper, the pitch - with a thread gauge. If you do not have a thread gauge, the thread pitch can be measured in the following way. Press the threads of the bolt onto a clean piece of paper and roll it so that the threads are imprinted on the sheet. Count how many turns there are on a certain length and divide that length by the number of turns. The resulting value will be the approximate thread pitch. Select the nearest standard pitch value from the table of metric thread sizes.

Determine the diameter and depth of the hole that needs to be made for threading. To determine the diameter, use the same table that was used to determine the standard pitch. The required parameter is usually designated d1 or D1. If the thread is cut in a blind hole, it is also necessary to determine the drilling depth of the hole. It should be greater than the threading depth by a certain amount, which depends on the design of the tap. Measure the length of the cutting (chamber) part of the tap and add it to the required thread depth. This will be the required drilling depth for the hole.

Drill a hole of the required diameter to the required depth. If the diameter of the existing drill does not match the hole diameter determined from the table, take the drill closest in diameter. However, keep in mind that the difference between the drill diameter and the standard hole size should not be significant compared to the thread pitch. After drilling a hole, make a small chamfer in it with a drill larger diameter.

Cut the thread To do this, attach the tap to the driver, insert it into the hole and, pressing the tap firmly against the hole, give it a rotational movement. At the same time, try to maintain a perpendicular position of the tap in relation to the surface of the part. When the tap is securely inserted into the hole, you can limit yourself to one rotational movement.

Video on the topic

note

If the tap has two versions - finishing and roughing - first cut the thread with a roughing tap and then with a finishing one.

Helpful advice

To make threading easier, you can drop a few drops of machine oil into the hole.

When cutting threads, turn the tap out from time to time to remove chips.

When performing technical drawings, quite often you have to deal with the image of standard fasteners. Many of them have carvings, which have to be depicted in the drawing. The main parameters of the thread include the outer and inner diameters, as well as the pitch.

You will need

• - paper;
• - compass;
• - ruler;
• - pencil
• - table of bolt standards.

Instructions

Select the outside diameter of the thread. IN technical documentation it is usually denoted as d without a subscript. It is equal to the diameter of the cylinder on which the thread is applied. The inner diameter is d1. Both the length of the cylindrical part and the size of the area on which the thread is applied are important.

A cylinder depicted on a plane looks like a rectangle. Draw the cylindrical part of the bolt. The width of the part is equal to the diameter of the cylinder, and the length corresponds to the length of the part. Draw midline, dividing the short sides of the rectangle in half.

On the long sides from one end, set aside the length of the thread. Place the dots and connect them with a thin line. From the point where it intersects with the midline, set aside the size in both directions, equal to half internal diameter. Do the same on the short side, which is the beginning of the thread. Connect the pairs of points obtained with thin lines. Both thread diameters must be indicated on the drawing.

This method is used when drawing a projection in which a cylindrical rod is visible at the fastener. Other projections may show, for example, the head of a bolt or screw. Draw a hat of the desired shape and determine its center. Place a compass needle at this point and draw a circle whose radius is equal to the outer radius of the thread. Draw a second circle from the same center. Its diameter should be equal to the internal diameter of the thread, which is indicated by a thin line. Indicate both diameters on the drawing. The line used to draw the inner circle is usually not closed.

The thread can also be internal. Draw a hole on the corresponding projection of the part. As in the first case, on some projections it will look like a rectangle, on others - like a circle. The thread also has two diameters, and in this case the inner one will be larger than the outer one. Draw a cylindrical hole in the form of a rectangle. Its width corresponds to the outer diameter of the thread. Draw the middle line in the same way as in the first method. From the intersection points, set aside the size of the inner radius in both directions. Set aside the same sections along the line where the thread begins. Connect the dots in pairs with thin lines.

On the projection where the hole should look like a circle, draw a circle of the appropriate diameter and circle it. From the same center, draw a second circle with a thin line, the radius of which is equal to the internal radius of the thread.

note

Learn to read labels. It consists of a letter and several numbers. The letter indicates the type of thread. For example, M is a metric thread. Next comes the designation of the internal diameter. The large step is not indicated, and the size of the small step is indicated after the “x” icon. Left-hand threads are marked with the letters LH.

The question of how to cut a thread with a tap arises in cases where a pre-made hole needs to be prepared to accommodate a bolt, screw, stud or any other type of threaded fastener. In such situations, it is the tap that is the main tool that allows you to quickly and accurately cut internal threads with the required geometric parameters.

Types and areas of application of taps

Internal thread cutting can be done manually or using machines various types(drilling, turning, etc.). The working tools that perform the main work of cutting internal threads are machine-hand or machine taps.

On different kinds Taps are divided depending on a number of parameters. The following principles for classifying taps are generally accepted.

1. According to the method of rotation, a distinction is made between machine-manual and machine taps, with the help of which internal threads are cut. Machine-hand taps equipped with a square shank are used in conjunction with a special device with two handles (this is the so-called tap holder). With the help of such a device, the tap is rotated and cuts the thread. Thread cutting with a machine tap is carried out on metal-cutting machines of various types, in the chuck of which such a tool is fixed.
2. Based on the method by which internal threads are cut, a distinction is made between universal (through) taps and complete taps. The working part of the former is divided into several sections, each of which differs from the others in its geometric parameters. The section of the working part that first begins to interact with the surface being processed performs rough processing, the second - intermediate, and the third, located closer to the shank - finishing. Cutting threads with complete taps requires the use of several tools. So, if a set consists of three taps, then the first of them is intended for roughing, the second for intermediate, and the third for finishing. As a rule, a set of taps for cutting threads of a certain diameter includes three tools, but in some cases, when products made from special hard material, sets consisting of five tools can be used.
3. According to the type of hole inner surface which needs to be threaded, there are taps for through and blind holes. A tool for processing through holes is characterized by an elongated conical tip (approach), which smoothly passes into the working part. Universal type taps most often have this design. The process of cutting internal threads in blind holes is carried out using taps, the conical tip of which is cut off and performs the function of a simple milling cutter. This design of the tap allows it to cut threads to the full depth of a blind hole. For thread cutting of this type As a rule, a set of taps is used, driven manually using a crank.
4. According to the design of the working part, taps can have straight, helical or shortened chip removal grooves. It should be borne in mind that taps with grooves of various types can be used for cutting threads in products made of relatively soft materials– carbon, low-alloy steel alloys, etc. If threads need to be cut in parts made of very hard or viscous materials (stainless, heat-resistant steels, etc.), then taps are used for these purposes, the cutting elements of which are arranged in a checkerboard pattern.

Taps are usually used for cutting metric threads, but there are tools that can be used to cut pipe and inch internal threads. In addition, taps also differ in the shape of their working surface, which can be cylindrical or conical.

Preparing to cut internal threads

In order for the process of cutting internal threads using a tap to not cause any particular difficulties and result in a high-quality result, it is necessary to properly prepare for this technological operation. All methods of cutting threads using a tap assume that a hole with the appropriate diameter has already been made in the workpiece. If the internal thread to be cut has standard size, then to determine the diameter of the preparation hole, a special table with data in accordance with GOST can be used.

Table 1. Diameters of holes drilled for standard metric threads

If the thread that needs to be cut does not belong to the standard category, you can calculate the diameter of the hole to make it using a universal formula. First of all, it is necessary to study the marking of the tap, which must indicate the type of thread being cut, its diameter and pitch, measured in millimeters (for metric). Then, to determine the cross-sectional size of the hole that needs to be drilled for the thread, it is enough to subtract the pitch from its diameter. For example, if a tool marked M6x0.75 is used to cut a non-standard internal thread, then the diameter of the preparation hole is calculated as follows: 6 – 0.75 = 5.25 mm.

For standard threads belonging to the inch category, there is also a table that allows you to choose the right drill with which to carry out the preparatory work.

Table 2. Diameters of holes drilled for inch threads

An important question to obtain a high-quality result is not only the question of what is used to cut the thread, but also what drill to use to make the preparation hole. When choosing a drill, you need to pay attention to the parameters and quality of its sharpening, as well as to ensure that it rotates in the chuck of the equipment used without runout.

The sharpening angle of the cutting part is selected depending on the hardness of the material that needs to be drilled. The higher the hardness of the material, the greater the sharpening angle of the drill should be, but this value should not exceed 140°.

How to cut threads correctly? First you need to select tools and consumables:

1. an electric drill or drilling machine capable of operating at low speeds;
2. a drill whose diameter is calculated or selected using reference tables;
3. a drill or countersink, with the help of which a chamfer will be removed from the edge of the prepared hole;
4. a set of taps of the appropriate size;
5. manual holder for taps (drivers);
6. bench vice (if the product in which the thread needs to be cut needs to be fixed);
7. core;
8. hammer;
9. machine oil or other composition, which during the processing process must be used to lubricate both the tap and the thread section being cut by it;
10. rags.

Features of the technology

When cutting internal threads with a tap, the following algorithm is used.

• In the place on the surface of the workpiece where the hole for threading will be drilled, it is necessary to form a recess for a more accurate entry of the drill, using a core and a regular hammer. The drill is fixed in the chuck of an electric drill or drilling machine, at which low tool rotation speeds are set. Before starting drilling, the cutting part of the drill must be treated with a lubricating compound: a lubricated tool enters more easily into the structure of the material being processed and creates less friction in the processing area. You can lubricate the drill with a piece of ordinary lard or grease, and when processing viscous materials, machine oil is used for these purposes.
• If threading is necessary in details small size, they should first be fixed using a bench vice. When starting drilling, the tool fixed in the equipment chuck must be positioned strictly perpendicular to the surface of the workpiece. You should lubricate the tap regularly and ensure that it does not warp and moves strictly in the given direction.
• At the entrance to the hole, as mentioned above, it is necessary to remove the chamfer, the depth of which should be 0.5–1 mm (depending on the diameter of the hole). For this purpose, you can use a larger diameter drill or countersink, installing them in the chuck of drilling equipment.
• The process of cutting internal threads begins with tap No. 1, which is the first to be installed in the driver. We should not forget about the lubricant, which must be applied to the tap for threading. The position of the tap relative to the hole being machined must be set at the very beginning of the work, since later, when the tool is already inside the hole, this will not be possible. When cutting a thread with a tap, you must adhere to the following rule: 2 turns of the tap are made in the direction of cutting the thread, 1 - against the direction. When the tap makes one revolution back, chips are thrown off its cutting part and the load on it is reduced. Thread cutting with a die is performed using a similar technique.
• After cutting the thread with tap No. 1, tool No. 2 is installed in the driver, and after it – No. 3. They are processed according to the method described above. When cutting threads with taps and dies, you need to feel when the tool begins to rotate with force. As soon as such a moment occurs, you should turn the knob in the opposite direction to throw the chips off the cutting part of the tool.

Every person involved in the installation of metal structures or performing various tasks should know how to cut a thread manually with a tap. renovation work. This is one of the basic skills of plumbing, which experienced workers have brought to automaticity.

Taps are designed to be grasped by a rotating tool (wrench) or secured in a machine chuck.

Basic tool

For making internal threads manually Various taps are used, made from carbon or high-speed steels. They represent metal rod With working part and a shank designed to be grasped by a rotating tool (wrench) or secured in a machine chuck. The working part with external thread has a conical shape; it has longitudinal grooves for the exit of chips.

There are several types of taps, but not all of them are suitable for manual internal threading. For example, machine ones can only be used on machine tools due to their design. For production handmade The following types of taps are suitable:

1. Complete. From the name it follows that this is a set of several products (3-5 pieces) of the same diameter, used alternately. They allow you to achieve a clear thread profile, although the operation takes some time.
2. Machine-manual. A type of machine tool in which the end of the shank has a rectangular cross-section to be grasped by a wrench. The thread is cut in one pass.

In addition, taps can have different designs depending on the type of thread. The most common are metric, less often - cylindrical and pipe.

As a rule, when installing metal structures industrial buildings(hangars, greenhouses and other structures) not subject to vibration, metric threads are used.

Also, some taps are made with a cut-off working part, this is necessary for working with blind holes. Separate consideration should be given to working with alloy steels of increased hardness. Products to overcome this hardness have grooves on the working part, arranged in a checkerboard pattern or crosswise.

Return to contents

Drill selection

An electric drill is necessary to perform internal threading work.

Before cutting a thread with a tap, you must first drill a hole for it. It is clear that the hole diameter should be smaller size tap, but how much? Exists universal method calculating this difference. Any thread is characterized by two parameters:

• diameter, indicated on instruments with capital letter M in front, for example, M6;
• The pitch of turns is written as a number after the first parameter, for example, M6x1.

By looking at the markings on the tap, it is easy to select the drill for the job. It is necessary to subtract the thread pitch from the diameter value; in the given example, M6x1, you will need a hole measuring 6 - 1 = 5 mm. The drill should be a regular cylindrical one; for metal processing these are made from high-speed steel R6M5. In order to facilitate the selection of sizes, Table 1 presents the recommended diameters for the holes of the most common metric profile threads.

Table 1

Because the we're talking about about manual metal processing, then when selecting drills, one feature should be taken into account. When working with an electric drill, no matter how hard you try to keep it level and motionless, the hole will break and its size will be slightly larger than necessary. As a result, after passing with a tap, the thread turns will have a cut profile. When the bolt is screwed in, there will be some play, and if the tightening torque is high, the coils may simply become deformed. The size of the hole depends on two factors:

Countersinks are needed for chamfering when cutting internal threads.

1. The larger the diameter, the more the hole unfolds. For example, with D = 5 mm there is an increase of 0.08 mm, and with D = 10 mm there is already an increase of 0.12 mm.
2. Working conditions. The mechanic may be in an awkward position or at a height, this will cause increased hole breakdown, which will then affect the quality of the connection.

The problem is solved as follows: to make the internal thread full-profile, you must initially take a drill whose diameter is 0.1 mm less than the required one. It is possible that in some cases it will be difficult to rotate the tap, but usually no difficulties arise.

Preparation of tools

To perform internal thread cutting you will need:

• marking tools (tape measure, ruler, pencil);
• electric drill with a set of drills;
• countersink for chamfering;
• a set of taps with a manual crank;
• hammer;
• core

Drills should be threaded (sharpened) in accordance with the hardness of the material being processed. The harder it is, the greater the sharpening angle needs to be maintained. When drilling and cutting, the working parts of drills and taps must be lubricated. The choice of lubricant type depends on the viscosity of the steel. For regular and carbon steel, old lard or grease is suitable, for stainless steel - machine oil.

Return to contents

Work procedure

In order to correctly perform the entire range of thread cutting work, it is recommended to adhere to a certain sequence. This is important when you need to provide a good hundred connections as during assembly metal structures. You need to start with marking, which is done using a tape measure or ruler in accordance with the drawing. Having measured the indicated distances from the base sides, place a mark with a pencil at the found point. Marking is done for all holes at once or for those that the worker can reach while at a height.

Next, having pointed the core at the intended location, apply one calculated and precise blow to create a clear depression. Naturally, before starting the procedure, the core must be sharpened properly. In the same way, you need to mark all the locations of future holes. The drill bit is then secured in the drill chuck and lubricated, after which you can begin making the hole. The speed of the drill must be adjusted in advance so that it is low.

Drilling is done carefully, with medium pressure, holding the drill without distortion at an angle of 90° to the surface. Do not allow the power tool to wobble in different sides, this enhances the hole breakdown. It should be taken into account that at the moment the drill comes out from the other side, some force and a slight increase in the number of revolutions will be required. If the metal is thick, then the working part must be lubricated several times during the process. When all the holes are ready, a countersink is inserted into the chuck and chamfered.

The last stage is thread cutting. The sequence of this operation is the same for all types of taps. Having clamped it in the driver and pre-lubricated it, the end of the tool is inserted into the hole, also maintaining an angle of 90°. Lightly pressing the knob from above so that the first turns of the working part can catch on the edge of the chamfer, make the first turn. Further rotation occurs without pressure according to the algorithm: one revolution forward, half a revolution back to discharge chips. With machine taps that perform threads in one pass, you must act carefully: the tool is fragile and breaks easily. Complete products are easier, but here you need to run the thread with the first number, then the second, and so on.