Drafting Symbols

AutoCAD and Its Applications

REFERENCE M AT E R I A L S

B A S I C S S t u d e n t We b S i t e

Drafting Symbols Symbols provide a “common language” for drafters all over the world. However, symbols are meaningful only if they are drawn according to relevant standards or conventions. This document describes and illustrates common dimensioning, GD&T, architectural, piping, and electrical symbols.

Recommended ASME Dimensioning Symbols The size of dimensioning symbols is consistent with text height. In the following illustration, H = text height. 60° 1.5H

H Diameter

Spherical Radius

Radius

Spherical Diameter

Controlled Radius

1.5H

Places or By

90° 2H

H 2

H

H

Symmetrical Shape

H

0.8H

Counterbore

Spotface

H Countersink

Square Shape

H 1.5H

0.3H H H

0.6H

0.3H Arc Length

1.5H

60° Depth or Deep

Dimension Origin

Reference

0.5H 30° 15°

2H

H

H

1.5H

0.5H Taper

Slope

All Around

All Over

H = Letter height

Copyright by Goodheart-Willcox Co., Inc.

Drafting Symbols, page 1




Geometric Dimensioning and Tolerancing Symbols You can create a library of GD&T symbols, use AutoCAD GD&T tools, or use an AutoCAD GD&T font to insert symbols as text. The following tables show examples of GD&T symbols. For complete coverage of GD&T, refer to Geometric Dimensioning and Tolerancing by David A. Madsen, published by Goodheart-Willcox Company, Inc. 2H

2H

H

Any needed length 60° H

H = Letter height Datum Feature Symbols

Target area size, when used 0.8H

3.5H 0.3H Target number

Datum

60°

H = Letter height Datum Target Symbol

Movable Datum Target Symbol Datum Target Symbols





B A S I C S S t u d e n t We b S i t e Straightness Form

Flatness Circularity Cylindricity

Profile

Profile of a Line Profile of a Surface Position

Location

Concentricity Symmetry

Parallelism Orientation

Perpendicularity Angularity

Runout

or

Circular Runout

or

Total Runout

Geometric Characteristic Symbols

1.5H 0.8H H = Letter height Material Condition and Material Boundary Style

2H minimum

2H minimum

H

2H H = Letter height Feature Control Frame Symbol





B A S I C S S t u d e n t We b S i t e 2H

H H = Letter height Basic Dimension Symbol

2X 0.4H

0.8H

1.5H Free State

Tangent Plane

Projected Tolerance Zone

Independency

Unequally Disposed Profile

3H 0.8H

0.6H

3X 1.5H Translation

Between

2.5H

2.5H

1.5H

0.8H

0.8H

1.5H 30°

30° Statistical Tolerance

Continuous Feature H = Letter height

Additional GD&T Symbols






To draw GD&T symbols as text, create a style using the gdt.shx, GDT_IV25, or GDT_IV50 font. Then use the lowercase alphabet to type the symbols. The following table shows the symbol produced by each lowercase letter. Lowercase Letter Symbol Produced a b c d e f g h i j k l m n o p q r s t u v w x y z Copyright by Goodheart-Willcox Co., Inc.





Architectural Symbols The following table show basic examples of architectural drafting symbols. Common Architectural Symbols

Exterior Door

Toilet

Water Heater

Wall Hung Toilet Interior Door Shower Pocket Door

Urinal

Bifold Door Oval Vanity Sink Bipass Door Window

Rectangular Vanity Sink

Lighting Outlet Recessed Lighting Outlet

Shower w/ Seat

Tub Single Kitchen

Wall Lighting Outlet Washer/Dryer

Fluorescent Light Fixture Single Receptacle Outlet Duplex Convenience Outlet Triplex Receptacle Outlet Special Outlet Floor Single Receptacle Outlet Floor Duplex Receptacle Outlet

Double Kitchen 220V Outlet Weatherproof Outlet Thermostat

Refrigerator

Doorbell Fan Hanger Receptacle

Single Pole Switch

Clock Hanger Receptacle

3-Way Switch

TV Outlet


Range

Fan

Conduit





Piping Symbols The following table show basic examples of piping drawing symbols. Single-Line Piping Symbols Screwed Name

Left Side

Front

Buttwelded Right Side

Left Side

Front

Right Side

90° Elbow

45° Elbow

Tee

45° Lateral

Cross

Cap Concentric Reducer Eccentric Reducer Union Coupling






Electronic Symbols The following table show basic examples of electronic drawing symbols. Common Symbols for Electrical Diagrams Microphone

Capacitor, Polarized Amplifier Circuit Breaker

Twin Triode Using Elongated Envelope

Antenna, General

Receiver, Earphone

Resistor, General Ground Voltage Regulator, also, Glow Lamp

Antenna, Dipole

Resistor, Adjustable Chassis Ground

Antenna, Dipole

Connectors, Jack and Plug

Phototube

Resistor, Variable

Inductor, Winding, Reactor, General Antenna, Counterpoise

Transformer, General

Engaged Connectors Magnetic Core Inductor

Battery, Long Line Positive Adjustable Inductor

Multicell Battery

Triode with Directly Heated Cathode and Envelope Connection to Base Terminal

Ballast Lamp Shielded Transformer, Magnetic Core

Capacitor, General

Capacitor, Variable

Transformer, Magnetic Core

Fluorescent, 2-Terminal Lamp Pentode Using Elongated Envelope


Incandescent Lamp

Auto-Transformer, Adjustable
