Marking out

Marking as the attachment is referred to by the dimension lines on a workpiece surface by scribing.

Principle

Mass for drilling, cutting, etc., are applied in the form of engravings, or the lines drawn on the workpiece made ​​of wood, metal or stone. It also serves as the "mediation" of shape outlines with heavier castings and forgings and manual arc cutting. The marking is carried out with a pencil, chalk or a scriber or a drawing compass.

Pencils and chalk will inter alia be used when a scratching of the surface must be avoided (damage to the surface or cracking notch effect ). Sensitive surfaces, or those that are to suffer no damage can be covered with easily detachable paper on which the pencil plan takes place.

Sometimes the attached rice lines are complemented by grains points to it still being able to safely identify them by various machining processes, in which the lines are increasingly blurred. Large workpiece contours are marked with a double grains (two closely spaced peaks ) along the scribe line.

To make the crack on metallic surfaces more visible, using special dark, copper- sulfate-containing coatings, which are applied to the workpiece before scribing and so emphasize the bare metal cracks. In practice, a waterproof pencil is used instead of a marking color often. Also applied wet chalk is possible when coarse parts are used with greater inaccuracy.

The marking in tightening launched a contour (template) to the working work carried out as previously described. An already high manufacturing condition can be projected through a mask onto the workpiece.

The marking shall be made taking into account the subsequent manufacturing processes. Thus, to determine whether more needs to be present, for example, when cutting the scribe mark on the finished part or not.

Tools

All WHEELER are part of the metal art. They are found mainly in workshops with small batch and individual production, but also in tool of large companies. A meaningful life (metal technology: service life ) and to achieve a recognizable Ritz effect on the workpiece, these tools are hardened or wear a lace made ​​of hard metal.

Also in woodworking scribers are sometimes used. The Japanese wood artisans, however, preferred a special knife ( Shirabiki ) to attach to wood surfaces particularly precise lines for the processing of meaning.

Tack

It is made of steel, steel with carbide tip or brass. Typical scribers are about 20 to 30 cm long and have a diameter of about 3-4 mm. They are usually pointed at both ends very long, one end is angled approximately 3 cm by 90 degrees. The apex angle is approximately 15 degrees. Typical models have in the middle as a handle, a sheath of about 10 cm long, knurled piece of pipe. Other variants are designed as ball pen with carbide tip or as a simple, elongated needle.

Vernier height gauges

Vernier height gauge or surface gauge serve the scribing guide lines that are parallel to the bearing surface of the marking gauge. Marking gauge made ​​from a heavy base on which a vertical stand is fitted with a scale. The stator surrounds a vernier or digital working, vertically movable unit whose tack continue to be adjusted horizontally by means of two screws.

• Vernier height gauges

Analog vernier

With electronic digital display

Anreißtisch or marking plate

Thus the scribe line runs absolutely straight, marking gauge are guided on a marking plate or a Anreißtisch that consist of cast iron or granite. You assign the event of damage to any bulges, and thus they continue a high level of flatness. These tables are sometimes on three legs, so as not to wobble on uneven ground.

To facilitate guiding of the parallel eradicators, graphite is spread in the form of flakes on the Anreißtisch. Either secure clamping devices for marking the position of the prepared pieces and allow a repetition effect, or it is located on the plate a heavy, solid cast-iron mooring angle to it eg Creating a small sheet metal parts and to be able to press down to fix with the second hand.

It may only be placed on the marking plate no other tools or workpieces, as these could damage the marking plate otherwise.

Many Anreißtische are equipped with a so-called Anreißmaschine. Marking machines are 3-axis movable stand. The three axes are nowadays equipped with a wheel alignment system. The display of the axis positions is via a measurement counter. The movement of the axes is performed either manually via handwheels or motorized. The marking of work pieces takes place through replaceable marking tools such as scribers or circle.

Application: marking of castings for machining, scribing of prototype parts, marking of welded structures

Geometric determination and testing with the Anreißverfahren

• Geometric methods of solution

Determining a right angle to / from a line.

Several scribe lines also serve regularly in the work of preparation for it, before or between operations, such as to determine on different machines, measurement points and levels of workpieces and then to identify it. In this case (eg provision of a solder or an exact right angle between two lines without tearing Anreißtisch ) more complex classical methods of geometry for the application come

Attaching a height level of an upright workpiece and the additional attachment of a side dimension than height dimension, after assignment of the workpiece on the side, results in an exact intersection of the two dimensions, for example, for a dimensioned in two planes center of a yet to be fitted hole. Similarly, with the aid of a prism for rotating parts by the application of three lines at the same level, on the rotation of the rotary member in the prism checked by approximately 120 degrees, the height dimension used, and the axis of rotation and then in detail.

Critical considerations

Scribers and Anreißmesser can put on top of material a notch that can trigger a notch effect / notch effects with the possibility of structural damage, despite their small size. This is particularly true for aluminum and its alloys. In aircraft scribers are regularly banned and replaced by special pens that do not scratch the surface of the material.

Other meanings

When marking is also referred to

• The superficial response to a problem ( " touch on a topic " )
• To start a fuel-powered engine with a proper motion of the machine ( eg the engine of an aircraft by händisches turning the propeller on the leaf ).
• For the teaser in journalism, pointing to a contribution, provides guidance on the content and enticed to click, see teaser.

• Engineering Design
• Machining