During the repair and construction process, it is important that the elements being connected are firmly and reliably fastened together. You can’t do without various hardware. Metal screws deserve special attention. They have become a part of everyday life; various photos of them can be seen in any construction catalogue.
Simple installation, reliability, and fastening strength allow them to be used in various areas of everyday life.
Features of application
An important advantage of self-tapping screws for metal is that in most cases drilling a special hole is not necessary. The presence of a tip with a drill is typical for many types of hardware. It is enough to pick up a screwdriver, and the self-tapping screw will go into the right place.
Being an important fastening element, it has specific features:
- Resistant to negative environmental factors;
- Available on shelves for every budget size;
- High wear resistance;
- Duration of operation;
- Easy to install;
- It is a high quality hardware product made from carbon steel.
Factors influencing the quality of self-tapping screws
Among the variety of hardware, those needed for working with metal differ from other varieties in appearance and technical characteristics.
The quality of self-tapping screws is influenced by 2 factors:
- Material of manufacture;
- Technology, accuracy of its adherence.
It is best to purchase hardware from companies that have proven themselves and have been working on the market for many years. The risk of running into Chinese steel is quite high.
It’s better to pay attention to well-known brands and buy screws not second-hand at a flea market, but in specialized stores. Then you can be 100% sure of the quality of the purchased products. At the same time, they will advise you on which metal screws are best to purchase, which is not suitable for working with thick or thin sheets of metal.
Technical characteristics: dimensions, weight and more ↑
Mainly made of carbon steel and galvanized. Thanks to the anti-corrosion coating, they last quite a long time - approximately 50 years. In addition to them, stainless steel hardware is available on the market, although they are much more expensive. As a rule, they are used in particularly critical areas for which it is necessary to provide increased strength
These products are also distinguished by the shape of the cap. She may have:
- standard type, that is, equipped with a screwdriver, or;
- with edges, for working with which special bits for roofing screws are used.
See what they might look like in the photo.
Further, depending on the type of roofing material, the caps can “sink” into the coating or, as in the case of the option with a press washer, press it, which will completely protect the hole from water penetration. The hat of the latter has the shape of a hemisphere.
Hardware can be equipped with a metal, often aluminum, washer with a rubber gasket. A sealing gasket made of a special EPDM material that self-vulcanizes during fastening and has a thickness of 2.8 mm is considered more effective and durable.
Among the wide variety of market offers, you can always select fasteners that have a length that exactly matches the wavelength of the roofing sheet.
Self-tapping screw heads
It is easier to determine the quality of hardware by its appearance: head, thread, slot. The required self-tapping screw size can be selected from the table.
As for the head, they are:
- Hexagonal, with a molded or stacked press washer;
- Under the countertop (the head is recessed);
- Hemispherical.
When you need to fasten fragile materials (for example, duralumin, brass), the use of metal screws with a press washer is mandatory so as not to break the fasteners during the process of joining them.
Roofing screws
Self-tapping screws with a hexagonal head have a wide range of applications, but most of all they are used for fastening roofing coverings such as metal tiles and corrugated sheets, as well as components for them, for which they received the general name “roofing”.
- The length of self-tapping screws with a hexagonal head varies from 19 to 100 mm.
- Rod diameter 4.8 and 6.3 mm.
They are equipped with a washer with a rubber gasket, which is responsible for the tightness of the connection, which is important for installing a roof (to prevent leaks).
In terms of color diversity, caps can be of very different colors: red, brown, green, white and others. The color of the cap is matched to the color of the material being fixed and is marked according to the Ral and color standards.
There are also self-tapping screws without painting - just with a galvanized head and washer.
To fasten (tighten) these screws, bits with an internal hexagon are used.
Bit size:
- for self-tapping screws with a core diameter of 4.8 mm - 8 mm bit
- with a rod diameter of 6.3 mm - 10 mm bit
Confirmat - furniture screw
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Confirmats are used when assembling furniture.
The most used ones are 50 mm long with a hex head.
This type of fastener requires mandatory pre-drilling. There is a special confirmation drill for this.
To tighten the confirmations, use hexagons or bits for HEX 4 brand screwdrivers.
Splines
Self-tapping screws for metal are not driven in, but tightened. Their head has specific notches - slots.
It is much more convenient in some situations to use hardware with a hex head, in others - with slots. It is important to understand what kind of metal you will have to deal with - corrugated sheets, angles, channels or pipes of various profiles.
The most common slots that can be seen on self-tapping screw heads are as follows:
- Straight;
- Cross-shaped;
- Star;
- Square;
- Hexagon;
- With a secret.
You also need to understand: some screws (for example, with an asterisk slot) cannot be screwed in in large quantities, since you need to carefully connect the screwdriver bit to the head.
If you are in a hurry or tired, you can ruin the material and “lick the inner edges” of the screws without screwing in the required number.
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Self-tapping screws
One of the areas of our work is the supply of self-tapping screws and a wide range of screws made in China.
Self-tapping screws come in various names:
- plasterboard-wood (GD) black
- plasterboard-metal (GM) black
- for thin plates (MM sharp) galvanized
- for thin plates with drill (MM drill) galvanized
- roofing (KRS) galvanized
- roofing (KRS) painted according to RAL
- universal galvanized (Schutz
Self-tapping screws also differ in design and are divided into:
- Self-tapping screws with a countersunk or semi-countersunk head
- With a semicircular head (with or without a press washer)
- With cylindrical head
- Hex head
In terms of size, self-tapping screws differ in the diameter of the rod, which corresponds to a number of lengths. The standard diameters of screws for wood and metal are: 3.5 mm, 3.8 mm, 4.2 mm, 4.8 mm. Thus, the designation of a self-tapping screw consists of diameter and length, for example, like this:
3.5x76 or 4.8x152mm
You can buy self-tapping screws and self-tapping screws in our online store. To do this, information on weight, size of screws and other characteristics will help you. If you have any questions, please contact us by multi-channel phone and our managers will advise which screws are best to choose for your purposes.
Table for calculating the weight of self-tapping screws GD and GM per 1000 pieces
| Size, mm | Weight, kg | |
| 3.5x16 | 0,80 | |
| 3.5x19 | 0,91 | |
| 3.5x25 | 1,08 | |
| 3.5x32 | 1,25 | |
| 3.5x35 | 1,43 | |
| 3.5x41 | 1,69 | |
| 3.5x45 | 1,83 | |
| 3.5x51 | 2,00 | |
| 3.5x55 | 2,38 | |
| 3.8x64 | 2,64 | |
| 4.2x75 | 3,50 | |
| 4.2x89 | 4,04 | |
| 4.8x100 | 6,20 | |
| 4.8x110 | 6,70 | |
| 4.8x127 | 8,07 | |
| 4.8x152 | 9,20 |
Note: the actual weight of the screws may differ in one direction or another from the theoretical one.
Table for calculating the weight of MM screws per 1000 pieces
| Size MM, mm | Weight, kg | |
| 4.2x13 | 1,15 | |
| 4.2x16 | 1,33 | |
| 4.2x19 | 1,44 | |
| 4.2x25 | 1,80 | |
| 4.2x32 | 2,19 | |
| 4.2x38 | 2,49 | |
| 4.2x41 | 2,64 | |
| 4.2x51 | 3,23 |
Note: the actual weight of the screws may differ in one direction or another from the theoretical one.
Table for calculating the weight of roofing screws per 1000 pieces
| Size, mm | Weight, kg | |
| 4.8x29 | 5,16 | |
| 4.8x35 | 5,67 | |
| 4.8x51 | 5,92 | |
| 4.8x60 | 7,58 | |
| 4.8x65 | 8,15 | |
| 4.8x70 | 8,42 | |
| 4.8x80 | 9,46 | |
| 5.5x19 | 5,14 | |
| 5.5x25 | 5,70 | |
| 5.5x32 | 6,45 | |
| 5.5x38 | 7,10 | |
| 5.5x51 | 8,85 | |
| 6.3x19 | 7,94 | |
| 6.3x25 | 8,78 | |
| 6.3x32 | 10,60 | |
| 6.3x38 | 11,80 | |
| 6.3x51 | 12,88 | |
| 6.3x80 | 17,84 | |
| 6.3x152 | 29,30 |
Note: the actual weight of the screws may differ in one direction or another from the theoretical one.
Table for calculating the weight of universal self-tapping screws per 1000 pieces
| Size, mm | Weight, kg | Size, mm | Weight, kg | |
| 2.5x12 | 0,33 | 4.5x25 | 1,82 | |
| 2.5x16 | 0,39 | 4.5x30 | 2,20 | |
| 2.5x25 | 0,58 | 4.5x35 | 2,52 | |
| 3.0x10 | 0,39 | 4.5x40 | 2,75 | |
| 3.0x12 | 0,43 | 4.5x45 | 3,12 | |
| 3.0x16 | 0,56 | 4.5x50 | 3,30 | |
| 3.0x20 | 0,62 | 4.5x60 | 3,95 | |
| 3.0x25 | 0,78 | 4.5x70 | 4,60 | |
| 3.0x30 | 0,92 | 4.5x80 | 5,24 | |
| 3.0x35 | 1,06 | 5.0x20 | 1,92 | |
| 3.0x40 | 1,21 | 5.0x25 | 2,32 | |
| 3.5x16 | 0,72 | 5.0x30 | 2,73 | |
| 3.5x20 | 0,87 | 5.0x35 | 3,12 | |
| 3.5x25 | 1,02 | 5.0x40 | 3,38 | |
| 3.5x30 | 1,21 | 5.0x45 | 3,70 | |
| 3.5x35 | 1,38 | 5.0x50 | 4,16 | |
| 3.5x40 | 1,58 | 5.0x60 | 4,80 | |
| 3.5x45 | 1,82 | 5.0x70 | 5,52 | |
| 3.5x50 | 2,02 | 5.0x80 | 6,32 | |
| 4.0x12 | 0,85 | 5.0x90 | 7,00 | |
| 4.0x16 | 0,98 | 5.0x100 | 7,70 | |
| 4.0x20 | 1,17 | 5.0x120 | 9,13 | |
| 4.0x25 | 1,40 | 6.0x30 | 3,85 | |
| 4.0x30 | 1,62 | 6.0x40 | 5,02 | |
| 4.0x35 | 1,87 | 6.0x45 | 5,52 | |
| 4.0x40 | 2,08 | 6.0x50 | 6,03 | |
| 4.0x45 | 2,33 | 6.0x60 | 7,22 | |
| 4.0x50 | 2,60 | 6.0x70 | 8,26 | |
| 4.0x60 | 3,12 | 6.0x80 | 9,30 | |
| 4.0x70 | 3,44 | 6.0x90 | 10,40 | |
| 4.0x80 | 3,95 | 6.0x100 | 11,45 | |
| 4.5x16 | 1,20 | 6.0x120 | 12,53 | |
| 4.5x20 | 1,50 | 6.0x140 | 16,00 |
Note: the actual weight of the screws may differ in one direction or another from the theoretical one. PRICE LIST
Thread
The next point that you need to pay attention to when choosing high-quality screws for metal is the thread. Depending on the type of material that needs to be fastened, it can be:
- Large, with a rare step. Designed to work with non-metallic soft materials: plaster, plastic, wood;
- Average. Available with universal self-tapping screws that can be used to fasten anything;
- With a herringbone profile, for a driven dowel;
- Double-threaded, for working with metal sheets. Such hardware may have a drill at the tip for easy screwing;
- Asymmetrical. Used exclusively in the production and assembly of furniture;
- Variable, with notch. When you need to fasten it to a brick or concrete wall without driving in a dowel, you use a self-tapping screw with this type of thread.
Types of self-tapping screws
The variety of building materials can confuse an inexperienced beginner. Nevertheless, you need to navigate the entire heap of the offered assortment, at least in order to buy everything you need at a reasonable price.
All self-tapping screws existing on the market can be divided into 3 large classes:
- On wood (with a sharp end). They are usually black in color;
- For metal (with a drill at the end, painted or galvanized);
- Universal. They can be either black, gray or golden.
The press washer is often an integral part of the hardware. It can be either collapsible or cast. This design of the self-tapping screw allows you to compress the parts being connected much more strongly without damaging them. The presence of a drill allows you to eliminate the use of a drill and significantly save time in the process of roofing work.
Self-tapping screws with a pointed end make it easy to connect materials made of wood, fiberboard, chipboard, or hang a shelf or cabinet on the walls.
Photo of self-tapping screws for metal
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