Lesson 3-2 Isometric Drawing

Isometric commands is one of the easiest ways to give a drawing in 2-D a 3-D look. Isometric drawing was the standard way of drawing 3-D before we were able to do true 3-D work. An isometric drawing is not true 3-D.

The CAD command ISOPLANE allows one to easily draw an object at 30 degree angles needed fo isometric drawings.

Lesson 3-3 Working in 3 Dimensions

We are used to just using 2 axis. when working in 3 dimensions a third axis is introduced, the z-axis. the axis represent the height, length, and depth of an object.


Lesson 3-4 Viewing 3-D Objects

In CAD you can use view ports to to more easily see all the sides of your object. there are viewports for the x axis, y axis, and z axis.

Lesson 3-5 Basic Wire Frame Models

Wireframes are the simplest way to display 3D objects. They are like a skeleton of the object, and allow you to look through and see other edges.
Lesson 3-6 Line Thickness

This is the terminology from the Free CAD Lesson Intro to 3D

3D Auto CAD

Terminology

2-D - A concept of displaying real-world objects on a flat surface showing only height and width. This system uses only the X and Y axes.

3-D - A way of displaying real-world object in a more natural way by adding depth to the height and width. This system uses the X Y and Z axes.

Boolean Operations

Commands that allow you to add, subtract or intersect solid objects in AutoCAD.

Complex surface - Generally a curved surface. Examples: car fender, landscape contour.

Elevation - The difference between an object being at zero on the Z-axis and the height that it is above zero.

Extrude - The extrude command raises the shape of a 2D outline into a 3D solid. For example, a circle would be extruded into a cylinder.

Face - The simplest true 3-D surface.

Facet - A three or four sided polygon that represents a piece (or section) of a 3-D surface.

Hidden line removal - A way of hiding lines that would not be visible if you were viewing the actual object you have drawn in AutoCAD. (Command: HIDE)

Isometric Drawing

A simple way of achieving a '3-D' appearance using 2-D drawing methods.

Plan View - Also known as the top view, a plan view looks directly down the WCS Z-axis to the X-Y axis.

Primitive

A basic solid building block. Examples would be boxes, cones, cylinders.

Region

A 2-D area consisting of lines, arcs, etc.

Rendering

A complex way of adding photo-realistic qualities to a 3-D model you have created.

Shading - A quick way of adding color to a 3-D object you have drawn. (Command: SHADE)

Solid Model - A 3-D model creating using solid 'building blocks'. This is the most accurate way of representing real-world objects in CAD.

Surface Model - A 3-D model defined by surfaces. The surface consists of polygons. (See facets.)

Thickness

A property of lines and other objects that gives them a 3-D like appearance.

USC

The user co-ordinate system. This is defined by the person drawing to have easier access to portions of a 3-D model.

View

A particular view of the object you have created.

Viewport

A window into your drawing showing a particular view. You can have several viewports on your screen. Different from the viewports used in plotting.

Wireframe Model

A 3-D shape that is defined by lines and curves. A skeletal representation. Hidden line removal is not possible with this model.

Z-axis

The third axis that defines the depth.

don't look at that last post!!

that last post was a failure, maybe this is better!

Isoplane Drawing

today i started by completing the Isoplane drawing. it makes drawing in isometric much easier.