PartDesign Revolution

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Revision as of 19:53, 13 February 2016 by R-Frank (talk | contribs)

PartDesign Revolution

Menu location
PartDesign → Revolution
Workbenches
PartDesign, Complete
Default shortcut
None
Introduced in version
-
See also
None

Introduction

This tool revolves a selected sketch or 2D object about a given axis. For all the following explanations of this command the example sketch below will be used:

Example sketch: A complex sketch with many constraints. Sketch is oriented in the x-y plane, with x being the horizontal axis, and y being the vertical axis (shown in image as the two blue lines). Other important things to note about this sketch is that it are mirrored about the y axis and that the base of it is coincident with the x axis.

Options

When creating a revolution, the 'revolution parameters' dialogue offers several parameters specifying how the sketch should be revolved.

Axis

This option specifies the axis about which the sketch is to be revolved. Currently, by default only the horizontal or vertical sketch axis can be selected here. However if the sketch which defines the feature to be Revolved also contains a construction line (or lines), then the drop down list will contain one custom sketch axis for each construction line. The first construction line will be labelled 'Sketch axis 0'. After creation an arbitrary axis can be defined in the Properties table. Base is a point through which the axis goes. The axis option itself takes three arguments, which are passed as numbers to either the x, y, or z boxes in the tool. Adding a value of 1.0 to only one of the boxes will cause the tool to make the revolution about that axis. Example revolutions 1, 2 and 3 in the examples section demonstrate scenarios where the example sketch is revolved about either the x or the y axis. Adding a non-zero value to more than one of the axes will cause the part to be revolved by a weighted amount in each axis. e.g. an x value of 1 and a y value of 2 will mean that the revolution about the y-axis is twice as strong as that about the x. This is fairly difficult to comprehend, Example Revolution 4 shows an example where more than one of the boxes has a non-zero value.

Angle

This controls the angle through which the revolution is to be formed, e.g. 360° would be a full, contiguous revolution. The images in the examples section demonstrate some of the possibilities with specifying different angles. It is not possible to specify negative angles (use the Reversed option instead) or angles greater than 360°.

Symmetric to plane

The revolution will extend half of the specified angle in both directions from the sketch plane.

Reversed

The direction of revolution will be reversed.


Examples

Example revolution using a construction line as the Revolution axis: In this image the angle is 75°, revolution is about the construction line (Sketch axis 0)

Note: Unlike the above, all these examples below refer to Base, Axis and Placement being edited directly through the feature properties table.

Example revolution 1: In this image the angle has been set to 70°, revolution is about the x-axis and there is a y-offset of 100mm. The sketch is the face not shown in the image (i.e. the 'back' face).
Example revolution 2: In this image the angle is 70°, revolution is about the y-axis and there is a y-offset of 100mm.
Example revolution 3: In this image the angle is 270°, revolution is about the x-axis and there are 0 offsets
Example revolution 4: In this image the angle is 270°, revolution is about the x-axis (value 1.00) and the y-axis (value 2.00) and there is a y-offset of 100mm

Useful links

An example with the practice on the forum.