This document provides an overview of blueprint reading. It discusses what blueprints are and how they are used to convey engineering and architectural design drawings. It then explains how to interpret various components of blueprints, such as title blocks, revision blocks, notes, legends, views, scales, and grid systems. The document also outlines different types of lines used in blueprints and various symbols and terminology. Examples of engineering, architectural, mechanical, and electrical blueprints are presented.

1. ENGINEERING / TECHNICAL DRAWING
TUTOR: NNANNA, OBIABUCHI MARTIN
TOPIC:BLUE PRINT READING
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2. BLUE PRINT READING
A. INTRODUTION:
Blueprints are 2-dimensional architectural and
engineering design drawings that indicate the size of a
planned building and engineering works, the materials to
be used in its construction, and the placement of its
features.[1]
Blueprints (prints) are copies of mechanical or
other types of technical drawings. The term blueprint
reading means interpreting ideas expressed by others on
drawings, whether or not the drawings are actually
blueprints.[2]
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3. HOW TO READ AND INTERPRET BLUEPRINTS[1]
1. Read the title block
2. Read the revision block. Any time changes to a
building/system/component are made; the drawing has to
be redrafted. Those changes are listed here.
3. Read the notes and legend.
In addition to the standard scale, grid, and lines, blueprints
are often comprised of other symbols and numbers.
4. Determine the view. With 2D blueprints, there are three
common perspectives: plan, elevation, and section.
5. Establish the scale in your mind. Blueprints are scaled
down representations of things like houses, underground
piping, and power line.
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4. B. HOW TO READAND INTERPRET BLUE-PRINTS[1]
6. Inspect the grid system. Along the horizontal and
vertical edges of a blueprint, drawers often fix a simple grid
system with numbers on one axis and letters on the other.
7. Locate any doors and windows. On blueprints, doors
look like larger gaps between walls. There will also be a
curved line with a mock door extended in or out of the door
frame.
8. Identify any appliances. Fridges, toilets, sinks, ovens,
stove-tops burners, and the like will be represented by
simplistic representations that are readily recognizable.
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5. C. READING LINES
Lines are the language of blueprints. Lines often represent
walls, door frames, and appliance exteriors; however they
have many other purposes and are the primary
characteristic of planned drawings.
The types of basic lines are as follows:
• Object Line
• Hidden Line
• Center Line
• Extension and Dimension Line
• Cutting Plane Lines
• Section Line
• Break Lines
• Phantom Line
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.
Fig.6.1-Use of standard line[2]

7. D. LINE STANDARDS[2]
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8. D. LINE STANDARDS[2]
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9. E. SYMBOLS AND TERMINOLOGY USED IN
ENGINEERING DRAWING[3]
i. Three Types of Thread Representations
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10. ii. Finish Symbols
iii. Fillets and Rounds
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11. iv. Machine Slots
iv. Countersink
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12. vi. Counter bore
vii. Spot Face
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13. viii. Lug
ix. Chamfer
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x.Boss

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F. BLUE-PRINT READING FOR ENGINEERING
WORKS
The components of blue-print for engineering drawings
include the following:
• a) Plan
• b) Elevation( Front elevation, Left side Elevation, Right
side Elevation and Rear Elevation)
• c) Section
• d) An assembly or subassembly drawing showing all
the standard and nonstandard parts in a single drawing.
• e) A bill of materials (BOM)
• f) Etc.

15. • EXAMPLE OF ENGINERRING BLUE-PRINT
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16. • BLUE-PRINT READING FOR BUILDING WORKS
The components of blue-print for building drawings include
the following drawings;
a) Plan
b) Elevation( Front elevation, Left side Elevation, Right side
Elevation and Rear Elevation)
c) Roof plan
d) Site-plan
e) Section
f) Electrical drawing
g) Mechanical drawing
h) Etc.
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17. • EXAMPLE A: Architectural Drawing
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25. • EXAMPLE B: Mechanical Drawings
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• EXAMPLE C: Electrical Drawings

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• ELECTRICAL LEGENDS

31. REFERENCE MATERIALS
1. Wikihow
2. Naval Education and Training Professional
Development and Technology Center. 14040 (1998).
Blueprint Reading and Sketching. 6490 Saufley Field
Rd,Pensacola, Fl 32509-5237
3. AIDT- Blueprint Reading - 10/22/2009
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32. STAY SAFE
AND
THANKS
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