What must remain constant in dimensioning elements?
The letter & numeral size.
All arrow heads must touch the extension line.
All arrowheads must touch the extension lines.
What does the title block contain?
- Name of drafts person
- Name of checker
- Date drawn
- Company logo/name
- ISO Projection symbol
- Tolerance block
- Name of part drawing
The title block is essential for identifying the drawing and its contributors.
What do plane lines indicate in a sectional view?
Where the sectional views come from. Using arrow lines with solid for simple parts, dashed (— — —) or small & long dashed lines (- — - — -) for complicated parts.
This is crucial for understanding the orientation of the section.
What is the purpose of break lines?
Allow symmetrical shapes to be drawn in less space
Break lines simplify the representation of complex shapes.
What does symmetry show in a drawing?
That a part is the same on either side of the line
Symmetry is important for design consistency.
In structural steel with the W shape, what variations can be made to change weight?
- Flange width
- Flange thickness
- Web thickness
“W-shaped” structural steel aka a wide flange beam is actually shaped like an “H” or an “I” with parallel inner flange surfaces.
W12x30, indicates depth (approx. 12”) and weight (30 lbs/ft)
What is the front view considered in all cases?
The key view!
The front view provides a primary perspective of the object.
Name the two types of orthographic projection.
- First angle
- Third angle
These projections determine how views are arranged relative to the object.
What happens in first angle projection?
The orientation of the object is inverted
This affects how the views are represented on the drawing.
What is a full sectional view?
The cutting plane is straight and goes completely through the workpiece
This view provides a complete internal representation.
What is a half sectional view?
The cutting plane line goes through only half of the workpiece
This shows both the inside and outside of the workpiece.
What is a removed sectional view?
Does not use a cutting plane line; shows the cross-sectional shape
A centerline is used to indicate where the section was taken.
