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In lamiera processing, there are many types of common tools for sheet metal. According to their different uses, commonly used sheet metal tools and fixtures can be divided into scribing tools, manual forming tools, and mechanical forming tools (usually called stamping tools). ) And several categories such as component marking and assembly fixtures (tire molds). In addition, in order to bundle and carry, various spreaders are also used in lamiera assembly.

 Scribe Tool

Scribing is the most basic operation in sheet metal processing. It is a prerequisite for the unfolding and blanking of sheets and profiles, and it is also an important part of subsequent parts processing and assembly. Scribing needs to be done with a scribing tool.

The Name and Purpose of Commonly Used Marking Tools

Tool Name	Foto	Purpose
Flat Plate		It is generally made of cast iron, and the surface is finely planed or scraped. The working surface is the benchmark for marking and testing. The accuracy of the working surface is divided into six grades, including 000, 00, 0, 1, 2, and 3. Generally, the plate used for marking is level 3, and the rest are used for quality inspection
Scribing needle		Generally, it is made of spring steel wire with a diameter of Φ3-6mm or carbon tool steel after sharpening and quenching. It can also be made by welding the end of carbon steel wire with cemented carbide. The scribing needle is 200-300mm long, and the tip is ground to 15°-20°, used for scribing on steel
Scribing plate		The scribing plate is easy to adjust and use. One end of the scribing needle is welded with a high-speed steel tip, which can be used for scribing on steel, and one end is bent into a hook shape for easy alignment and use.
Scribing gauge		It is made of tool steel or stainless steel, and the tips of the feet are hardened or welded with a section of cemented carbide. Used to draw circles, arcs, equal angles, and equal line segments, etc.
Vernier scribing gauge		The vernier marking rule has a vernier scale, the vernier marking needle can adjust the distance, and the other marking needle can adjust the height, suitable for large-size marking and marking on the stepped surface
Large size scribing gauge		This kind of ruler is similar to the vernier ruler, but there is a no vernier scale and height adjustment device, suitable for large-size marking
Special scribing gauge		Similar to the vernier ruler, the hole on the part can be used to draw concentric circles or arcs, or you can draw lines on the stepped surface
Vernier height gage		This is a precision scoring and measuring tool. When using it, pay attention to protecting the scoring blade.
One-leg compass		The one-leg compass is generally forged from tool steel, and the toes are hardened by quenching. Used to find the center of a round workpiece, draw parallel lines with the machined straight surface
Sample punch		Made of tool steel or spring steel, the tip is ground to about 60°, after quenching and hardening, it is mainly used to punch out uniform punches on the line drawn on the surface of the workpiece to prevent the drawn lines from being wiped off
Center frame		Used for centering hollow round workpieces
Square box		A hollow cube made of cast iron, each surface is scraped, adjacent planes are at right angles to each other, and the opposite planes are parallel to each other. Use the clamping device to fix the small workpiece on the square box. When marking the square box by 90°, the mutually perpendicular lines on the workpiece can be drawn in one installation. The V-shaped groove on the square box is parallel to the corresponding The plane is used for placing cylindrical workpieces
90°Square ruler		It is used to align the vertical position of the workpiece on the platform when scribing. It can also be used as a guide tool for scribing vertical or parallel lines.
V-shaped iron		It is made of cast iron or carbon steel, and the adjacent surfaces are perpendicular to each other. Used to support shaft parts when marking
Jack		Used to support roughcasts or irregularly shaped workpieces for alignment and scribing

The Main Points of Scribing in Common Tools for Sheet Metal

• Scribing plate: The scribing plate is the reference surface of the scribing work. Its flatness directly affects the accuracy of the scribing. Therefore, you should always pay attention to the maintenance of the plate. Main content: Try to use the scribing plate evenly throughout to avoid local abrasion; keep the plate clean to prevent iron filings, sand, and other impurities from damaging the plate; when using the plate, the tools used on it should be handled gently. Avoid hitting the surface, let alone hit the surface with a hammer; after use, wipe it clean and apply anti-rust oil.

• Jacks: Jacks are usually used to support and adjust large blanks or irregularly shaped workpieces for alignment and scribing. When using, pay attention to the following items: the bottom of the jack should be cleaned, and the supporting point should not be tilted on the workpiece. Or the parts that are easy to slip should be placed smoothly. If the jack needs to be pushed on the arc surface, a larger punching hole should be punched at the jacked position, so that the jack top is in the punching hole to prevent sliding; Generally, three jacks are shared at the same time. At this time, the support points of the three jacks should be as far as possible from the center of gravity of the workpiece, and the triangle area formed by the three support points should be as large as possible. Generally, two jacks are placed on the heavier end of the workpiece, and one on the lighter end; when the workpiece needs to be erected and scribed, and the three jacks are on a narrow and long plane, the workpiece should be lifted with the help of a crane and a safety rope. Play an insurance role. Generally, the rope is not tensioned, and the jack has room to adjust the height of the workpiece. In case the workpiece falls, the rope will use force; when the workpiece is heavy or the area supported by the three jacks is small, a few hard pieces can be placed under the workpiece block. In order not to change the supporting planes of the three supporting jacks, there is a small distance between these wooden blocks and the workpiece, which is mainly used to bear the weight in the event of an accident.

• Scribing needle: The scribing needle is the basic tool for marking the workpiece. The most commonly used scribing needle is straight. For places where the straight scribing needle cannot be drawn, an elbow scribing needle is used. When scribing with ascribing needle, the needle tip should be steadily dragged against the steel ruler and slant the steel ruler 20°~25°, do not sway the needle left and right when scribing, try to make single scribing (see picture 1). If the same line is drawn repeatedly, the line becomes thicker or does not overlap and is blurred, which will affect the quality of the line.

• Scribing block: The scribing block is a tool used for three-dimensional scribing and aligning the position of the workpiece. When using the scribing block, the straight end of the scribing needle is used for scribing, and the elbow end is used for aligning the workpiece. The marking position. The protruding part of the scribing needle should be as short as possible; when dragging the base for scribing, make it close to the flat surface. When scribing, the scribing dial is inclined 30°~60° in the direction of the scribing movement (see picture 2).

• One-leg ruler: Single-leg ruler is used to determining the center position of the shaft and hole. The following shows how to use the one-legged ruler. (see picture 3)

• Sample punch: When punching the eye with the sample punch, open the body and tilt the punch outward so that the punch tip is aligned with the center of the line or the center of the drawn hole. (see picture 4)

Hand Forming Tools

Manual forming is one of the most basic operating skills for sheet metal processing. In the case of small production batches or limited by production and processing equipment, manual forming is often used. Commonly used manual forming tools and the main points of use are as follows.

Hammer

Hammers are used for sheet metal cutting, correction, and section steel correction during manual forming. There are sheet metal hammers, fitter’s hammers, and sledgehammers. The following table is about specifications and uses.

Nome	Foto	Specifications/kg	Purpose
Ball hammer		0.25、0.5、0.75、1、1.1、1.25、1.5	For general hammerings, such as cutting, straightening, riveting, etc.
Beveling Hammer		0.125、0.25、0.5	Used for flattening and flanging of thin metal plates, etc.
Sledge hammer		0.9-10.9	Used for manual free forging and hammering of workpieces, such as raw material correction, bending, etc.
Sheet metal hammer		0.25-0.75	Used for edge laying and closing processing of sheet metal
Dedicated hand hammer		0.25-0.75	Used for bending of thin plates, edge laying, edge closing, pulling edge, and arching processing
Copper hammer		0.25、0.5、0.75、1.0、1.25	Used for component assembly and mold assembly, etc.
Wooden hammer		0.25-1.5	Used to hammer thin steel plates, non-ferrous metal plates, and metal surfaces with high surface roughness requirements to prevent hammer marks
Stick		45mm*400mm	Used for crimping and seam connection of thin metal plates

Forming Aids

Forming aids are used to complete various types of manual forming processing auxiliary forming and orthopedic purposes, mainly square bars, round bars, tires, platforms, etc. Ftable.

Nome	Foto	Purpose
Square bar		Used for thin plate bending and forming, seam, etc., and its end is used for thin plate edge setting, pulling edge, etc.
Round bar		Used for thin plate bending forming, etc., and its end is used for arching, etc.
Type tire		Used for thin plate arching, etc.
Platform		Used for orthopedics or assembly of workpieces
Platform with holes		Insert a clamp into the hole to fix the workpiece, used for the correction or forming of the profile or tube
Platform with T-slot		In the T-shaped groove, insert bolts to fix the workpiece, which is used for workpiece correction or forming, assembling and welding, etc.
Lever		Mainly used for the correction and turning of profiles, and can also use the principle of the lever to clamp the workpiece

Stamping Tools

Stamping is in sheet metal processing through the use of mechanical equipment on the sheet metal, pipe material, or steel processing, stamping commonly used tools are mainly charging tools and feeding tools, die fastening tools.

Material Charging and Feeding Tools

When stamping medium and small workpieces, the single blank is put on the mold, or the stamping parts and waste materials are taken out after stamping. It is necessary to use the material taking and discharging tools. It is strictly prohibited to reach directly between the upper and lower dies by hand, so as to avoid the occurrence of hand breaking accident. There are several kinds of material taking and discharging tools.

• Elastic clamps and hooks are mainly used for taking and placing small billets or workpieces. They are the most simple hand tools. Their shape and structure are shown in the picture.

• Pneumatic clamps use compressed air as the power to clamp the hand tools of medium size workpiece, its shape structure is shown in the picture.

• Vacuum chuck：It is a manual tool that uses vacuum suction to take and send the workpiece, to take and send the plate-shaped workpiece. Its external structure is shown in the picture.

• Electromagnetic chuck: An electromagnetic chuck is a hand tool that uses a direct current electromagnet to adsorb the workpiece. Its shape and structure are shown in the following picture. When the switch is pressed, the power supply is connected, the magnetic cover and magnetic core generate a magnetic field under the action of the current coil, the billet is absorbed, the switch is closed, the power supply is cut off, the magnetic force is eliminated, the billet falls in the specified position of the punching die, the magnetic suction cup can be removed for stamping. The whole operation is convenient, safe, and fast.

Mold Fastening Tools

Commonly used die fastening tools include pressing plate, T-bolt, hexagonal bolt, pad and other fasteners.

In the small punch and part of the medium punch, the upper die commonly used to insert the punch slider hole in the method of fixing, in the large punch and some medium punch, pressed plate, bolt, and nuts are used to fasten the upper die. For the large die used on the large punch press, multiple bolts or T-bolts and nuts are used to fasten the template directly, instead of pressing the plate.

When tightening screws of the upper and lower die, it is not appropriate to tighten screws or nuts on one side completely before starting to tighten the other side. Instead, screws or nuts on each side of the die should be tightened alternatively and gradually to avoid deviation or tilting of the upper and lower die in the tightening process, thus destroying the assembly accuracy and fit clearance of the original die.

The following picture shows several correct and incorrect ways of fastening the lower die to the workbench with pressing plates, bolts, and cushions. Picture (a)~(d) of the picture is the schematic diagram of the correct installation, and the rest is the incorrect installation. Picture (e) the main mistake is insufficient stiffness of the press plate; Picture (f) the main error is that the height of the support is not equal to the height at which the lower die seat is pressed; Picture (g) the main mistake is that there is no special use for the cushion iron and gasket. The cushion iron and gasket for fastening the mold should be of special use. The main mistake in the picture (h) is that the relative position of the press plate, the screw, and the die is not appropriate. The proper position should be arranged according to the size shown in the picture(d).

In the process of punching, the vibration of the press may cause the loosening of the fastening parts of the fixed punching die, so the operator must pay attention to and check the working condition of the fastening parts at any time. The following picture shows several methods to prevent the loosening of the fastening nut.

Clamp

Clamps are mainly used for the positioning and clamping of the workpiece in the marking, assembly, and welding work. According to the clamp movement, it can be divided into the manual, pneumatic, hydraulic, and magnetic clamp and other categories. Its types and uses are shown in Table.

Nome	Foto	Purpose
Wedge clamp		Use an open or perforated splint and wedge to cooperate to clamp the work. When the wedge is driven in, the inclined surface of the wedge can generate clamping force, so as to achieve the purpose of clamping
Screw clamp		The function of the screw is used to clamp, pull, top, support, and other functions. The arcuate spiral clamp is a commonly used clamp in the clamp
		With the help of l-shaped iron and screw to squeeze the role
		When the bolt is rotated, the distance between the two elbows can be changed by using the opposite threads at both ends of the bolt
		The screw of the pusher has positive and negative threads. When the screw is rotated, it plays the role of tightening or spreading.
Toggle clamp		Used for the splicing of medium and thin plates, it is characterized by fast clamping and a wide adjustment range of clamping thickness
Eccentric clamp		Rotate the eccentric wheel with the handle to change the eccentricity e to achieve the purpose of clamping. The advantage of the eccentric clamp is that the action is fast, but the disadvantage is that the clamping force is small
Pneumatic clamp		The pressure of compressed air is used to push the piston rod to move back and forth to achieve the purpose of clamping. Suitable for clamping of medium and thin plate components
Hydraulic clamp		It is mainly composed of a hydraulic cylinder, piston, and piston rod. The hydraulic cylinder causes the piston rod to move linearly and pushes the lever device to clamp the work. The advantage of hydraulic clamps is that the clamping force is large and the work is reliable; the disadvantage is that the liquid is easy to leak and the maintenance is inconvenient.
Magnetic clamp		There are two types: permanent magnet and electromagnetic. This kind of fixture uses a magnet to hold the steel plate and relies on a screw or lever to clamp the work by magnetic force or electromagnetic pressure.