Removing rivets
TO category:
Riveting
Removing rivets
When repairing machines, equipment, household items: kettles, locks, shovels and many others, you often have to separate parts and remove old rivets. In order not to spoil the parts, this operation must be performed using special tools.
They cut off the semicircular head of the rivet with a special chisel, called a jamb, and knock it out of the hole of the parts using a beard. They do it this way:
From one surface of the part, where it is more convenient, the head of the rivet is cut off with a hammer on the jamb. Then support is installed on the opposite side of the parts. Moreover, the support should be taken such that its mass is greater than the mass of the hammer, and the diameter of the tool hole is slightly larger than the diameter of the rivet head. The head of the rivet should fit into the support hole. Place the bit in the center of the rod (in the place where the head was cut off) and knock out the rivet with hammer blows.
Rice. 1. Square. Round head rivet connection details
Rice. 2. Chisel for removing rivet heads (jamb)
If cutting off the head of the rivet is difficult or inconvenient, and the part can be damaged, proceed as follows. The head is sawed off a little, a core mark is placed in its center and the rivet is drilled out. The diameter of the drill should be slightly smaller than the diameter of the rod. If the rivet is not removed during the drilling process, it is finally knocked out with a beard.
Rivets with countersunk heads can only be removed by drilling. If the countersunk head of the rivet is broken, then the rivet can be knocked out with a beard.
The rivet is an excellent and durable type of fastener. But unlike bolts, nuts, studs and screws, it cannot be removed without causing damage. The bolt can be unscrewed with keys or a screwdriver, after which it can be reused. The broken rivet will have to be thrown away. The question also arises: “How to rivet rivets if you don’t have a riveter in your arsenal?”
The essence of the rivet
The rivet is a disposable fastener. But it is also the cheapest. If the device is being made permanently and does not involve disassembling parts in the future, these parts can be riveted together. They will hold just as firmly as screws, but will be even more secure. The screw may come out over time, but the rivet itself will not come apart, since it is impossible to rivet it without the help of special tools.
Rivets in construction and mechanical engineering
There are many. Some have the form of a single part - a bushing, which is inserted into the hole and, using a special riveter, the edges of the bushing are expanded on the other side of the parts being connected and pressed (flatten). Such rivets are the most common, cheap and reliable. They are used mainly in construction and mechanical engineering. How to rivet construction types of rivets?
Removing a construction rivet
It is difficult to call this action dismantling as such. This is deletion. To remove the rivet, you will need the regular rivet gun that was used to install it. But since you don’t have one at hand, it’s worth figuring out how to rivet a rivet without a riveter.
You can try to remove rivets in which the head or bent part protrudes above the plane of the riveted parts with a sharp chisel and hammer:
- Place the cutting part of the chisel exactly under the head (or bent part).
- Hit the chisel with a hammer. Some large rivets may take a few hits to break off.
- Once the head (or bent part) is torn off, all that remains is to remove the rivet from the hole. This can be done by pushing it out with a nail or other thin object (for example, a screwdriver).
But more often you cannot get to the caps and curved parts, since they are, as it were, in the body of the parts being fastened. At the factory, special grooves are drilled for the caps and expanding parts in the parts, and then the rivets fit into the metal like a glove. How to rivet rivets in such a “tricky” case?
Here a screwdriver (or drill) with a metal drill selected for the diameter of the rivet will come to the rescue. Proceed as follows:
- Using a core, make a notch on the head of the rivet so that the drill does not wander, although some are accustomed to doing without serifs.
- Place the screwdriver bit on the head and drill out the inside of the rivet.
- When the drill goes through, the remains of the head and widened part fall out on their own.
Rivets on clothes
But rivets are also used in the manufacture of various types of clothing. Their use began in the 19th century, when, while sewing pants made of rough canvas, which will later be called jeans, one of the craftsmen noticed that if the seam is riveted at the beginning, it will definitely not come apart or tear.
Here rivets are used, for which the name “buttons” is more appropriate. Unlike ordinary ones, they consist of two parts - internal and external. Everything is held together by the fact that the head of one element fits into the cavity of another. Then, under pressure from the riveter, the head of the internal element is flattened (expanded) inside the cavity of the outer element, and such a “super button” cannot be broken, no matter how hard you try. Quicker the fabric will tear. How to rivet these types of rivets correctly?
Removing rivets from clothing
This is done in two ways. One - with the help of side cutters, the other - with a knife and a pair of pliers. The choice of methods depends on what type of rivet you have - alpha (internal) or beta (external). The corners and edges of the stitching are mostly riveted with alpha varieties, otherwise known as grommets. Beta is used in cases of buttons used to fasten clothing. One part there is alpha, and beta is riveted onto it. Despite the fact that such rivets hold the material perfectly, they are afraid of mechanical stress.
How to rivet alpha rivets using a knife and two pliers?
It's done.
How to rivet a beta rivet on clothes? Everything is even simpler here. The procedure is as follows:
Many have seen this device in stores selling tools - but not everyone knows how to use it. Those who have never held a blind riveter in their hands simply will not be able to appreciate the convenience and versatility of its use.
Rivet joints have been and remain a universal and inexpensive way to join various parts. In shipbuilding and aircraft construction, this is generally the only way to attach the skin to the frame.
A classic riveting looks like this:
This is exactly how they riveted the hull of the Titanic and the handle to your frying pan.
IMPORTANT! The rivet connection is non-separable. To separate the parts it is necessary mechanically break (drill, cut) the rivet.
Modern technologies We also touched on this ancient method. In everyday life, few people use a hammer and a crimping attachment. There are semi-automatic tools that allow you to rivet parts to each other almost with one hand. True, the rivets look a little different.
How does a manual riveter work?
To understand the process, you need to see the rivet in action. The diagram shows its main elements:
The rivet sleeve is placed in the prepared hole. The tool is put on the core and rests against the shoulder of the rivet. The fixed rod is pulled out of the sleeve, riveting its upper part.
When riveting is completed and the head of the core is firmly seated in the riveted sleeve, the core comes off. The riveted materials are connected only by a sleeve.
IMPORTANT! The material describes a mechanical riveter. There are hydraulic, pneumatic and electric devices. However, they are not used in everyday life.
We will also consider the operating principle of the tool itself and its structure in the diagram.
- the head (1) is put on the core of the rivet installed in the hole;
- the body (2) performs the functions of the lower handle and thrust frame;
- the upper handle (3), resting on the frame with the help of an axis (9), is a power lever;
- when the handles are compressed, the working sleeve (4) compresses the collet cams (5), tightly fixing the rivet rod;
- continuing to move, the collet mechanism pulls the rod out of the rivet sleeve, forming a riveted ring;
- when opening the handles, the conical bushing (6) under the action of the spring (7) opens the cams, allowing the collet mechanism to take its original lower position;
- the cover (8) is a stop for the spring and is removed for servicing the collet mechanism;
- For the convenience of the operator, interchangeable heads (10) for different rivet diameters are stored in the housing.
A rivet is a disposable fastener designed to fasten 2 or more parts. To install this fastener, a riveter is used. How to remove a rivet will have to be based on the availability of available tools, because there is no universal tool. In addition, the selection of metal construction materials is carried out in accordance with the technical characteristics.
Aluminum, copper, steel vary in hardness, in to varying degrees they are subject to diffusion, oxidation rates and other physical and chemical processes. The only method that can be called almost universal is drilling. This process can be carried out in 3 ways, which in most cases depends on how close the fastening metal is to the elements being fastened.
How to remove a blind rivet
The pop rivet is somewhat easier to remove. When dismantling it, it is necessary to remove the ring formed during fastening. If possible, when compressing the material of the structure, insert a metal saw blade, the fastening can be cut off, and the pin can be removed by pulling it out by the rod. If sawing or cutting is not possible, there is always a chance to remove the fastening using the first method - drilling.
The hidden fastening can only be removed by drilling, and the exhaust heads can be knocked off with a hammer if the strength of the material they fasten is greater than that of the fastening itself. Provided that using this method of dismantling, there is no confidence in 100% safety for own hands And appearance material, it is better to refuse it.
Today, the most reliable option for fastening joints is one-piece, and if you have special tools on hand, you don’t have to think about the question of how to rivet a rivet. Next we will tell you exactly how such fasteners are made.
1
What is this fastener? Initially, historically, it was a metal rod, less often a plate. Always with a locking head on one side (a cap that limits the movement of the element in the hole) and a locking head on the other end. It was first used for the manufacture of armor, such as plate and chain mail, as well as for connecting some elements of edged and early firearms. If the embedded head is present initially, then the closing head appears as a result of the process of upsetting (riveting) or with the help of a special tool due to deformation by a pulling rod. It is logical that the upset applies to cast or stamped, all-metal elements, and deformation by a rod is possible only when using hollow (tubular) blind rivets. There are also explosive and cutting options.
Various types of rivets
So, we know that the fasteners we are considering are one-piece, which often ensures high reliability. But the strength of the connection depends primarily on the material, so we will first consider the types of rivets according to this characteristic. Aluminum fasteners are the most common, but copper and brass rods are used in many manufacturing processes, as well as in a number of crafts. All these materials do not have high degree reliability and are suitable only where there are no heavy loads, for fastening decorative parts. Among other things, there are steel rivets, including stainless steel, they provide sufficient strong connection and are even suitable for the assembly of load-bearing structures and mechanical engineering.
Very important during installation metal parts use rivets made of the same material as the elements being connected.
2
Before using rivets, you need to know how to rivet certain parts correctly. There are many connection methods, but they are usually divided into 3 types. Durable fasteners are used exclusively where certain loads are present. Sealed, as the name implies, are needed in order to ensure tightness at the joints of sheets or any parts. And finally, tightly sealed ones perform both functions. It should be noted that for the second type, that is, for hermetic rivets, the embedded heads are made reinforced.
Blind rivets
The most common connection method is overlapping, and it is applied not only to parts, but also to parts of complex shapes. This option is also called single-cut. Under the influence of multidirectional loads, for example, when stretching, such a seam can easily deform. A more durable joint is a butt joint, using one or two (on both sides of the seam) overlays, but this option, also called multi-cut, makes the structure heavier and leads to greater consumption of material. Installation of rivets during fastening can be chain or staggered; the second is more reliable, but very labor-intensive.
Mortgage heads come in the most different forms. The most commonly used ones are semicircular and hidden. The former completely cover the hole, like the head of a screw, and for the latter, the channel is flared so that the head, shaped like an inverted cut cone, fits completely into the hole. In the second case, the surface of the part remains smooth, since the riveting occurs flush, and the destruction of such rivets becomes difficult. There are also semi-flush form factors (with a small rounded convex), flat, flat-conical, conical and oval.
3
The most commonly used today are pull-out riveting elements, which are especially convenient if you need to attach a part to a surface the opposite side of which is inaccessible. They are a tube with a flaring at one of the ends (analogous to a mounting head), in the channel of which there passes a rod with a cap at the flat end of the riveting. From the flared side, a large part of the rod is extended, with which the tool clamp engages, for subsequent pulling through the tube. Its straight end is crushed by the head of the rod and forms a closing head.
Rivets for metal
However, it should be taken into account that when two parts are connected, its channel also expands, so the edges of the holes must be strong and not subject to deformation. Therefore, for fastening plates from soft material, be it plastic or aluminum, steel inserts or washers should be used on both sides of the connecting parts. The same applies to connections that must be movable, hinged; they can also be used in combination with bushing washers, and their length must exceed the total thickness of the plates being fastened.
4
Unlike pull-out elements, conventional cast or stamped riveting elements must be installed using a certain amount of force applied to the closing end. This can be pressing or targeted blows to flatten the end of the rod coming out of the hole. The second option is most reminiscent of forging, especially since it is performed cold or hot. If the thickness of the riveting does not exceed 1 centimeter, you can use a cold forging of the closing head. If the diameter is more than 10 millimeters, then the fastening element must be heated to facilitate flattening of its end.
Rivet tool
As a rule, before hot riveting a rivet, it is heated in a forge, after which it is installed in the hole and a flat closing cap is made with several strong blows. In this case, there should be an anvil with a hole for the mounting head located below. For the cold method, a special tool is used - a striker with a semicircular hole, with the help of which an even hemisphere is formed by deforming the end coming out of the hole within the recess. Forging with a regular hammer gives the same result if you hit it on the end, directing the blows slightly sideways, from the center to the edges, but such a head will be less accurate.
5
As we have already said, the type of connection under consideration is one-piece, however, if you still need to disassemble the structure, the parts of which are riveted together, you can use several different methods. The most common one, which is usually applied to pull-out, explosive and split types of fasteners, as well as where countersunk heads are used, is drilling. To do this, a drill corresponding to the estimated or precisely known diameter of the hole is installed exactly in the center of the embedded or closing head, after which a hole is made to the required depth or a through channel. After this, with a few precise blows you can easily knock out the rivet.
Rivet Removal Tool
The second method is somewhat labor-intensive, however, it is quite effective for heads that are clearly visible above the surface, that is, for semicircular and conical ones. You will need a special chisel, shaped like a chisel, with which you need to cut off the cap, delivering sharp and strong blows to the back end of the handle. A sharpened chisel may also work, but this tool is recommended only for small-diameter rivets. Fasteners with a rod of about 1 centimeter or more are very difficult to cut in this way.
The easiest method for removing rivets with protruding heads is to use an angle grinder, commonly referred to as an angle grinder. It is best to install a cutting disc on it for this purpose, and, moving it from the side to the head, carefully cut it off. If there is a possibility of damaging the surface of the part from which the connection is being removed, it is recommended to use a coarse grinding disc, with which the head is simply carefully ground down to the base. Next, by installing any sufficiently sharp tool, for example, a punch, you can easily knock the rivet rod out of the hole with a strong blow of a hammer.
