## Tuesday, April 28, 2009

Lesson 3-6 Line Thickness

Line thickness is the height of a line, not the width which it is often confused with. It is used to give the line a 3-D effect.Lesson 3-7 Regions and 3-D surfaces

You can start working in true 3-D with the Region, Extrude, and Face Command.
Region specifies an area, and Extrude makes a shape 3-D from a 2-D closed shape. (It pulls it out)

Lesson 3-7a Extruding to Create 3-D objectsUsing Extrude from the last lesson you can extrude to a path, or you can taper it. The image above uses both, the circle is extruded to a path and it is tapered.

Lesson 3-8 Revolved Objects

Resurf rotates a line along a path to create a surface around an axis. Revolve creates a solid object from a line along a path.Lesson 3-9 Adding Materials

Lesson 3-10 Primitive Solids

A primitive solid is a simple object that you can use to work with in 3D. AutoCAD has some basic 3D shape commands at your disposal. From these basic primitives, you can start building your 3D models.

 SHAPE COMMAND ICON DESCRIPTION BOX BOX Creates a solid box after you provide 2 opposite corners. SPHERE SPHERE Creates a solid sphere from a center point and radius. CYLINDER CYLINDER Creates a straight cylinder from a center point, radius and height. CONE CONE Creates a tapered cone from a center point, radius and height. WEDGE WEDGE Creates a triangular wedge from 2 opposite points. TORUS TORUS Creates a torus (donut shape) based on center point, radius and tube radius. POLYSOLID PSOLID Draws a solid object with width and height as would draw a polyline.

Lesson 3-11 Boolean Operations

 COMMAND INPUT ICON DESCRIPTION UNION (Boolean) UNI Joins two or more solids into creating one based on the total geometry of all. SUBTRACT (Boolean) SU Subtracts one or more solids from another creating a solid based on the remaining geometry. INTERSECT (Boolean) IN Creates a single solid from one more solids based on the intersected geometry. EXTRUDE FACE SOLID EDIT Allows you to increase the size of a solid by extruding out one of its faces. SLICE SLICE none Slices a solid along a cutting plane. 3D ALIGN 3DALIGN Aligns 2 3D Objects in 3D space.

Lesson 3-12 The User Co-ordinate System

It allows you to change the plane you are drawing on so that you can add more detail
Lesson 3-13 Mapping Materials

Involves changing the size of the image (material) and the orientation of it so that it makes the most sense and looks presentable.

 COMMAND OR INPUT ICON DESCRIPTION MATERIALMAP None Enter this on the command line to select mapping options via keyboard. Planar Mapping Maps individual faces of an object. Box Mapping Maps any solid object with controls for width, depth and height as well as rotation on all sides. Sphere Mapping Allows you to map any solid object, but uses rotation only. Cylinder mapping Maps a solid object with height and rotation only.

Lesson 3-14 Creating New Materials

Sometimes you need to create your own material images because Auto CAD does not have them already.

Lesson 3-15
Lesson 3-16
Lesson 3-17

All involve using Auto CAD 3-D they contain extra topics or tools through a project, of building a house.

## Monday, April 27, 2009

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

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.

## Thursday, April 23, 2009

### 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.

## Thursday, April 2, 2009

### Jukebox from Mohawk CAD Competition

This is is the jukebox drawing from Mohawk College. It was fairly easy to finish there were only a few sections that were difficult to do. In total it took about a class for me to finish, just short of a class.