Parallel Line Development Flashcards
What is the parallel line development method based on?
Plotting lines parallel to each other on the surface of an object
This method is used to develop a pattern for the object.
What types of objects are commonly fabricated using the parallel line development method?
- Round elbows
- Rain gutters
- Cornice mouldings
- Chutes
- Canopies
- Pipe tees
These objects typically have a constant cross-section.
What is the simplest type of pattern development method?
Parallel line development
It is considered the simplest concept to understand among various pattern development methods.
What basic objects utilize the principles of parallel line development?
- Basic elbows
- Roof jacks
These help in understanding how all views and patterns are connected.
Can parallel line development be applied to more complicated objects?
Yes
More complicated objects may require additional steps, but the basic principles remain the same.
What types of round duct fittings are developed using parallel line development?
- Round elbows of any angle
- Any number of pieces
- Round offsets
The method is versatile for constructing various configurations.
True or False: Patterns for non-round objects cannot be developed using parallel line development.
False
The same process can be used for square, hexagon, or octagonal elbows and offsets.
Fill in the blank: The parallel line development method is often used for objects with a _______.
constant cross-section
This characteristic is essential for the applicability of the method.
What is parallel line development?
A process of developing patterns for objects with a constant cross-section.
What is required to develop the pattern in parallel line development?
Two or more views of the object and measurements taken from each view.
What are element lines in parallel line development?
Lines used for development, drawn on the surface of the object in the elevation view at their true length.
What does the elevation view represent?
What the object would look like if viewed from the side.
In the elevation view, how are element lines represented?
Generally true length.
What does the plan view represent?
How the object would look from above or below.
How are element lines represented in the plan view?
As points only.
What is the purpose of transferring element lines to the pattern?
To provide the details necessary to complete the pattern.
Fill in the blank: The element lines in the elevation view are drawn _______.
[at their true length]
True or False: The perimeter of the object is usually detailed in the elevation view.
False.
What is a step-off distance?
A distance on the stretchout line representing the distance between element points as seen in the plan view.
Step-off distances are calculated along the stretchout line for accuracy, especially when special features require extra element lines or points.
When are step-off distances particularly useful?
When an accurate calculation is difficult, often due to special features requiring extra element lines or points.
The distance from the extra point is stepped-off from one of the elements on the plan view.
What are primes in parallel line pattern development?
Names used to identify extra element points related to another point by adding an apostrophe to the letter or number.
For example, 3 and 3’ would be referred to as three and three prime.
How should primes be used in relation to element lines?
Primes should indicate different ends of a line but should avoid naming the entire line with primes, instead using a single label.
For example, the entire line should be called 3, while 3’ can indicate a special point related to 3.
Fill in the blank: A step-off distance is usually calculated and measured along the _______.
[stretchout line]
True or False: Primes can be used to indicate changes in direction in parallel line development.
True
