How to make a spur gear using AutoCAD

You can make a spur gear using AutoCAD following this simple tutorial Step 1: Lunch AutoCAD.

• Step 2: Draw 2 circles of 50mm radius and 35mm radius respectively To draw circle in the command line type circle, or c and press enter Choose r for radius and enter 50 for the first circle repeat again for the second circle.

 • Step 3: Make the gear tooth spaces profile

. • Step 4: Trim the circles side ways.

 • Step 5 Now enter "bo" command. It will show the boundary creation dialogue. Click Pick point. This command is going to be used for creating the polyline.

 • Step 6: Click inside the region and then press enter.

 • Step 7 Now we have the polyline created. Remember bo command doesn't join the lines but creates a polyline bounded by a region. Therefore the lines and arcs are also there.

 • Step 8 Make a circle of 50mm radius.

 • Step 9 Extrude it by 15mm.

 • Step 10 Now extrude the tooth polyline by 25mm.

 • Step 11 Array>>polar array>> and select the tooth profile extruded to array and the center point be origin and no. of items let be 12. Click OK

 • Step 12 Now subtract the tooth profile arrayed from the cylinderical disc and we have the gear body.

CHAPTER 3: Drawing Your First Objects in Autocad

Introduction

This tutorial is designed to show you how all of the AutoCAD Draw commands work. If you just need information quickly, use the QuickFind toolbar below to go straight to the command you want or select a topic from the contents list above. Not all of the Draw commands that appear on the Draw toolbar are covered in this tutorial. Blocks, Hatch and Text for example are all tutorial topics in their own right!

The Draw commands can be used to create new objects such as lines and circles. Most AutoCAD drawings are composed purely and simply from these basic components. A good understanding of the Draw commands is fundamental to the efficient use of AutoCAD.

The sections below cover the most frequently used Draw commands such as Line, Polyline and Circle as well as the more advanced commands like Multiline and Multiline Style.  As a newcomer to AutoCAD, you may wish to skip the more advanced commands in order to properly master the basics. You can always return to this tutorial in the future when you are more confident.

In common with most AutoCAD commands, the Draw commands can be started in a number of ways. Command names or short-cuts can be entered at the keyboard, commands can be started from the Draw pull-down menu, shown on the right or from the Draw toolbar. The method you use is dependent upon the type of work you are doing and how experienced a user you are. Don't worry too much about this, just use whatever method feels easiest or most convenient at the time. Your drawing technique will improve over time and with experience so don't expect to be working very quickly at first.

If you are working with the pull-down menus, it is worth considering the visual syntax that is common to all pull-downs used in the Windows operating system. For example, a small arrow like so " " next to a menu item means that the item leads to a sub-menu that may contain other commands or command options. An ellipsis, "…" after a menu item means that the item displays a dialogue box. These little visual clues will help you to work more effectively with menus because they tell you what to expect and help to avoid surprises for the newcomer.

Before we start any drawing it is mandatory and professionally that we must set up a layer for the drawiong