Flat Rectangular AandB+ Roof Jacks Flashcards
The circumference rule is flexible and can be used as a guide for __________ curves.
Irregular curves
What is commonly used as a right angle or straight edge in a shop?
Framing square
What are protractors used for?
To measure and develop various angles
What is preferred to use for marking break lines and cut lines on metal
Felt markers
What helps save material and time during fitting fabrication
A Cut list
Growth allowance for fittings is typically removed by _________inch per joint
1/16”th
What is used to scribe lines parallel to the edge of a sheet of metal?
The Marking Gauge
What is used to scribe arcs larger than you can with dividers?
Trammel points out that
Before you develop a pattern, ensure the material is:
Cut to size and square
Flat rectangular fittings typically consist of:
Cheeks and wrappers/runners
Adjusting the __________ pressure ensures the material is clamped firmly but not deformed
Clamp pressure
What is used to form allowances on curved cheeks of light gauged metal?
A Power flanger
Cross-breaking is done to add ______ to large flat surfaces of metal
Stiffness
Converging angles and allowances must often be formed by what with pliers?
By Hand
What does a standing drive joint provide?
Provides additional rigidity to the duct
What duct connection simplifies fitting assembly and provides more rigidity?
A proprietary duct connection
What is used to open S cleats before installing them
Screw driver
Tacking a seam means:
Folding down the flange in intervals so it doesn’t come apart
Properly finished seam shows what about the fabricator?
Professionalism
The assembly of what fitting begins at the crotch for proper alignment
The Y-Branch fitting
What does the Box-Pan break have that can be adjusted for forming one piece pans?
Adjustable Fingers
To avoid stretching material, fold the flanges in ____
Stages when using a hammer
What machine is used to roll curved runners for duct fittings?
Roll forming machine
The corners of proprietary duct connections are joined with what?
Bolts or Special Clips
What is used to isolate HVAC equipment from ductwork?
Flexible duct connection
What do you do if no specifications are given for installing flexible connections?
SMACNA offers guidelines to help
Stretch out of the material for round flex connector is:
Net pattern stretchout plus 1inch on either side
Fire dampers must be ____ rated and cannot be ___
ULC, Modified
Min and Max a Fire damper sleeve must extend out of the fire wall
3” min and 6” Max
Gauge of metal to be used for a fire damper sleeve is based on the size of the duct and whether the sleeve is made as a what?
Rigid type or has break away connections
The type of breakaway connection is usually set where?
In the Job Specifications
The type of longitudinal seam is most often what?
The same as the ductwork that the fire damper sleeve connects too
Roof jacks are commonly used when:
They need to penetrate the roof membrane
Cylindrical roof jacks are pieces of what?
Round pipe
The 2 most common seams to fasten a round body to a flashing plate are:
Hammerlock or the elbow seam
Conical roof jacks require a different what?
Pattern development
Rectangular roof jack bodies are seamed at:
A corner
Seam locations on sloped roof should avoid:
The up slope part of the jack
Edge at the bottom of the jack is to do what?
Stiffen them
First period sealing will be done with what?
Silicone
The hole in the flashing plate for a sloped jack will be:
Elliptical
Conical cap shape is
Round
The support legs should be mounted ____ to the cap
Perpendicular
Support legs need tabs that bend at what angle towards the peak of the cap?
90 degrees
Minimum edge distance for mechanical fasteners is what?
2 times the fastener diameter
Lap seam allowance must be notched with a ___ of angle notch?
Transfer
The body requires how many fasteners to keep the cap from twisting?
Two fasteners
Roof jack body seam should be sealed how much of its length?
2 thirds of its length
