Print Dimensioning - 2 Flashcards
What is the first view you should choose when creating a multi view drawing?
The front view, because it is the most detailed side.
What should you do if the front view is not the most revealing?
Change the front view to any side with the most information.
If the front view is not obvious, what side should you chose?
Select the view you think is best.
What other views are needed when you have selected the front view? Explain why.
The Top or Right views because the front view only shows width and height. Not the depth.
After selecting the view that shows depth, what view should you choose next?
The view that shows the most features that the front view doesn’t show.
Lets say we have an L-Shaped Bracket, and we have the front and top view show all principal dimensions, do we need to show another view? and why?
Yes because the “L” view was not shown on either view which shows more information.
What type of viewed drawing is commonly used to make a print of an object less complex like a six-view drawing does.
A Three-View Drawing
Lets say you have a rod, how many views would you need?
Only two.
Some objects only need one-view like rings, what else shows information besides views?
A note.
What are two-view drawings for?
They are used for objects that require to show more detail like symmetrical cylindrical objects.
What is the function of a dimension on a print?
The function is of dimensions is to specify the size and location of features on an object.
What are the three dimensions?
Height, Width, Depth.
What do dimensions also indicate on a print dimension?
Radii and Diameter of rounded features.
What are four features used indicate dimensions?
Extension lines, Dimension Lines, Dimension Units, and Leader lines
What are Extension lines?
Extensions are the points used to create the dimension.
What should you do when drawing Extension lines?
They should be drawn as thin solid lines extending from the edges of the object lines.
What should an Extension line have so it isn’t mistaken to be an object line?
A small gap.
If an Extension line crosses an object line, do you break the line to create another small gap?
The line should not break if there is an object line in its path.
What are Dimension lines?
Dimension lines are an indication to the extension lines that define the dimension.
What shape is used to determine a Dimension line? What do they indicate?
An Arrowhead. They point towards the extension lines.
What if the extension lines are too small of a space? Where do you place the Dimension lines?
On the outside of the extension lines pointing inwards.
What are Dimension Units?
Dimension units specify the measured value of an object feature. Given by a number and a unit of measure. (Ex. inches)
To avoid abbreviations in dimension units, where should you place your unit of measure?
You should put a note in the title block of the drawing saying: UNLESS OTHERWISE SPECIFIED, ALL DIMENSIONS ARE [INCHES, MILLIMETERS, ETC.].
What is a Leader?
A leader attaches a note or a dimension to an object.
What does a Leader line consist of?
Two lines and an arrowhead.
How do you sketch a leader line?
With one horizontal line, one diagonal line at the direction of the object you want to add a note, and the arrowhead at the end of the diagonal line.
What should a leader line always be doing
Never break a leader line, should always be drawn on the outside of a circle, arrow needs to be touching the circle.
What are the two systems of measurement?
US Customary System, and the SI Metric System.
What does the US Customary System consist of?
Inches, Feet, Miles, Yards.
What does the SI Metric System consist of?
Millimeter, Centimeter, Meter, Kilometer.
What are two types of circular features you will see dimensioned on a print?
Circles and arcs.
What measurement is used on a circle? What symbol?
Diameter, with the symbol Ø.
What is an arc used for? What letter does it use to refer to radius
Used to represent a radius of a part, with the letter R to represent it.
What are three types of angular features you will see dimensioned on a print?
Angles, Chamfers, and Tapers.
What are Angles?
Angles are dimensioned by giving the measurement in degrees between adjacent surfaces.
What type of lines are used for Angles?
Extension lines and Dimensions/Dimension lines.
What are Chamfers?
A chamfer is a special type of angle created to remove the sharp edge that results from a 90 degree angle.
What are Tapers?
A taper is a conical feature on a shaft or a hole.
What are Tapers used for?
Tapers are used for aligning parts during assembly, or to provide a means for connecting parts.
What are the six rules to show the dimensions of an object on a print?
- Objects are completely dimensioned.
- Objects are not over dimensioned. (Unneeded Dimensions)
- Dimensions are shown in the view that most clearly show the feature.
- Hidden lines are not to be dimensioned.
- Dimensions must be provided in a Usable Manner.
- Dimensions must be provided in a Readable Manner.
What is Dual Dimensioning?
Dual Dimensioning is when you provide dimensions on the print in more than one unit of measurement. Such as US Customary & Metric system.
What are two ways to represent Dual Dimensioning?
- One unit is put on the top middle of the Leader line and the other unit right below it.
- The second way to do it is to use slashes to separate both units. (not measurements)
What do you do when selecting to use slashes for Dual Dimensioning?
A note needs to be added to the title block about the units of measurements used.
What is First Angle Projection?
First Angle Projection shows views as if they were projected through the object onto the inside of a solid box.
What are the differences of First Angle Projection than from Third Angle Projection?
The First Angle Projection has the top side directly below of the front view. Right side is directly to the left of the front view. Left side is drawn directly to the right of the front view. The rear side is drawn directly right of the right side view. Lastly, the bottom side is drawn above the front view.
Study the First Angle Projection symbol
Ok ☺️
