AutoCAD 2D I Module13[1] - Maysaa Nazarmaysaaiat.weebly.com/uploads/5/8/8/3/5883161/autocad_2d_i_modul… · Institute of Applied Technology Fillets Module 13 2 Auto CAD Self-paced

AutoCAD 2D I

Module 13

Fillets

PREPARED BY

IAT Curriculum Unit

Jan 2011

© Institute of Applied Technology, 2011

Institute of Applied Technology

Fillets Module 13 2

Auto CAD Self-paced Learning Modules

AutoCAD 2D

Fillets

Learning Outcomes: When you have completed the module, you will be able to:

1. Describe tangency and fillet. 2. Describe and apply the FILLET command to construct objects that

contain tangent arcs and the LINE command with the aid or the objects snap mode tangent to draw lines tangent to arcs.

Module 13

AutoCAD Geometry Lesson Tangency Part 1

A point of tangency is the theoretical point where a line joins an arc or where two arcs join each other making a smooth transition. A line passing a circle will hit one point on the circle. The point they touch is called the point of tangency. A fillet is a tangent arc. On the right are some examples of fillets.

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Fillets Module 13 3

Tangency Part 1 - Continued

AutoCAD uses the FILLET command to construct fillets. A fillet is a tangent arc. To help you understand the geometry of how a fillet is constructed, study the diagrams below. They show how a tangent arc is constructed between two existing lines. As you work your way through the modules, many other examples will be showing you examples of fillets and tangency.

AutoCAD User “Must Know” No. 13-1

A fillet is a tangent arc. To construct a fillet you use the FILLET command. The rule of thumb to follow is “if the arc you are drawing is tangent to both objects it is connecting to, then use the FILLET command. If the arc is tangent to one or neither of the objects, use the ARC command”.

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Fillets Module 13 4

AutoCAD Command: FILLET The LIMITS command is used to set the limits for the drawing. Command Line Syntax: Command: FILLET or Command: F

2004-2006

Using the FILLET Command

Command: LINE Specify first point: 8,4 Specify next point or [Undo]: @4,0 Specify next point or [Undo]: @-1.3,0 Specify next point or [Close/Undo]: @0,-1.2 Specify next point or [Close/Undo]: @0,1.2 Specify next point or [Close/Undo]: @-1.3,0 Specify next point or [Close/Undo]: @0,-4 Specify next point or [Close/Undo]: C (First construct the outline of the object.) Command: FILLET Current settings: Mode = Trim, Radius = 0.6000 Select first object or [Polyline/Radius/Trim]: R Specify fillet radius<0.6000>: .25 (Set the radius for the fillet.) Select first object or [Polyline/Radius/Trim]: P 1 Specify second point: P 2 (Pick the two lines to insert the fillet between.) Command: FILLET Current settings: Mode = Trim, Radius = 0.2500 (Notice how AutoCAD remembers the fillet radius. It only needs to be changed if the radius change.) Select first object or [Polyline/Radius/Trim]: P 3 Specify second point: P 2 Command:

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Fillets Module 13 5

Object Snap Modes for all Objects

Modes Abbreviations Icon Marker The AutoCAD Object

Tangent

Tan

Using the FILLET Command - Continued

Command: FILLET Current settings: Mode = Trim, Radius = 0.2500 Select first object or [Polyline/Radius/Trim]: R Specify fillet radius<0.6000>: .35 Select first object or [Polyline/Radius/Trim]: P 5 Specify second point: P 6 Command: FILLET Current settings: Mode = Trim, Radius = 0.3500 Select first object or [Polyline/Radius/Trim]: P 7 Specify second point: P 8 Command:

Using the FILLET Command

Command: CIRCLE Specify center point for circle or [3P/2P/Ttr {tan tan radius}]: 6,6 Specify radius of circle or [Diameter]<0.0000>: 2 (This is a construction circle, place it on the construction layer.) Command: CIRCLE Specify center point for circle or [3P/2P/Ttr {tan tan radius}]: @4<90 Specify radius of circle or [Diameter]<2.0000>: 1.5 Command: LINE Specify first point: cen of P1 Specify next point or [Undo]: @5.7<45 Specify next point or [Undo]: (This is a construction line, place it on the construction layer.)

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Fillets Module 13 6

Using the FILLET Command - Continued

Command: CIRCLE Specify center point for circle or [3P/2P/Ttr {tan tan radius}]: end of P2 Specify radius of circle or [Diameter]<1.5000>: 1 (First construct the circle.) Command: LINE Specify first point: tan of P3 Specify next point or [Undo]: tan of P4 (Notice how you have to enter tan to both ends of the line.It is a very common error to forget to enter it at the second end.) Command: LINE Specify first point: tan of P5 Specify next point or [Undo]: tan of P6 Command: LINE Specify first point: tan of P7 Specify next point or [Undo]: tan of P8 Command: LINE Specify first point: tan of P9 Specify next point or [Undo]: tan of P10 Command: FILLET Current settings: Mode = Trim, Radius = 0.0000 Select first object or [Polyline/Radius/Trim]: R Specify fillet radius<0.6000>: 2 Select first object or [Polyline/Radius/Trim]: P11 Specify second object: P12 (After turning the construction layer off, place a fillet between the lines.) Command: FILLET Current settings: Mode = Trim, Radius = 0.2000 Select first object or [Polyline/Radius/Trim]: R Specify fillet radius<0.6000>: 3 Select first object or [Polyline/Radius/Trim]: P13 Specify second object: P14 (Construct a 3 R fillet between the lines at the cottom Of the object.) Command:

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Fillets Module 13 7

AutoCAD User Tip 13-1

If you want to insert an arc at the end of parallel lines, use the FILLET command. Regardless of what radius is currently set, AutoCAD will draw a tangent arc using the distance between the lines as the radius. Command: FILLET Current settings: Mode = Trim, Radius =0.0 (Notice how the radius is set to zero. It can be any size.) Select first object or [Polyline/Radius/Trim]: P1 Specify second object: P2 Command:

AutoCAD User Tip 13-2

By setting the radius of the FILLET command to zero, a fillet Will square off a corner. The Lines can be too short or too long or a combination of the two. See the diagram to the right. Command: FILLET Current settings: Mode = Trim, Radius = 0.6000 Select first object or [Polyline/Radius/Trim]: R Specify fillet radius<0.6000>: 0 Select first object or [Polyline/Radius/Trim]: P1 Specify second object: P2 Command: FILLET Current settings: Mode = Trim, Radius = 0.0000 Select first object or [Polyline/Radius/Trim]: P3 Specify second object: P4 Command: FILLET Current settings: Mode = Trim, Radius = 0.0000 Select first object or [Polyline/Radius/Trim]: P5 Specify second object: P6 (If you are not sure your corners are 100% perfect, it is a good idea to fillet corners with a zero radius to ensure they are.) Command:

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Fillets Module 13 8

AutoCAD User Tip 13-3

If you do not want the objects being filleted to be trimmed, use the no-trim option as shown below. Command: FILLET Current settings: Mode = Trim, Radius = 0.0 Select first object or [Polyline/Radius/Trim]: T Enter Trim mode option [Trim/No Trim]<Trim>: N (First, set the fillet to no-trim.) Select first object or [Polyline/Radius/Trim]: R Specify fillet radius<0.0000>: 1 (Then set the radius.) Select first object or [Polyline/Radius/Trim]: P1 Specify second object: P2 Command: FILLET Current settings: Mode = Trim, Radius = 1.0 Select first object or [Polyline/Radius/Trim]: R Specify fillet radius<0.0000>: .25 Select first object or [Polyline/Radius/Trim]: P3 Specify second object: P4 Command: FILLET (Notice what happens when the lines are shorter than the filleted arc.) Command:

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Fillets Module 13 9

Instruction:

1. Setup the layers using the Layering Scheme above. 2. Draw the object shown below. 3. Check your drawing with the key.

Lab Exercise 13-1 Time Allotted: 30 min.

Drawing Specifications Name Template Units Text Style FontAutoCAD 2D Lab 13-1 Module Template A Inches N/A N/A

Note: Color, Linetype and Lineweight are all ‘ByLayer’ unless otherwise instructed.

Layering Scheme

Objects on Layer Name Color Linetype Lineweight

Construction Objects Construction 253 N/A N/A

All Objects Object Red N/A N/A

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Fillets Module 13 10

Instruction:

1. Setup the layers using the Layering Scheme above. 2. Draw the object shown below. 3. Check your drawing with the key.

Note: Draw this line at any length but at the correct angle. Then draw a vertical line from the end of the arc above at any length but in the – Y direction. The FILLET command will automatically trim or extend the two lines.

Lab Exercise 13-2 Time Allotted: 30 min.

Drawing Specifications Name Template Units Text Style FontAutoCAD 2D Lab 13-2 Module Template A4 Millimeter N/A N/A

Note: Color, Linetype and Lineweight are all ‘ByLayer’ unless otherwise instructed.

Layering Scheme

Objects on Layer Name Color Linetype Lineweight

Construction Objects Construction 253 N/A N/A

All Objects Object Red N/A N/A