Curved surfaces and centerlines
Download
1 / 9

Curved Surfaces and Centerlines - PowerPoint PPT Presentation


  • 142 Views
  • Uploaded on

Curved Surfaces and Centerlines . Sections 11.02 and 10.07 of Text . Objectives . Understand how curved surfaces will appear in each viewing plane. Create orthographic projections of objects with curved surfaces. Correctly use center marks and center lines to add clarity to drawings. .

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Curved Surfaces and Centerlines ' - aldis


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Curved surfaces and centerlines

Curved Surfaces and Centerlines

Sections 11.02 and 10.07 of Text


Objectives
Objectives

  • Understand how curved surfaces will appear in each viewing plane.

  • Create orthographic projections of objects with curved surfaces.

  • Correctly use center marks and center lines to add clarity to drawings.


Curved surfaces in orthographic
Curved Surfaces in orthographic

  • Similarly to the way inclined surfaces appear as an inclined edge in one view, curved surfaces will appear as a curved edge in one view and as a plane in the two remaining views.


Orthographic projection of a cylinder
Orthographic Projection of a Cylinder

  • The figure below shows an orthographic projection of a cylinder

    • Centerlines and centermarks are used to denote the center of a circular or cylindrical feature.

Centerlines

Visible extents of cylinder

Centermark

Circular end of Cylinder

CLICK


Centerlines
Centerlines

  • In order to help others understand your drawings, it is necessary to include centerlines and centermarks.

  • A centerline alerts readers that the edges next to the centerline may be optical limits of a curved surface and not true sharp edges.

  • This case occurs every time a curved surface is shown as a plane.

  • The most common occurrence of a curved surface in engineering drawings is a hole with hidden and center lines.


Centerlines1
Centerlines

  • Centerlines are drawn by alternating long and short dashes along the length of the center of the cylinder or a circular hole.


Centermarks
Centermarks

Hidden

lines

  • Centermarks show the center of a circular feature.

This arc is 180°

  • Centerline and centermarks are used where the arc of a surface is 180° or greater.

  • Note that both centerlines and centermarks extend past the extents of the circle or circular feature.

Center line

Centermark

This arc is 90°

Centermark, note the extension lines

Visible limit of arc

Hidden lines

Center line

Hidden

lines

Center lines


Line precedence
Line Precedence

  • Visible lines takes precedence over all other lines

  • Hidden lines take precedence over center lines

  • Center lines have lowest precedence

  • In this drawing, a visible line overlies a centermark.

  • Notice that the extension lines from the centermark are still visible.


Curved surfaces and centerlines1
Curved Surfaces and Centerlines

  • Use this time to practice making orthographic projections from objects with curved surfaces.

  • Do not forget to include centerlines and centermarks as needed!

  • In class assignment


ad