Title: Computer Aided Design (CAD)
1Computer Aided Design(CAD)
- Engineering Drawing Standards - BS308
2Orthographic Projection
3Orthographic Projection
4Orthographic Projection
5SOME TECHNICAL TERMS (page 1)
6SOME TECHNICAL TERMS (page 1)
CAN YOU DETERMINE THE PROJECTION SYSTEM USED
(first or third angle) CAN YOU IDENTIFY THE
TYPES OF HOLES ABOVE
7Projection Symbol How to Draw
8COMMON LINE TYPES (page 5)
- 1. Continuous Thick (0.5mm) TYPE A
- 2. Continuous Thin (0.25mm) TYPE B
- 3. Dashed Thin (0.25mm) TYPE E
- 4. Chain Thin (0.25mm) TYPE F
9- LINETYPES
- Hidden
- Center
- Hatch
- Outlines
- Text
- Dimension Lines
- Leader Lines
10Leader Lines
- To show where dimensions or notes apply.
- Always end in arrowheads or dots.
- Arrowheads touch and stop on a line
- Dots should be within the outline of the object.
- Long or intersecting leader lines should not be
used.
11General Points on Drafting
- Arrows
- Triangular and Solid
- Length 3 x width
- Arrows on Dimensions -gt 3-5mm Long
- Arrows showing direction of view -gt 7-10mm Long
- Text Height Not less than 3mm.
- Underlining of text is not recommended.
- Notes of a general character to be grouped
together.
12General Points on Drafting
13Commonly Accepted Symbols and Abbreviations
- AF
- ASSY
- CRS
- CL
- CHAM
- CH HD
- CSK
- CSK HD
- CBORE
- CYL
- DIA
- DRG
- EQUI SP
- EXT
- FIG.
- HEX
- HYD
- INSUL
- INT
- LH
- LG
- MATL
- MAX
- MIN
14Commonly Accepted Symbols and Abbreviations
- NO.
- O/D
- PATT NO.
- PCD
- RAD
- R
- REQD
- RH
- RD HD
- SCR
- SH
- SK
- SPEC
- SR
- SFACE
- SQ
15SCREW THREAD - TERMS
16SCREW THREAD - TYPES
17SCREW THREAD - External
18SCREW THREAD - Internal
19SCREW THREAD - Internal
20SECTIONS AND SECTIONAL VIEWS
- (page 12 BS308)
- Hatching is Drawn with Type B (Continuous Thin)
Lines equally spaced at 45º. - Preferably not less than 4mm Apart
- With very small parts never less than 1mm
- On adjacent parts alternate the direction of
Hatching. - Correct Section Line Type F (Chain Thin)
21SECTIONS AND SECTIONAL VIEWS
22SECTIONS AND SECTIONAL VIEWS
23SECTIONS AND SECTIONAL VIEWS
24SECTIONS AND SECTIONAL VIEWS
25SECTIONS AND SECTIONAL VIEWS
- (page 15 BS308)
- PARTS NOT NORMALLY SECTIONED WHEN THE CUTTING
PLANE PASSES LONGITUDINALLY THROUGH - FASTNERS (bolts nuts) SHAFTS RIBS WEBS
SPOKES of WHEELS etc.
26SECTIONS AND SECTIONAL VIEWS
FASTNERS AND SHAFT NOT SECTIONED WEB NOT
SECTONED
27(No Transcript)
28OFFSET SECTIONSECTION IN MORE THAN 1 PLANE
29EXTRA RESOURCE INFORMATION
- DeGarmo E. P. et al. Materials and Processes
in Manufacturing 8th Ed. Maxwell Macmillan
1997
