Sectioning or crosshatching lines

When you go to a museum, you often see artefacts that have been cut up. For example, to illustrate how a petrol engine works, the cylinder block can be cut in half and the cut faces are invariably painted red. In engineering drawing, cross-hatching is the equivalent of painting something red. It is used to show the internal details of parts which otherwise would become too complex to show or dimension.

The cross-hatch lines are usually equi-spaced and, for small parts, cover the whole of the 'red' cut area. They are normally positioned at 45° but if this is awkward because the part itself or a surface of it is at 45°, the hatching lines can be at another angle. Logical angles like 0°, 30°, 60° or 90° are to be preferred to peculiar ones like 18° (say). If sectioned parts are adjacent to each other, it is normal to cross hatch in different orientations (+ and -45°) or if the same orientation is used, to use double lines or to stagger the lines. Examples of single and double + and -45° cross-hatching lines are shown in the vice assembly drawing in Figure 3.1. An example of staggered cross-hatching is shown in the inverted plan drawing of the movable jaw in Figure 3.2.

If large areas are to be sectioned, there is no particular need to have the cross-hatching lines covering the whole of the component but rather the outside regions and those regions which contain details.

When sections are taken of long parts such as ribs, webs, spokes of wheels and the like, it is normally the convention to leave them unsectioned and therefore no cross-hatch lines are used. The reason for this is that the section is usually of a long form such that if it were hatched it would give a false impression of rigidity and strength. In the same way it is not normal to cross hatch parts like nuts and bolts and washers when they are sectioned. These are normally shown in their full view form unless, for example, a bolt has some specially machined internal features such that it is not an off-the-shelf item. Example of threads that are not cross-hatched can be seen in the vice assembly drawing in Figure 3.1.

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Responses

  • Elise Young
    What is sectioning in drawing engineering?
    8 years ago
  • ZACH
    What is hatching used for in engineering drwaing?
    8 years ago
  • Simona De Luca
    What is a staggered hatching drawing?
    8 years ago
  • elia
    When should hatching be used in engineering drawing?
    8 years ago
  • heike
    Do you cross hatch bolts in section?
    7 years ago
  • Madihah
    Does a bush get sectioned in mechanical drawing?
    7 years ago
  • Simona Sagese
    HOW TO DRAW ENGINEERING HATCHED LINE?
    7 years ago
  • sophia
    Do you cross hatch an external thread ON A DRAWING?
    6 years ago
  • robert
    What should be not hatched when sectioning?
    6 years ago
  • claudia
    What is cross hatching on an engineering drawing?
    6 years ago
  • segan medhanie
    How to show bolts in hatched section view?
    6 years ago
  • Elias Filmon
    Are bolt sectioned in sectional drawings?
    3 years ago
  • lisa murphy
    Do you section a Bush in technical drawing?
    3 years ago
  • tove
    Do we hatch nuts and bolts in engineering drawing?
    2 years ago
  • Lennox
    How does hatching line is drawn in an orthographic projection?
    2 years ago
  • dominik
    Do you cross hatch sectioned webs in technical drawings?
    2 years ago
  • Judy
    Why cross hatching is used in assemble drawing?
    2 years ago
  • katja
    Why hatching lines is used in assembly drawing?
    2 years ago
  • SEGAN
    What do you mean bh hatching lines in engineering drawing?
    2 years ago
  • Dean
    Do they section bushes in engine drawing?
    2 years ago
  • ALEM
    Which pencil is used for sectioning?
    2 years ago
  • YVONNE
    Which part not section druning sectioning?
    2 years ago
  • DUILIO
    How to draw hatch line in sectioning?
    2 years ago
  • Guido Brownlock
    Where to hatching and not to hatch in egd?
    2 years ago
  • arsenio
    Do we done hatching on washer in assembly drawing?
    2 years ago
  • Jackie
    How to cross hatch parts?
    2 years ago
  • darragh wood
    How to hatch lines in technical drawing?
    1 year ago
  • pia
    How to hatch a bracket and shaft EGD Sectioning?
    1 year ago
  • robinia
    What is the purpose of "Hatching" in EGD?
    1 year ago
  • almaz
    Do you hatch a bolt in machinal assembly?
    1 year ago
  • frank loewe
    Do you hatch a washer sectional orthographic?
    12 months ago
  • margaret kelley
    What not to hatch when sectioning in drawings?
    11 months ago
  • SANDRA
    What does hatched lines mean on an engineering drawing?
    10 months ago
  • mohammed
    What are the components not hatched when sectioning in engineering drawing 2?
    10 months ago
  • CARA
    What is hatch lines in engineering drawing?
    9 months ago
  • Negassi Girma
    What is a cross section hatching?
    9 months ago
  • beulah madrigal
    What does cross hatching indicate in engineering drawings?
    9 months ago
  • noora
    What slanted cross hatch lines represent in section drawings?
    9 months ago
  • Janina
    Why do you apply cross hatching to a sectional construction drawing?
    8 months ago
  • Sylvie
    How to read complex engineering drawings?
    8 months ago
  • azzeza
    How to draw hatch lines in engineering drawings?
    8 months ago
  • chantelle
    How do you cross hatch in orthogonal drawing?
    6 months ago
  • GIOACCHINA MANFRIN
    Can you make hatched lines on drawings?
    6 months ago
  • mandy engel
    How do you annote a cross hatch finsh ona drawing?
    6 months ago
  • robert
    What do hatched lines show o an orthographic drawing?
    6 months ago
  • joann
    What are cutting planes and hatching in engineering drawings?
    6 months ago
  • delinda
    What coponents do you not cross hatch?
    6 months ago
  • Wolfgang Hofmann
    Can nuts be sectioned IN MECHANICAL DRAWING?
    5 months ago
  • ted
    What not to cross hatch in sections?
    5 months ago
  • PRIMULA
    How to show sectioned materials?
    5 months ago
  • LIDYA
    What do crosses represent in engineering drawings?
    5 months ago
  • jessica
    What shouldn't you cross hatch in a section view?
    3 months ago
  • anna-liisa
    Does a wheel sectioned in engineering?
    3 months ago
  • reuben
    How to show a cross sectioned thread?
    3 months ago
  • Malva Brandybuck
    What are supposed to be hached marked on an engineering drawing?
    2 months ago
  • Peter
    When is cross hatching used technical engineering?
    2 months ago
  • Jens
    Do you cross hatch a thin surface?
    2 months ago
  • seppo
    Which parts not be cutting in drawings?
    2 months ago
  • publio
    How to cross hatch multiple areas on a section view?
    1 month ago
  • Aarne
    How to draw section line in engineering drawing?
    5 days ago

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