Simple Layout ( 110102c) Flashcards
What are 5 methods of common layout types in pattern development?
Simple layout
Parallel line development
Radial line development
Triangular development
Rollation development
What is a simple layout?
Patterns drawn directly onto metal without using any orthographic views
What is parallel line development?
Patterns that use a number of straight lines to create a pattern
What is triangulation?
A method of pattern development used to develop patterns for irregular objects
What is radial line development?
Objects that have a main apex point that the pattern is then developed from
What is a rollational development?
The use of a pattern that has been created and is simply rolled onto the new sheet metal
What is stretchout?
The distance around the duct (perimeter)
What is the formula for calculating the stretch out?
2 (width) plus 2 (diameter)
How are brake lines marked?
With the capital x and then marked up or down with the desired angle
What 2 measurements required before laying out a piece of pipe?
Diameter of the pipe
Length of the pipe
What is the formula for pipe stretchout?
(3.14) x ( diameter of pipe) = stretchout
How can raw edge connection be fastened?
By welding the seam
How wide is a slip cleat or s cleat?
1 inch
How wide is a drive cleat?
1 1/8 or 1.125”
What are the slip and drive allowances?
1/2 on square and rectangle
1 on round and radius fittings
What is another name for hammerlock seam?
Tap in
What is the allowance for a hammerlock?
Commonly we use a 3/4 allowance 3 (w) depending on the size of the application
What are the pittsburgh allowances for female and male?
Female 15/16 24mm
Male 1/4 5mm straight fittings and 3/16 for curved
Where are the female pittsburgh seam placed?
On the short side of the fitting
When do we develop a gross pattern?
When we have to add allowances to the net pattern
What angle do we Notch at?
30 degree
What is a standing drive connection also known as?
Cp connection
What is needed on slip and drive connections?
Proper allowances and proper notching
What seem is commonly used for lighter gauge rectangular duct?
Button lock
What are 3 measurements required when laying out the net pattern for a length of rectangular duct?
Duct width
Duct depth
Duct length
What 2 measurements are required before to lay out the net pattern for a round pipe?
Diameter of the pipe
Length of the pipe
What is a hammer lock used for?
To join a smaller rectangular duct to a larger piece like in a pto
What is the most commonly used lock in the sheet metal trade?
Pittsburgh lock
But in real life Pittsburgh for commercial button lock for residential
What is a cut list?
A list of pieces that will be cut at the shear
What are used to join individual pieces of duct or fittings together?
Duct connections
What type of pattern development is used for duct and pipe?
Simple layout
What dimensions are required to layout the net pattern for a length of rectangular duct?
Duct width
Duct depth
Duct length
What is the stretch out of a pattern?
The distance around the Duct
The duct openings should be marked out along the baseline true or false?
True
The length of the duct should be measured from the baseline and drawn parallel to it true or false
True
Brake lines in some cases become the corners of the duct once it is folded and should be marked out on the inside whenever possible true or false
True
What is not an example of a duct connection.
Raw edge connection
Groove seam
Standing drive connection
Hammerlock
Groove seam
Raw edge connection requires that no allowance is added to the completed pattern true or false
True
How many different cleats does the slip and drive connection use?
2
Standing drive connections are primarily used on?
Larger ductwork
Duct seams are used to hold the duct together true or false
True
The female portion of a Pittsburgh is placed on the shorter side of the duct because of the extra stiffness it provides true or false
True
What are duct connections and seam allowances?
Material that is added to a net pattern
What is notching?
Removal of excess material not needed for fabrication
When are object lines and labeling added to a pattern?
Once the gross pattern is complete
Calculating and creating a cut list will save time and material true or false
True
On transitional fittings such as a pto 1 inch of straight material is required in order to allow for the s cleat to be installed true or false
True
