Pipe die for cutting threads on pipes | My tools
A pipe clamp is a tool that is used to cut threads on steel pipes. Steel pipes have long since faded into the background (but have not disappeared completely), and today plastic is often used when installing plumbing for heating systems.
Working with plastic is much simpler and easier, but steel pipelines are still used in heating and plumbing systems. It is not uncommon to find yourself needing to cut a thread on a steel pipeline to connect it to another part of the pipe or fitting.
For such purposes, a thread-cutting tool is used - a pipe die or die.
Many people don’t even know about the existence of thread-cutting dieheads, so after reading the name “thread-cutting diehead,” the question immediately arises, what is it? A pipe clamp is a device used for cutting threads on metal pipes. This device resembles a die (die), which is used to cut threads on cylindrical parts.
The design of the die is simple and is a cylindrical part with a recess for removing metal shavings from the device when cutting threads. The tool is also equipped with a special handle and a device for installing nozzles of different diameters. The basis of such a device are cutters or combs made of durable types of alloy steel. Not only the efficiency of the device, but also its service life depends on the quality of the steel used to make the die.
Many people do not understand how a die differs from a die. The difference is that the die has a die - cutters. The presence of a holder and handle ensures effective operation of the tool. For the manufacture of the component elements of the die, conventional types of steel are used, with the exception of cutters. The cost of the tool depends on the quality of the steel used to make cutters.
Jig for cutting threads on a pipe
This is useful! Reviews show that purchasing a die that costs less than 4,000 rubles is not an effective waste of money. For the manufacture of cheap pipe clamps, low-quality steel is used, as a result of which it is impossible for the device to cut threads even on one pipe.
Types of clamps for cutting threads on pipes
Pipe clamps continue to be popular, so manufacturers produce different types of products:
- Simple handicrafts
- Ratchet attachments
- Electrical plugs
How do the products differ, and what is the best option to choose for cutting threads on a pipe?
- Simple dies are a regular die fixed in a holder (base). This die can be used either together with the handle or separately. The device can be rotated using an ordinary handle or a gas key. It is rational to use a simple pipe clamp only when it is necessary to cut a thread in a single copy. Manual clamp with two handles and a regulator.
- Ratchet tool. For those who want to have an indispensable thread-cutting tool in their arsenal, it is recommended to purchase a device with a ratchet. Typically, such a wrench is sold in a set that contains dies or attachments of various diameters: ½, ¾, 1, 2 inches, etc. The advantage of a ratchet is that it simplifies the process of using the tool. If you need to cut threads on a pipe with a ratchet socket, then this can be done with one hand, making simple reciprocating movements Ratchet socket: an easy-to-use tool
- Electric clamp - this type of tool is effective in cases where you need to cut threads on pipes in large quantities. The main disadvantage of this type of tool is its exorbitant cost, amounting to about 25 thousand rubles. The design of the electric clamp is based on an electric motor capable of developing high torque and low speed. The electrical device resembles a grinder in appearance, only instead of a circle, a die for cutting threads of the corresponding pipe diameter is installed in the spindle. Electric die for cutting threads
If you need to cut threads on a pipe in a small volume, then you can buy an electric plug, but it will not be a rational waste of money.
The main advantage of a hand ratchet and a power tool is the ability to cut threaded connections on pipes fixed near a wall or laid in the ground.
To cut threads on steel heating or water supply pipes, you do not need to dismantle them from the system. To do this, you need to pick up a tool and begin to quickly obtain a spiral-shaped connection.
How to choose a pipe clamp for threading a pipe
The task of the tool is to make a threaded connection on steel pipes. This result can only be achieved by using high quality dies.
Even if there is a need for thread cutting in a single quantity, then buying a cheap clamp (set with a ratchet) is not the best option. In this case, it is better to buy a pipe clamp without a ratchet, which will be of high quality than the dies in the set.
Many people step on such a rake when the opportunity arises to purchase a whole set of pipe threading dies instead of one die.
When purchasing pipe cutting dies, you need to pay attention to a number of the following parameters:
- Price. Sets of cheap screws in a set are like cheese in a mousetrap. The probability that you will not be able to cut a thread with such a tool even on one copy is 99.9%
- Possibility of changing cutters. Most manufacturers leave the opportunity to change the cutters while continuing to use the tool. Sooner or later, cutters will become dull and fail (even from high-quality steel), so the ability to replace them is a great advantage
- Material for making cutters. If you buy a set, it must come with instructions, as well as the technical parameters of the tool. Cutters must be made of high-quality durable and alloy steel, which affect the ability to cut threads in large quantities
- The set contains dies for threading pipes of different diameters. If you often work with pipes with a diameter of more than 1 inch, then you need to look for the appropriate set
- Manufacturer. To ensure the quality of the tool, you need to buy devices only from trusted manufacturers. The most popular manufacturers of pipe clamps are: YATO, Zubr, SIBRTECH, Truper and others
How to properly cut threads on a pipe with a pipe clamp
Before using the tool, you need to understand some nuances. Externally, the tool does not cause any difficulties - install a die of the appropriate diameter, and cut your own thread. However, not all so simple! Before threading, you need to prepare for this event. The procedure in the form of instructions for cutting a threaded connection is as follows:
- Rolling the pipe. A mandatory procedure, as this will help simplify the process of cutting a spiral joint. Rolling is a reduction in the outer diameter of the pipe by several millimeters. This is done by using a file, turbine, anvil and hammer, as well as a gas wrench. Craftsmen use a grinder with a grinding wheel for rolling
- Treat the rolled section of the pipe with any type of lubricant - Litol or Solidol. The same materials can be used to treat cutters, which will help extend their service life by reducing cutting resistance
- If threading is performed on a pipe that is located next to a wall or in the ground, you need to secure it with a gas wrench to avoid damaging the integrity of the fastening of the second end of the pipe. If the pipe is not secured, it must be clamped in a vice, and only then begin processing
- Cutting is performed with slow reciprocating movements, since high speed will lead to tool failure
- Having put a die on the pipe, it is necessary to install it strictly perpendicular to the end part of the material, that is, align the position of the die relative to the pipe
- Using slow movements, you need to cut the first turn, which is the main one. When slicing, you need to make one revolution forward and then go back 0.5 revolutions. Metal shavings will be removed during the return process.
- As soon as the first turn is cut, further use of the tool is facilitated and consists only of performing reciprocating movements
After this, the die is unscrewed and the quality and integrity of the resulting thread is checked. You can screw the coupling onto it, checking the quality of screwing. How many turns of pipe are needed for a reliable connection? Every master asks this question when using a similar tool. The number of turns is the same as on the cutter or on the coupling.
It is important to know! During the cutting process, you should not rush, otherwise all your efforts may lead to dulling of the cutters on the tool. Do not use a die on which the cutters are damaged or ground off, as this may lead to damage to the integrity of the pipe.
If you need to cut a thread on a pipe that is located in the wall, when access is only from the end part, then you will need to use a special extension adapter, as shown in the photo below.
Cutting threads on a pipe in the wall using a die with an adapter
Many may think, why buy a die if you can turn to a turner who will cut threads of any size, diameter and shape. The tool is mainly designed for exceptional cases where threads need to be cut on site. This device is really very convenient to use, it always helps to solve problems with a steel pipeline when the need arises to make a threaded connection.
If you prefer welding instead of a threaded connection, then you should understand one important nuance - when welding, a section is formed inside the pipe that will cause the accumulation of blockages. If the weld is applied poorly, a leak may occur over time, so the only correct solution is to buy a pipe clamp and cut the threaded turns in the required quantity.
Source: https://moiinstrumentu.ru/trubnyj-klupp-instrument-dlja-narezki-rezby.html
Features of thread cutting with a clamp
Threaded connections have been weakening in recent years. This is due to the advent of plastic pipes that are connected by soldering. However, a certain part of the pipelines is assembled using old technologies. To make a high-quality connection of metal pipes, you can cut the thread with a clamp.
Basic cutting methods
To make carvings on metal pipes, three methods are used, which involve the use of different tools:
- Using a lathe. It is possible to process products of different diameters.
- Die (second name - lerka).
- Klupp - a hand or electric tool.
Taps are used to process the inside of products.
What is a klupp?
Pipe clamps can be compared to dies. They are a monolithic tooling that allows you to cut precise grooves on metal of the desired shape. However, the solidity of the structure creates serious stress when processing large-diameter pipeline elements. You can relieve stress by making the die body less durable. But this will reduce the hardness of the incisors, causing them to quickly become dull. To extend the service life of the blade before sharpening, the equipment is equipped with a spring mechanism.
The klupp is not much different from the die familiar to plumbers. It consists of a cylindrical body made of metal with holes for removing chips. There are separate clamps around the perimeter of the metal ring to securely hold the equipment on the pipe. The incisors arranged in a certain order are fixed on the inside.
Advantages of a die over a simple die
When comparing a die with a die, a person without experience will not find any serious differences. However, the second option of equipment has certain advantages:
- The equipment has fewer non-functional parts, the price is reduced.
- Comes with a cheap holder and durable teeth.
- The cutters are removable. This makes it possible to change working parts when each of them fails without purchasing the entire tool.
- Allows you to process large workpieces using less effort.
It is impossible to say objectively whether lerki klupps are cheaper or not. The second option can be found in stores for hundreds of dollars. The main advantage of these tools is ease of use and the use of less effort. Thanks to this, the quality of work performed improves and efficiency increases.
Varieties
Before purchasing a tool for creating threaded connections, you need to consider the different models that construction stores present to customers. There are three types of equipment, which differ in design and control.
With ratchet and one handle
The ratchet tool is similar to a wrench with interchangeable heads, which is used when repairing cars. The mechanism allows you to cut threads faster, spending less effort and time. However, ratchets have some disadvantages:
- The ingress of dirt, dust, debris, and liquids into the mechanism impairs its performance. Over time it breaks down. It is necessary to follow the rules for storing and caring for the ratchet so that it lasts longer.
- Low quality of materials used in the manufacture of most ratchet models.
- Strong types of alloys can damage the moving mechanism. The device will have to be replaced.
A cheaper, more reliable analogue can be a gas key.
With adjustable head
Plumbers often carry with them a set of replacement heads, a holder, and additional accessories. The assembly weighs quite a bit, which makes it difficult to carry. Therefore, models with adjustable heads were developed. The mechanism allows you to change the diameter of the working part. This will expand the functionality of the equipment, allowing you to carry fewer parts for work.
Electrically driven
Professional models are equipped with an electric drive. Electrical equipment has a number of strengths and weaknesses. Advantages:
- Ability to work with pipeline elements of different diameters.
- Minimum effort is required during operation.
- Increased cutting speed.
Flaws:
- Weighs more than a hand tool and takes up a lot of space.
- Requires a network connection.
Pipe clamp selection criteria
There are many different models of thread cutting dies. They differ in different parameters, design, and sizes. When choosing, you need to consider the following features:
- Do not buy expensive models for home workshops.
- The cheapest tools will quickly fail. They are suitable for one-time work.
- Pay attention to the size and shape of removable incisors. They do not always fit equipment from other manufacturers.
- It is advisable to choose sets of working heads with different diameters.
- When choosing the material for the working part, give preference to alloy steel.
When calculating the power of electric models, you need to take into account the type of metal or alloy being processed.
How to cut threads on a pipe?
Using a hand tool involves following a certain sequence of actions. Pipe threading:
- Clean work surfaces from dirt and decorative coatings. To do this, you can use a grinding machine or sandpaper.
- Clamp the pipe with a vice to keep it stationary.
- Grease your work surface with olive oil.
- Unscrew the clamping bolts from the equipment.
- Place the nozzle on the pipe. Slowly tighten the clamping bolts.
- Secure the guides in place.
- Install cutting parts.
- Under light pressure, begin to twist the tool clockwise.
Cutting should be done with smooth movements, without jerking, so as not to spoil the thread. The equipment is removed after unscrewing the locking bolts.
There are several features that need to be studied before creating a threaded connection:
- Pipes that are connected to the general piping system must be held with a gas wrench when creating the connection. This is necessary to prevent rotation of the product.
- It is easier to cut a place greased with grease. Cutters become less dull after adding lubricant.
- It is advisable to buy cutters from the same company as the holder. If firms differ, the working parts may not fit into the overall design.
- Before starting work, check the sharpness of the cutters. Blunt edges can ruin the surface of the metal.
- During work, you can change the position of the working parts, which allows you not to remove the structure until the work is completed.
- Use a special cooling lubricant that will prevent the cutters from overheating.
After creating a connection on two pipeline elements, it is necessary to check how well the individual parts fit together. If a misalignment occurs, the pipes will not be able to connect.
Threaded connections are still used today. They can be made using dies, clamps, and lathes. The second option is considered more convenient when compared with other hand tools. It is important to choose high-quality working parts and check their sharpness before carrying out work. High-quality cutters are made from alloy steels.
Features of thread cutting with a clamp Link to main publication
Source: https://metalloy.ru/obrabotka/rezba/narezka-kluppom
How to cut a thread manually with a tap correctly: tool classification and basic recommendations
A variety of tools can be used for cutting threads, among which we highlight a tap. It is used to create a threaded surface designed to accommodate a screw, stud, bolt, or other fastener. Relatively low cost and ease of use determined the widespread use of the hand tool in question. Let's take a closer look at how to properly cut a thread with a tap at home.
Lathes or drilling machines have been used for cutting threads for quite a long period. They are designed to rotate a workpiece or tool. In almost all cases, the working tool is a tap.
The classification of such a tool is carried out according to a number of different characteristics:
- Depending on the method of driving them into rotation, they can be divided into machine or machine-hand taps. A special feature of the machine-manual variety of the tool is the presence of a square shank, which is suitable for a holder with two handles. Thanks to such a holder, you can rotate the tool and cut threads. As for the machine variety of the tool in question, it is installed in the chuck of various machines and can have a shank of various shapes and sizes.
- There are universal and complete taps based on characteristics related to the specific application. The universal version has a working part, which is divided into several sections. They differ from each other in geometric shape, the first is intended for roughing, the second and subsequent ones are for bringing the surface to a suitable state. The complete version is designed for the phased use of several taps. As a rule, a set for cutting threads in ordinary metal is represented by three tools, and for processing hard alloys - five.
- Taps are classified based on the type of hole being machined: blind or through. To work with through holes, a tool with an elongated conical tip is used, which is a continuation of the working part. Universal taps often have this type of shape. If you need to cut a thread in a blind hole, then use a tool that has a cut tip resembling a milling cutter. Due to this shape, it is possible to cut threads along the entire length of the hole.
- Thread cutting tools are also classified according to the type of working surface. Examples include helical, straight or shortened grooves. On sale you can find a version that also has a combined surface. It is suitable for processing metals with low hardness. For hard alloys, a tool with cutting elements arranged in a checkerboard pattern is used.
As a rule, high-quality tool steel is used in the manufacture of tools. It can withstand long-term use and does not heat up during operation. A high quality tap has a strict geometric shape and looks neat. A similar tool is often used for cutting metric threads, but there are versions for producing inch threads. The shape of the base can be cylindrical or conical.
Preparatory stage
To ensure that the work of obtaining threads does not cause many difficulties, careful preparation should be made for such a technological operation. All methods used related to cutting internal threads assume that a hole of the required diameter has already been obtained in advance. You can obtain the standard thread size when creating a hole according to the correspondence table. For example, for an M10 thread, a hole with a diameter of 8.5 mm is created.
There is often a situation where it is necessary to obtain a thread of a non-standard size. In this case, the required hole diameter is calculated using a universal formula. Calculations are carried out as follows:
- The marking of the tool used is studied. You need to pay attention to the type of thread being cut, pitch and diameter.
- You can determine the required hole diameter when using an M5X0.75 tap as follows: 5−0.75=5.25 mm.
The easiest way to carry out the work is when you need to get a standard thread, since all the necessary information can be taken from various tables of regulatory documentation.
To get a quality hole, you need to choose the right drill. When drilling, it is recommended to use equipment that prevents runout during operation. When choosing a drill, it is worth remembering that it must have high-quality sharpening.
Experts recommend selecting the sharpening angle depending on the hardness of the material being processed.
As the hardness increases, the recommended sharpening angle also increases, but it should not exceed 140 degrees.
Manual tapping is only possible with the following tools:
- An electric drill that can operate at low speeds.
- A high-quality drill, the diameter and sharpening angle of which is selected from table values or calculated.
- To chamfer the edges of the hole, you will need a countersink or large diameter drill.
- One or a whole set (depending on the type) of taps of the appropriate size.
- A hand holder that is suitable for the tool used.
- A bench vise in which the product will be fixed. When cutting a thread, a certain layer of metal is removed, which is only possible when a lot of force is applied. If the workpiece or finished product is poorly fixed, the quality of processing will be low.
- Core and hammer.
- In order to simplify the task, it is recommended to use machine oil to lubricate both the tool itself and the surface being processed. If you do not use machine oil or another substance with similar properties, the process may be significantly delayed.
- Rags.
After finding everything you need, you can begin the actual work.
Features of the technology used
carry out the work in question with your own hands at home. To do this, you need to consider the recommendations below:
- Before creating a hole, it is recommended to make a small recess, which will ensure the correct entry of the drill. You can use a core for this. When drilling through metal, it is recommended to set the drill speed to low, which will allow you to achieve high quality processing. Before drilling, you can treat the cutting edge with a special compound, which will make it easier for the tool to enter the metal.
- At the time of creating the hole, the drill with the drill bit must be positioned strictly perpendicular to the surface being processed. When using the tap, the cutting edge should be constantly lubricated with engine oil, and you should also ensure that the tool is positioned strictly parallel to the axis of the hole created.
- In almost all cases, chamfering is carried out at the entrance of the hole, the size of which is 0.5-1 mm. To do this, you can use a countersink or a larger diameter drill.
- When using a set of taps, thread cutting should begin with tool No. 1. The direction of the thread should be strictly controlled at the very beginning of the work, since in the future it will be almost impossible to change the inclination of the tool used.
- To obtain high-quality grooves, it is recommended to make two turns along the thread and one in the opposite direction. The reverse rotation is done in order to remove chips from the cutting edge, due to which the stroke becomes smoother.
- After using tool No. 1, the second one is installed, and after a complete passage, the third one is installed. It is worth considering that with great force it is recommended to make one or several revolutions in the opposite direction, due to which the chips are removed from the cutting zone.
It is not recommended to apply a large load to the handle by using a lever or a gas wrench. Do not forget that the tap may burst due to high load, then removing the remaining part inside will be quite difficult. While working, the master must feel how the tool moves: easily or with great effort. The shape of the cutting edge does not allow removal of chips from the working part at the moment of rotation along the thread.
Source: https://tokar.guru/hochu-vse-znat/kak-pravilno-narezat-rezbu-metchikom-vruchnuyu.html
Cylindrical pipe thread - how to cut it yourself
Threading is the processing of a hole or rod element in a workpiece, in which a special tool is used to obtain a cut inside or outside. The cutting contains turns, protrusions, and alternating grooves in the shape of a spiral.
Cutting is carried out on pipe products, nuts, bolts, which are used in, for example, water pipes and various parts of equipment. If you are installing a pipeline using products without threaded connections, you need to learn how to cut pipe threads.
According to GOST, it is characterized by the following indicators:
- step - the distance between the bases or vertices of adjacent curls;
- depth - the distance from the base to the top;
- profile - a cross-sectional view of a coil located transversely;
- profile angle - formed by the lateral parts of the turns that intersect;
- internal/central/external diameter – the distance between the bases of the opposite sides/base and the top of the opposite side/points of 2 threaded sides located in opposite areas.
Types of cutting
External threading on bolt, rod and screw elements is created using dies and can:
- have a prism shape;
- have a circle shape;
- be retractable;
- be monolithic.
Prism-shaped cuttings have 2 identical parts, fixed in the die in the form of a frame with handles. On the 2 outer sections there are recesses intended for clamping protrusions.
Sliding dies are placed in the die so that the numbers on the die elements are placed on the opposite side of the numbers on the frame. Fixation is carried out with a special screw. A metal plate block is placed between the die and the stop screw to prevent deformation.
The circle-shaped die is fixed in the collar holder with 2 or 4 stop screws. Using a sliding die, it is possible to manually create a thread on a product, even if there are small deviations in the rod radius.
How to cut threads on the inside of a pipe? This is done using pipe thread taps inserted into the crank part. The tap has a tapping part designed to create threads on the pipe; calibration, through which it is possible to calibrate and cut a hole; a shank with a square-shaped head that allows you to hold the tap in the crank part.
Basic thread positions
When connecting gas pipes to a water supply, cylindrical pipe threads are rolled or cut. The end parts of the pipes are combined with special elements. The last 2 curls of the cylindrical cut are called runaway. The run-out allows you to fix the coupling element on the pipe product. This ensures the sealing of the connection with the seal.
To disconnect connected heating pipes, for example, without cutting, you need to use a squeegee. It contains a lock nut, a coupling element, and a long thread. It has such a length that it is possible to easily screw on the coupling part, the locknut.
In order to save material, gas supply and other complexes use products with thin walls. They are knurled. The thickness of the walls should be greater than when creating threads on a water pipe.
Pipe clamps
On small-sized products, external threads are created with your own hands using pipe clamps. The product is placed in a clamping tool, and the end section is cleaned of scale. After this, the area that is being cut is lubricated with drying oil or sulfofresol.
They put a special object on the pipe with their own hands - a clamp, it has special dies. Using a mallet, lightly hit the washers on the handle so that the direction dies move closer to the pipe. Next, they are secured with stopper bolts. The cutting dies are installed, while resting on the washer mark.
Then the tool is rotated, simultaneously pressing on it.
In the body part of the die, on one side there are 4 holes for the cutting die, on the second - 3 holes for the direction die. The dies are moved away, and the washers are brought closer to each other. They are fixed with ring clamps on the body. In the planes that are adjacent to the body, there are recesses of washers in the shape of a spiral.
They contain pin components. If you turn the washer, the pin components will slide along the recesses, the dies will begin to approach each other (during a left turn) and move away (during a right turn). When they occupy the optimal position, the washer is fixed using the clamp bolts.
Dies are produced, in accordance with GOST, with 2 sets of special dies: for cutting on products with a radius of 0.75-1 cm and 1.25-2.5 cm.
The dies use radial single-sided/double-sided dies. One set contains four items. Each of them is marked with dimensional data and an identification number (from one to four). Special numbers are available for any hole on the body of the screw. The product contains replaceable bushings for any diameter. They are located in the guide flange element and are fixed with a screw part. It is attached to the body part.
Pipe clamps provide the opportunity to obtain clean threads and also make the product stronger. The downside is that they need to be carefully looked after. In addition, the clamps weigh a lot.
If a special tool is used to cut threads on pipes, and the thread has a diameter of 5 cm, it is necessary to move the direction dies by rotating them one hundred and eighty degrees, that is, towards the inside of the die with the shorter section.
Klupp Mayevsky
How to properly cut threads on a pipe? For such a procedure, Mayevsky's clamp is often used. It has split dies containing a couple of elements. Any set of dies is designed for a certain pipe radius. The dies, according to the number indicated on them, are placed in the housing connector with screw elements according to the marks contained on the product. A stop cover is placed on them, which is secured with screw elements.
Mayevsky's clumps are structurally simple, easy to care for, and weigh little. In addition, the dies can be quickly replaced.
Ratchet clamps
How to cut threads on a pipe, besides the above methods? It is possible to use a ratchet clamp. It is designed to create threads with a diameter of 2.5/2/1.5 cm on products, for example, stainless steel. A head is fixed in its body part, which is equipped with replaceable dies. There is a ratchet wheel at the bottom. When turned, it ensures rotation of the die head.
There are 2 ratchets in the clamp housing. The die head rotates using the handle. Cutting is carried out using a rolling motion, it is performed by the handle when the wheel is running. Upon completion of cutting, a ratchet is launched, clinging to the teeth and driving the die-circle. Using a die, it is possible to make carvings in those areas in which the use of ordinary tools is ineffective. It is especially useful during repairs.
To create a thread on a product, it is fixed in a clamping device so that the protrusion being processed is small. The longitudinal protrusion may be subject to deflection when cutting. The end part of the treated area should be placed at an angle of ninety degrees relative to the pipe axis.
The tool is mounted on the product with directional rings/dies. The cutting dies should extend a couple of turns onto the tubular product. The pipe threads are lubricated with oil fluid. This is required to cool and clean the dies. Before you begin the procedure, check that you have installed the die correctly.
Its number must be the same as the number of the housing connector.
To cut, the tool is twisted and moved to the front. At the end of processing the product, the clamps are disassembled, cleaned of dirt and metal filings, and lubricated with mineral lubricant. Every week you need to clean the tool from dried grease.
Source: https://oxmetall.ru/rezba/tsilindricheskaya-trubnuya
How to properly cut a thread on a pipe with a die?
Currently, plastic or metal pipes are mainly used for laying water supply systems.
Plastic products are connected to each other, as a rule, by welding (a special welding machine is used for these purposes).
Metal pipes are joined with threaded fittings, in this case the connection is as strong as possible.
articles:
Not many people have thought about how to connect the water supply to a private house.
It consists of:
- pipes,
- valves,
- valves
- taps and other components.
All this is assembled into a single system using threaded connections.
To ensure that the process of replacing an old part with a new one does not take much time, there is a thread.
Sometimes you have to deal with cases when you yourself have to change a worn-out element (for example, a pipe), but there are no grooves on it.
What to do in this case?
The way out of this situation is very simple - cut the thread with your own hands. The ideal option is when you have the opportunity to use a lathe.
But not every home craftsman has such equipment.
It is expensive, and in order to use it you need to have certain experience and skills.
Do you know the cost of installing radiators in an apartment? The approximate cost of aluminum, bimetallic and cast iron radiators for heating living space is indicated in a useful article.
Find out what can be glued with silicone sealant on this page.
If you need to equip a pipe with threads , for example, to connect a membrane tank for water supply (written here), you can use one of two types of devices designed for cutting grooves:
- thread cutting table,
- pipe wrench.
This tool is used to cut threads in water and sewer pipes (read why a water seal is needed here), which are used in the utility networks of multi-storey buildings and private buildings.
Note! If you do not have any experience in this matter, then working with a lecher will be very difficult for you. Since even the slightest misalignment of the tool will invariably lead to the formation of a defect.
In this case, it is best to use a wrench; the cutting process with its help is simplified by the presence in the design of such an important part as a guide.
In order not to spoil the water pipe , to acquire a certain skill, practice on an unnecessary piece of a hollow object.
Now let's try to refresh our memory about what the thread cutting process is:
- when applying grooves to pipes , a helical surface is formed on the outside of the hollow object;
- the helical plane plays the role of a connecting element, which rotates steadily around the axis of the fitting;
- The thread pitch corresponds to one full turn.
In order for the junction of water pipes to be waterproof, durable, and the unit to withstand high pressure in the system, it is necessary to cut the threads so that the pitch exactly matches the pitch of the joining parts.
Tools used for these purposes
Before you begin, you need to make sure that you have all the necessary equipment at hand.
Pipe threading kits are sold in stores . These can be dies of the required diameter or a set of clamps (this option is more practical).
First of all, it is necessary to thoroughly clean the pipe from rust and remnants of old paint.
from the end surface of the pipe .
It is extremely important to know! The tool for the job must be of high quality.
Do you know why a casing pipe is needed for a well? A useful article describes the rules for drilling on a personal plot.
Read how to push through an air lock in a heating system here.
On the page: http://ru-canalizator.com/santehnika/s-oborudovanie/kosvennye.html it is written about making indirect heating boilers from stainless steel with your own hands.
There is one more point to consider:
- do not forget to purchase lubricant for more productive operation of the cutting device and removal of chips.
List of tools without which you cannot complete this job:
- pencil or piece of chalk,
- roulette,
- calipers.
The pipeline must be installed according to pre-prepared drawings. The first thing to do is prepare the pipes.
Their length must correspond to the parameters indicated on the heating and water supply diagram of a private house (written here).
A tape measure and a pencil are necessary for marking.
Without a caliper, you will not be able to correctly determine the cross-section of pipes and accurately select the tool.
It is necessary to mark the pipes extremely, carefully and, as much as possible, carefully.
If you make even the slightest error in measurements, the device will turn out incorrect, and as a result you will have to make a new design.
Grinder or hacksaw for metal.
These devices cut the pipes according to the markings made earlier.
Important condition! The cut in relation to the pipe walls should be strictly perpendicular. Otherwise, the threaded connection, for example, when connecting a circulation pump to a heating system, will not be sealed.
A device for clamping and holding an object during processing - a vice. With their help, you can cut the pipe as smoothly as possible.
Lubricant material (this can be machine oil).
By cutting a hollow object by hand, you can make your work much easier. To do this, you need to lubricate the end of the pipe and the tool with a special compound.
You will need glasses to protect your eyes.
When cutting grooves, metal shavings are formed. If it gets into your eyes, it can cause severe damage.
A tool designed directly for applying threads to pipes:
- set of dies,
- Klupp,
- tap.
In order not to make a mistake in choosing the right device, you need to take the type of thread as a basis and rely on the preferences of the master.
External threads are applied using a die, and internal threads are applied using a tap.
How to make a clump correctly
The process should occur according to the following structural diagram.
- You need to choose a leech of a suitable cross-section . To accurately select equipment, you must use a caliper.
- The prepared section of the pipe and the inner surface of the tray must be lubricated with machine oil.
- A die is inserted into a metal pipe; a holder is used for this (it is included in the kit for cutting grooves on pipes).
- If you are performing initial pipeline assembly or you decide to install a tap for a drinking water filter (written here), then the hollow object should be fixed in a vice - this will make the work easier.
When reconstructing a water main, threading is done directly on the installed pipe.
- After all the preparatory measures have been completed, it is necessary to insert a tap of the appropriate diameter into the pipe opening, and then rotate its base clockwise.
For this purpose, use a wrench, which is included in the tool kit.
Chips form on the grooves and must be removed.
How?
It is necessary to make several turns around the pipe, and then move the device 90 degrees in the opposite direction.
At the end of the work, the remaining oil should be wiped off with a clean rag.
Grooving with a die
This type of threading device is:
- round configuration . In order to cut threads into pipes of various sections, use dies of different sizes;
- sliding . Such a part is used for cutting grooves on hollow objects of different diameters. The sliding die is operated using a special holder.
This tool model is used more often. The reason is the low cost of the product.
Before starting work using a die (die), it is necessary to prepare the pipe using the method described above.
Only after this should you proceed to the procedure according to this scheme:
- Select a device of the appropriate diameter (for this use a caliper).
- Then we lubricate the surface of the product and the inside of the die with any lubricant.
- Next step – securely secure the lever in a vice.
If you do not use a holder, the threads will not be straight, and this may cause leaks to form at the mating points.
- Turn the die holder in the desired direction.
After making a few turns, you need to remove the chips.
To do this, turn the device in the opposite direction.
- At the end of the work , the tool and threads must be cleaned of grease.
How to cut trapezoidal threads on a lathe?
At the first stage, they use roughing tools (they clearly cut through the pipe).
But with their help you will not be able to achieve maximum carving accuracy. The final cutting is done using a finishing blade.
Cutting the internal thread
What do I need to do.
- Prepare the opening thoroughly.
The hole must be clean, free of foreign coatings and deposits.Then, it must be lubricated.
- Select a tap by diameter.
- Secure the tool in the hole.
Remember that the vertical position of the threading device must be strictly observed.
The tap must be rotated clockwise.
It is important to know ! The manufacturer must apply markings to each die.
It specifies all the sizes of the grooves that can be cut using this tool.
Before you start work (watch a video on how to lay sewer pipes in different ways here), you should carefully study this data.
If you need to cut threads on stainless steel pipe , you will have to work a little more.
Since stainless steel is a very hard material, the task becomes significantly more complicated.
In this case, you will have to buy a die that matches the steel grade.
Markers with branding - P9 are suitable for this purpose..
Important point! If the die is selected incorrectly, then, in the end, you may be left not only without a thread, but also without a tool.
Basic reasons for marriage
No one is immune from the fact that the result of your work will be marriage.
What could be the reason for its occurrence?
- Mismatch of the cross-section of the holes or rods of the cut grooves.
- Using a tool of poor quality (blunt or incorrectly aligned).
- Do not use lubricants during operation.
- Lack of professionalism.
There is nothing difficult about cutting a thread on a pipe yourself.
There are no tricks to this.
The main thing is to have a special tool at your disposal.
Perform all actions carefully and slowly. And one more thing you shouldn’t forget:
- In order for you to succeed, you need to have desire, and skill is an acquired skill.
Any homework can be done on your own , the main thing is to find the right approach to it. This way you can save money from the family budget.
Master class from a home craftsman who took up threading a pipe for the first time - watch the video.
Source: https://varimtutru.com/kak-pravilno-narezat-rezbu-na-trube-plashkoy/
Tapping a thread on a pipe
[How to cut a thread] is a pressing question, because... this is the main method for connecting structural elements.
This can be done manually using a special device.
External and internal cutting of the part is separated, thanks to which the thread can be installed in holes of different types.
The cutting method depends on the type of material you will be working with.
You will find the features of the process, as well as a description of the tools that are needed for this, in the article, and the video will help you cope with the task.
Tapping tap
A tap is a metalworking and turning cutting device made in the form of a rod with a cutting element mounted on it.
The cutter is used to create internal threads in various metal parts, pipes, and it can also be used to restore previously damaged threads.
The cutter has a working part and a tail part. The working part includes two sections: for cutting and for calibration.
The cutting section is usually cone-shaped and is responsible for direct thread cutting.
In this area, cutting teeth are also installed, which cover the area along the entire circumference. The calibration section is responsible for the final formation of the part.
It looks like a cylinder equipped with teeth, and continues as a cutting area.
It is longer, and its working element is divided by grooves needed to create cutters and remove chips.
The number of grooves depends on the size of the tap with the clamp - in devices not exceeding 22 mm, there are usually three of them. There are also special taps that do not have grooves.
In those devices where they are, the grooves can be straight or helical.
The back of the tap has a cylindrical shape, at the end there is a square, which is necessary for the possibility of fixing to the fastening tool.
This part of the tap is responsible for attaching the device to the hand holder or machine chuck.
Taps with clamps come in two types: manual or machine. Hand-held devices attach to hand-held holders and are designed to create internal threads.
Machine tools are installed on chuck holders of lathes.
Before you learn how to cut a thread with a tap, you need to decide on its type. The threads that can be made may vary depending on the type of device.
IMPORTANT TO KNOW: We sharpen a metal drill correctly
The most common form of thread is metric - it is made using a metric tool.
To create threads on the inside of a water pipe, as well as in a heating pipe, specialized pipe taps are used; they can also be used to make reinforced threads in metal parts, and not just in heating elements.
To create a tapered or inch thread, you need to use a special inch tap, which allows you to make threads of the smallest size.
Most often you can find durable steel devices with a clamp - they are the most efficient, strong and durable.
In addition to the type of thread, taps differ in design: they can be single or complete.
The latter are used to create threads in several passes. Typically, the kit includes two taps, one of which is called finishing, and the second is called rough.
In some cases, a tap is added here for medium processing. The number of parts in the kit is always indicated on the back, on the tail part.
The complete taps are not the same; they have different tooth shapes: the rough tap has the shape of a trapezoidal tooth, the middle tap has a triangular shape with a rounded apex, and the finishing tap has a standard triangle with a sharp tip.
Threading involves creating a protrusion in a hole, and the protrusion line should have a helical shape.
The protrusion near the wall in the hole must meet the specified parameters in order for the thread to be used: it must have the correct pitch, lifting angle, outer and inner diameter, etc.
Another important parameter is the depth, which is determined based on the diameter of the threads inside and outside the pipe.
There may be several options for how to cut a thread correctly.
The direction of the thread in the pipe can be different, depending on the need: it can be directed to the right, in which case the protrusion develops clockwise, or it can be left-directed, in which case the protrusion will follow counterclockwise.
There are two possible profile shapes: rectangular or triangular, as well as special additional shapes, but they are used mainly in production, and almost never at home.
Tap selection and cutting
A tap is selected depending on the thread that is needed, as well as its purpose (the thread may differ in profile shape, thread pitch, tolerances).
IMPORTANT TO KNOW: Types of wire bending machines
To select a tap, there is a table that shows the accuracy classes - in accordance with them, you need to choose what type of tap to purchase - a set or a single tool.
An important factor to consider when choosing a tap is the required accuracy of profile cutting.
Different tools have different finishes on the cutting element, and this also needs to be taken into account.
The metal you will be working with will directly affect the tap you will need for it.
On aluminum, a sharpening angle of at least 25 degrees will be required, on cast iron and copper up to 5 degrees will be enough, and on steel – up to 10 degrees.
For the manufacture of the tap itself, ordinary or high-strength steel is most often used. When choosing, you need to focus on the diameter of the hole in which the thread will be made.
Before creating threads in aluminum, cast iron or other metal parts, you need to make a hole. It can be through or blind, depending on the need.
The hole can have any diameter, it is only important that it be smaller than the future cutting. It is best to choose a drill bit for the hole based on the thread size.
There is a special table that shows the recommended drill diameter in accordance with the thread size; it is recommended that you familiarize yourself with it before starting work.
If you need to make a large wall thread on cast iron or aluminum, then you should choose the diameter for the hole by multiplying the thread diameter by 0.8, so you will get a value that will be closest to the required size.
Creating a hole for an internal thread is not done manually, but using a special drilling machine or electric drill.
If using a drill, the workpiece must first be clamped in a vice so that the drilling location is exactly where it is needed.
When drilling, the drill must be positioned strictly vertically and not deviate from the specified plane.
To make it easier to work with a tap, you can chamfer the top edge - then the device will fit easier.
IMPORTANT TO KNOW: How is sheet metal bending carried out?
This can be done using a drill with a larger diameter or a file. After finishing the work, the hole must be cleared of chips.
This must be done especially carefully in a blind hole, otherwise cutting will not work well.
Before drilling, the part you will be working with must be firmly secured with a vice, with the chamfer on top, and the axis of the hole you made must be perpendicular to the table.
The tap must be fixed into the socket of the driver, and then inserted into the chamfer of the workpiece hole. The device is always inserted vertically.
After this, you need to press the tap firmly against the workpiece (preferably with both hands) and begin to rotate it clockwise.
Sudden movements or stops should not be allowed: the device must be rotated slowly and evenly, but at the same time work with pressure.
You need to work with the tap in the following sequence: first two turns forward, then half a turn back and then forward again. This method involves processing the entire hole in the pipe.
The tap needs to be cooled from time to time while cutting.
Different cooling methods are used for different metals: kerosene will be effective for aluminum, turpentine will be effective for copper, a special emulsion will be effective for other metals, and when cutting in cast iron, cooling the device is not required.
For internal threading, it is best to use tap sets.
The work is as follows: first you need to make a rough thread, then use a medium tap, which is passed through the hole, and then the final cut is formed using a finishing tap.
This sequence is optimal for the best processing quality, so it is recommended not to skip any of the three devices, otherwise the quality of the thread in the pipe will be noticeably worse.
You can see all the stages of the cutting process in the video - there is nothing complicated in this process, the most important thing is to choose the right diameter and follow the sequence of work, and also remember how to work with this or that type of metal.
In this case, you will receive high-quality threads in the pipe, which can be used to connect any parts.
Source: https://rezhemmetall.ru/kak-narezat-rezbu-metchikom-na-trube.html
How to cut a thread with a tap
We cut the thread with a tap. The most basic and common option for fastening parts is a threaded connection. It would seem that making it yourself would not be difficult. In fact, correct cutting of a thread with a tap requires compliance with many rules, otherwise a high-quality connection will not be possible in the future, or even the thread will not succeed at all or the tool used will become unusable. How to cut a thread with a tap yourself.
Tool selection
Poor quality tools mean poor quality work. Using old, dull or rusty taps or dies is fraught with the risk of them breaking during operation and poor threading on the part. In addition to tools that have been unusable for a long time, you should also avoid those that were unsuitable from the very beginning. These include all cheap options of unknown origin.
In addition to quality, their size is also important, namely the ratio of the sizes of the drill used and the hole for it. You can calculate the necessary parameters using the formula, but to facilitate this process, examples with exact ratios are given:
- metric thread M2 – drill (tap) diameter 1.6 mm;
- m.r. M2.5 – d.s. 2.2 mm;
- m.r. M3 – d.s. 2.5 mm;
- m.r. M4 – d.s. 3.3 mm;
- m.r. M5 – d.s. 4.2 mm;
- m.r. M6 – d.s. 5 mm;
- m.r. M8 – d.s. 6.7 mm;
- m.r. M10 – d.s. 8.3 mm.
Parts lubrication
This point is very important, because thanks to it the tool used will last many times longer. In addition, it reduces the likelihood of drill breakage inside the hole and reduces the temperature of the heated edges of the tap. But when choosing a lubricant, you must take into account the material of the parts on which the thread is applied:
- steel, brass – linseed oil;
- aluminum - kerosene;
- copper - turpentine;
- bronze, cast iron - without the use of coolant (cutting fluid).
It is not recommended to use mineral or machine oils as a lubricant. Their composition does not allow the surface of the tap or die to glide smoothly, so the thread will be rough.
How to Tap a Thread: Internal Threading
The main nuances have already been discussed; now you can go directly to how to cut a thread with a tap or die. The process looks like this step by step:
We clamp the workpiece in a vice.
We drill a hole for further cutting of the internal thread.
Using a drill whose diameter is several millimeters larger than the planned thread, we apply a chamfer to the edge of the hole. It is necessary for easier insertion of the tap, as well as to facilitate the process of screwing the screw into the finished product.
We insert a rough tap into the driver (a device for fastening taps and dies).
Apply lubricant to the cutting part.
Insert the tap into the hole and make three turns.
After the first three revolutions, we make one revolution in the opposite direction. Thus, we break the chips resulting from the cutting process and they will not interfere with the high-quality and even application of the thread.
If the hole in the part is through, it is necessary to make sure that the front part of the tap comes out completely from the back side. Without doing this, we risk getting an unfinished thread.
Breakage of the cutting part of the tap in a blind hole
If the end of the broken part is completely “recessed” in the hole, it will be very difficult to get it out. But if you have some patience, it’s still possible to do this. You will need paraffin, an oblong and thin wooden stick, and nitric acid. Lubricate the workpiece with paraffin (protect it from acid). We moisten the end of the stick with acid, insert it into the hole and lubricate the cutting edges of the metric. How to cut a thread with a tap
It is necessary to continue the procedure until the edges begin to melt. After this, the fragment is either knocked out with a hammer from the back of the part, or picked out with tweezers.
How to cut threads with a estimator: cutting external threads
Having taken the necessary part, we clamp it in a vice. We make a small chamfer on one side with a file, lubricate this side with oil, kerosene or turpentine (depending on the material).
We insert and fix the die into the die holder. We place the die to the desired end of the pipe and slowly rotate it in the direction we need with one hand, with the other hand we make sure to press the top of the die to the pipe.
When the die is firmly seated on the pipe, check that it is perpendicular to the pipe, grab the die holder with both hands and make 3-4 turns forward, and then half a turn back.
When cutting external threads, there is one caveat: during the last turns, do not rotate backwards, this will allow the nut to be firmly fixed on the pipe.
Please note that freshly cut threads should not be touched with bare hands; they may have very sharp burrs and there is a high risk of cutting.
Noteworthy information : Threading die , How to attach an anchor bolt
[tab:]
Source: https://stroitelinfo.ru/materialy/kak-narezat-rezbu-metchikom
How to cut threads correctly with a clamp
Even many experienced locksmiths have no idea what a clamp is, not to mention ordinary people. And this tool can help you out a lot when laying a home pipeline. We will talk about how he can do this in this article.
Pipe clamp 1-1 2-1/4-3/8-3/4 with ratchet and in a plastic container
General provisions
Let's start, perhaps, with the function performed by the clamp - thread cutting. You can rightly argue that the appearance of plastic pipes in everyday life has made the use of threaded connections unclaimed. Thus, polyethylene products are connected with special fittings for sewer pipes, while polypropylene products are simply welded.
Photos of plastic pipe connections using fittings
But things are not so simple when it comes to reliability. To better understand what we are talking about, let's take a look at the disadvantages of polyethylene and polypropylene:
Disadvantages of using plastic pipes
- Limitation of temperature conditions . For polypropylene the limit is 95 °C, and for polyethylene – 40 °C. In our harsh winters, there are situations when the boiler room has to supply water that exceeds technical standards, which will undoubtedly lead to an accident. So it is very risky to use this type of pipe for a heating system.
- Weak resistance to mechanical stress . This immediately eliminates the possibility of laying a plastic water pipeline under the roadway, since it will simply be crushed over time. And in places open to contact, you will also have to be careful, remembering the vulnerability of this material.
Polypropylene pipe cracked under load
But metal is not afraid of either high temperatures or excessive mechanical loads. But even with him in the matter of connection, not everything is so simple:
Types of steel pipe connections
Advice: it is recommended to use exclusively galvanized products to prevent destructive corrosion processes and rust from entering the pipeline.
Galvanized pipes for water supply system
Type of connection | Advantages | Flaws |
Welding | Completely sealed | Deterioration of the zinc layer, as a result of which the pipeline becomes vulnerable to corrosion processes |
Thread | Possibility of dismantling | The need to use additional seals to achieve optimal sealing |
Using tow to eliminate a possible leak is not as dangerous as damaging the coating that protects against rust. In addition, not everyone knows how to use a welding machine with their own hands. Also important is the possibility of maintenance, which is very problematic with a solid line. So the threaded connection wins by a clear margin.
Manual pipe threading die with convenient holder
Of course, a lathe is ideal for cutting threads, but there are many problems associated with its use, the most important of which is its absence. So what remains is a die or die.
Definition
Professional set of clamps for pipe work
If the die has the form of a small cylinder made of high-quality tool steel with cutters and grooves for chips located inside, and holes for fixing holders on the outside, then a die is just cutters with a holder mechanism that simplifies the work.
Thus, despite the fact that the price of the die may be higher than the die, as a result you still save. Since in it expensive material is used only for the working consumable part, and the die consists entirely of it and is thrown away after it is used up.
Kinds
A set of pipe clamps and additional plumbing tools
Clupp name | Description |
Simple manual | A ring with clamps for cutters and handles, which looks very similar to a regular die |
Manual with ratchet | A ratchet has been added to the ring, allowing you to use the tool with one hand. |
Electric | In this case, all the instructions boil down to fixing the pipe in the appropriate groove, the electric drive will do the rest for you |
Advice: when choosing between a simple tool and one equipped with a ratchet, it is recommended to choose the first one, as it is much more reliable and practical.
Model KTT-1 4-1-1 2 2 with ratchet
Terms of use
Cutting threads on a pipe with a clamp at home
Now let's figure out how to use a pipe clamp.
To do this, it will be enough to follow a few rules:
- Before cutting a thread on a pipe with a clamp, it must be rolled by turning with a file, crimping with a gas wrench, or by any other available method.
- Lubricate the cutting area with grease - this will improve the quality of the cut threads and extend the service life of the cutters themselves.
- When purchasing new cutters, check with the manufacturer of the holder. Otherwise, they simply may not fit tightly into the grooves.
- When working on the pipe end of an existing pipeline, hold it with a gas wrench so as not to tear it off.
Conclusion
Despite the fact that today plastic sewer pipes are very popular due to their low cost and ease of processing, metal ones remain more practical and reliable. The best connection for them is a threaded one, which in turn is most convenient to cut with a screw. The types and features of such a tool are described above.
Pipe cutting die equipped with an electric drive
This article will introduce you to additional materials. Use the most convenient tools for working with plumbing!
Source: http://ooo-asteko.ru/kak-pravilno-narezat-rezbu-kluppom/
How to cut threads on a pipe yourself?
To cut threads on various pipes, the performer must have an understanding of the features of the process and have a certain skill. In our material we will explain to you how to freely cut threads at home.
Having mastered this process, you will be able to repair any household appliances, plumbing, heating networks - in short, any systems containing threaded connections on pipes.
Thread cutting methods
The technology of the pipe threading process includes various methods:
- the use of special threaded dies and cutters;
- knurling using flat or round dies;
- use of threading heads, taps or dies;
- milling with special cutters.
Accordingly, the thread cutting process requires the presence of special tools and devices. In this material we will step by step consider the method of cutting threads with a die - a special thread-cutting kit.
Tool composition
A die is a special device for cutting threads, equipped with several sets of cutting radial dies. They have different diameters, suitable for a particular sewer or water pipe.
In addition to the clamp you will need:
- a set of taps for cutting internal threads;
- gas wrench or vice for fixing the pipe;
- machine oil or any other;
- grinding machine for metal processing with a cutting disc.
Note! When working with a grinder, you need to protect your eyes and hands with special glasses and gloves.
Sequence of operations when cutting external threads
First you need to make sure that the pipe is in good condition and will not break when threading. If the pipe is painted, then it must be stripped of the paint layer.
We mark the place of the cut on the pipe and use a grinder to cut off the unnecessary piece of pipe perpendicularly, having previously fixed it with a vice or a gas wrench.
A chamfer is cut off at the edge of the pipe - this will simplify the process of screwing on the die. It is better to lubricate the place of the future thread and the teeth of the die with oil, or at least regular lard, for easy sliding. Next, we proceed directly to cutting the thread.
Usually two dies are used - a through dies, or a roughing one, the cutters of which only form the profile and a finishing one, cutting the thread directly. This, firstly, facilitates the cutting process itself, and secondly, reduces wear on the tool itself. We press the die holder with the pass-through die attached to it with force against the pipe so that an engagement is created. Then rotate the holder clockwise.
After making several turns, usually five turns, we change the direction of rotation to the opposite, turn half a turn back to clear the threaded groove from chips. The chips will break off and it will be easier to cut, then turn clockwise again. It will be correct to cut the first thread with a guide bushing so that the thread does not become skewed. The bushing must have an internal diameter that matches the external diameter of the thread being cut.
A die holder can be used to secure it. This improvement will ensure that the threads are aligned with the pipe. Next, we begin to work with the finishing die, not forgetting to first lubricate its teeth. For greater force, you can lengthen the handle of the holder. It is very important not to try to do all the work in one pass. You need to move half a turn, gradually. Otherwise, you can bend the pipe and break the die.
You should not cut threads longer than 1 cm: this is the length of the threads of most elements of household water supply networks. At the end of the process, the freshly cut thread must be cleaned of chips and wiped of oil.
Internal thread cutting
This thread is cut with a tap. To select it, you need to know the exact size of the thread hole. If it is blind, then its length should be several millimeters longer than the required thread.
The hole is pre-drilled with a drill to remove the excess layer of metal and facilitate threading. It is better to select the required diameter using reference tables. But, you can make a rough calculation: it should be equal to the difference between the thread diameter and its pitch.
Then the cutting itself is performed directly in two passes: first, about 70% of the chips are removed with a rough tap, then with a finishing tap, the remaining 30%. The rotation of the taps is carried out clockwise using a “wrench” - a special tool for holding them.
Before operation, the taps must be lubricated with machine oil.
In this way, you can independently obtain a high-quality threaded fitting.
Source: https://tepliysezon.com/kak-samomu-narezat-rezbu-na-trube/