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Cutting, Holes, Penetrations & Field Fab
167 records, red lane first.
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Accounting for fitting throat when cutting branch
Foreman script · 3rd Year
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Asking before modifying shop-fabricated piece
Foreman script · 3rd Year
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Before core drilling, sleeving, or cutting a deck/wall opening
Foreman script · 3rd Year
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Can duct be notched or squeezed around a storm drain pipe?
Apprentice question · 3rd Year
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Checking if duct is lined before cutting
Foreman script · 3rd Year
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Checking rated wall/shaft before cutting
Foreman script · 4th Year
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Cut edge left where it will tear flex/insulation
Foreman script · 3rd Year
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Deburring cut metal
Foreman script · 3rd Year
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Drilling into embedded utilities or post-tension risk
Field problem · 4th Year
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Duct opening before verifying location
Foreman script · 3rd Year
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Ductwork at Expansion Joints
Field problem · 4th Year
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Ductwork at Expansion Joints
Foreman script · 3rd Year
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Field notch weakens duct corner
Foreman script · 3rd Year
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Field patch creates leakage path
Foreman script · 3rd Year
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Field-fab fix becomes permanent without foreman approval
Foreman script · 3rd Year
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Field-fab transition not matching required airflow direction
Foreman script · 3rd Year
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Floor Openings Do Not Line Up Through the Riser
Foreman script · 2nd Year
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Grinder where sparks are unsafe
Foreman script · 3rd Year
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Hole for takeoff cut too large
Foreman script · 3rd Year
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Hole for takeoff cut too small and fitting forced
Foreman script · 3rd Year
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Hot sparks near insulation or finished surfaces
Foreman script · 3rd Year
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How do I safely drill out spot welds to modify a factory fitting?
Apprentice question · 2nd Year
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I drilled the wrong hole. What do I do before it gets worse?
Field problem · 4th Year
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I need to cut exposed or finished duct
Field problem · 4th Year
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Into embedded utilities or post-tension risk
Foreman script · 3rd Year
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Joint Hardware Is Blocked by Temporary Support or Rigging
Field problem · 4th Year
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Laying out square cut before saw/snips
Foreman script · 3rd Year
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Notch/tab layout on fitting
Foreman script · 3rd Year
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Notching Duct for Structural Conflicts
Field problem · 4th Year
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Notching Duct for Structural Conflicts
Foreman script · 3rd Year
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Opening blocks balancing damper/access
Foreman script · 4th Year
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Penetration sleeve size not verified
Foreman script · 3rd Year
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Ppe for overhead drilling/cutting
Foreman script · 3rd Year
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Protecting finished surfaces from metal shavings
Foreman script · 3rd Year
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Rated wall/shaft before cutting not checked
Field problem · 4th Year
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Rectangular duct cut weakens reinforcement/seam
Foreman script · 3rd Year
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Spiral cut not square
Foreman script · 3rd Year
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Takeoff hole on wrong side of duct
Foreman script · 3rd Year
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Through liner/vapor barrier incorrectly
Foreman script · 3rd Year
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Through reinforcement
Foreman script · 3rd Year
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Too much off ductmate/tdc rail
Foreman script · 3rd Year
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Vacuuming metal chips before handoff
Foreman script · 3rd Year
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What do I do before core drilling, sleeving, or cutting a deck/wall opening?
Field problem · 4th Year
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Wrong tool for cut and damaging duct
Foreman script · 3rd Year
Check first
A 45-degree rectangular fitting arrives with the wrong hand or flat side
Field problem · 2nd Year
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A masonry opening pinches the louver frame out of square
Field problem · 2nd Year
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Branch Weight Is Pulling the Main Out of Square
Field problem · 2nd Year
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Control Sharp Sheet-Metal Edges During Cutting and Handling
Field problem · 2nd Year
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Control Sharp Sheet-Metal Edges During Cutting and Handling
Foreman script · 1st Year
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Cut edge left where it will tear flex/insulation
Field problem · 2nd Year
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Cutting an entire prefab duct run to the wrong length because field dimensions were never verified
Common mistake · 2nd Year
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Cutting duct opening before verifying location
Field problem · 2nd Year
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Cutting on the wrong side of a scribe line and losing dimension
Common mistake · 2nd Year
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Cutting takeoff hole on wrong side of duct
Field problem · 2nd Year
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Cutting through liner/vapor barrier incorrectly
Field problem · 2nd Year
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Cutting through reinforcement
Field problem · 2nd Year
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Cutting too fast on a plasma or snips, creating jagged, uneven edges
Common mistake · 2nd Year
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Cutting too much off Ductmate/TDC rail
Field problem · 2nd Year
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Duct is lined before cutting not checked
Field problem · 2nd Year
Check first
Fabricating a replacement duct section without matching the original gauge and construction class
Common mistake · 2nd Year
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Failing to call a line locator before cutting a ceiling that may have live conduit
Common mistake · 2nd Year
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Field Modification Crosses Reinforcement or an Internal Component
Field problem · 2nd Year
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Field notch weakens duct corner
Field problem · 2nd Year
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Field patch creates leakage path
Field problem · 2nd Year
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Field-Verify Throat, Heel, Centerline, Rise, and Run Before Releasing a Fitting
Field problem · 2nd Year
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Field-fab fix becomes permanent without foreman approval
Field problem · 2nd Year
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Field-fab transition not matching required airflow direction
Field problem · 2nd Year
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Finished surfaces from metal shavings not protected
Field problem · 2nd Year
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Fitting Will Not Rotate Into Place: Check the Insertion Envelope Before Modifying It
Field problem · 2nd Year
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Fitting throat when cutting branch not accounted for
Field problem · 2nd Year
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Hole for takeoff cut too large
Field problem · 2nd Year
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Hole for takeoff cut too small and fitting forced
Field problem · 2nd Year
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Hot sparks near insulation or finished surfaces
Field problem · 2nd Year
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How do I build an end-cap out of flat metal in the field?
Apprentice question · 2nd Year
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How do I correctly rivet a patch plate over an accidental hole in high-pressure duct?
Apprentice question · 2nd Year
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How do I field-cut a tap into the side of a massive low-pressure trunk line?
Apprentice question · 2nd Year
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How do I seal a duct penetration going through a non-rated CMU wall?
Apprentice question · 2nd Year
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How do you lay out a rolling offset without guessing the angle?
Apprentice question · 3rd Year
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I need a gore elbow or advanced flat-pattern formula in the field
Field problem · 2nd Year
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Joint Against a Wall or Beam: Verify Hardware and Tool Access Before Hanging It
Field problem · 2nd Year
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Large Fitting Needs Temporary Internal Bracing During Handling
Field problem · 2nd Year
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Laying out a duct transition using incorrect center-line math
Common mistake · 2nd Year
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Making a 45-degree offset without correctly calculating the setback distance
Common mistake · 2nd Year
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Mirrored Offset: Verify Left-Hand and Right-Hand Before Installation
Field problem · 2nd Year
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Missing PPE for overhead drilling/cutting
Field problem · 2nd Year
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Not asking before modifying shop-fabricated piece
Field problem · 2nd Year
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Not deburring cut metal
Field problem · 2nd Year
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Not laying out square cut before saw/snips
Field problem · 2nd Year
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Not reading the shop drawing before beginning fabrication
Common mistake · 2nd Year
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Not using gloves when handling freshly cut sheet metal edges
Common mistake · 2nd Year
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Not verifying field dimensions before pre-fabricating a large duct run
Common mistake · 2nd Year
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Not wearing safety glasses during cutting, grinding, or drilling
Common mistake · 2nd Year
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Offsets Around Obstacles
Field problem · 2nd Year
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Offsets Around Obstacles
Foreman script · 2nd Year
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Old duct insulation looks unknown or possibly hazardous before I cut it
Field problem · 2nd Year
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Opening blocks balancing damper/access
Field problem · 2nd Year
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Patch Plate Sizing for Duct Modifications
Field problem · 2nd Year
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Patch Plate Sizing for Duct Modifications
Foreman script · 2nd Year
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Penetration sleeve size not verified
Field problem · 2nd Year
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Plan the Final Connection Before the Run Becomes an Impossible Last Joint
Field problem · 2nd Year
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Plenum And Multiple Takeoffs
Field problem · 2nd Year
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Plenum And Multiple Takeoffs
Foreman script · 3rd Year
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Protect Dampers, Sensors, Liner, and Internal Parts During Installation
Field problem · 2nd Year
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Raw Edge, Slip, Collar, or Flange: Connector Ends Do Not Match
Field problem · 2nd Year
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Rectangular duct cut weakens reinforcement/seam
Field problem · 2nd Year
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Reducer or Transition Installed Backward: Verify Airflow and End Sizes Before Final Connection
Field problem · 2nd Year
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Remove Transport Bracing Without Deforming the Fitting
Field problem · 2nd Year
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Replacement Fitting Sketch: Prevent a Second Mirrored or Rotated Remake
Field problem · 2nd Year
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Riser Offset Lands Inside the Floor Zone
Foreman script · 2nd Year
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Round duct runs through a rough CMU wall without a sleeve
Field problem · 2nd Year
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Running a plasma cutter without checking consumables, ruining a large sheet
Common mistake · 2nd Year
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Selecting the wrong interpolation on a CNC plasma for inside vs outside cuts
Common mistake · 2nd Year
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Sheet-Metal Cut and Edge Safety
Field problem · 2nd Year
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Sheet-Metal Cut and Edge Safety
Foreman script · 1st Year
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Should round duct through a block wall have a sleeve?
Apprentice question · 2nd Year
Check first
Spiral cut not square
Field problem · 2nd Year
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Square Throat Elbows And Turning Vanes
Field problem · 2nd Year
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Square Throat Elbows And Turning Vanes
Foreman script · 2nd Year
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Temporary Support While an Awkward Fitting Is Being Connected
Field problem · 2nd Year
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Transition Rotation: Confirm Top, Bottom, and Flat Side Before It Goes Up
Field problem · 2nd Year
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Transition Slope Limits
Field problem · 2nd Year
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Transition Slope Limits
Foreman script · 2nd Year
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Transitioning Around An Obstruction
Field problem · 2nd Year
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Transitioning Around An Obstruction
Foreman script · 3rd Year
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Turning Vanes Were Bent During Transport or Installation
Field problem · 2nd Year
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Using grinder where sparks are unsafe
Field problem · 2nd Year
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Using worn or incorrect snips for the direction of cut (left vs right vs straight)
Common mistake · 2nd Year
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What do I do if a spiral pipe lockseam starts unraveling while cutting?
Field problem · 2nd Year
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What is "oil-canning," and how do I cross-brake duct to prevent it?
Apprentice question · 2nd Year
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What is the proper spacing for tek screws on a 24-inch round slip joint?
Apprentice question · 2nd Year
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What's the best way to modify a square-to-round transition if the VAV is off-center?
Apprentice question · 2nd Year
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Why can caulking louver weep holes cause water to back up inside?
Apprentice question · 2nd Year
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Why do parallel 45-degree offsets need different travel lengths?
Apprentice question · 3rd Year
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Wrong notch/tab layout on fitting
Field problem · 2nd Year
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Wrong tool for cut and damaging duct
Field problem · 2nd Year
Coordinate
Failing to verify that shop drawings match the approved submittal before fabricating a full run
Common mistake · 3rd Year
Coordinate
Not maintaining the shop's plasma table cutting head consumables on a defined schedule
Common mistake · 3rd Year
Coordinate
Not vacuuming metal chips before handoff
Field problem · 3rd Year
Coordinate
Radius Elbows And R/W Ratio
Foreman script · 2nd Year
Coordinate
Rectangular Reducers And Increasers
Foreman script · 2nd Year
Coordinate
Round Branch Clocking: Mark the Tap Direction Before Cutting the Main
Field problem · 3rd Year
Coordinate
Round-To-Rectangular Transitions
Foreman script · 2nd Year
Coordinate
Shop Fittings Vs Field Fittings
Foreman script · 1st Year
Coordinate
Someone wants me to cut into a live or pressurized duct system
Field problem · 3rd Year
Coordinate
Spin-In Fittings To Flex
Foreman script · 1st Year
Coordinate
Tees, Wyes, And Crosses
Foreman script · 2nd Year
Standard
A spiral pipe cut is crooked and the run goes banana
Field problem · 1st Year
Standard
Deburr cut metal
Foreman script · 1st Year
Standard
How do I avoid the full-jaw apex tear (over-closing the snips)?
Apprentice question · 1st Year
Standard
How do I avoid the loose bull-nose pivot drift?
Apprentice question · 1st Year
Standard
How do I avoid the loose-shaft hole-saw core wobble?
Apprentice question · 1st Year
Standard
How do I avoid the red-snip right-hand bind (using the wrong color)?
Apprentice question · 1st Year
Standard
How do I avoid the scorched air-nibbler cutting die tracker?
Apprentice question · 1st Year
Standard
How do I avoid the smoking turbo-shear burnout (speed vs torque)?
Apprentice question · 1st Year
Standard
How do I fix a round pipe that's been crushed during shipping so it fits together?
Apprentice question · 2nd Year
Standard
Radius Elbows And R/W Ratio
Field problem · 1st Year
Standard
Rectangular Reducers And Increasers
Field problem · 1st Year
Standard
Round-To-Rectangular Transitions
Field problem · 1st Year
Standard
Shop Fittings Vs Field Fittings
Field problem · 1st Year
Standard
Spin-In Fittings To Flex
Field problem · 1st Year
Standard
Tees, Wyes, And Crosses
Field problem · 1st Year
Standard
What's the formula for finding the throat radius of a standard 90-degree elbow?
Apprentice question · 2nd Year
Standard
Why did my 45-degree offset travel piece fall short?
Apprentice question · 2nd Year
Reference
Field-measure transition
Reference · 1st Year
Reference
Offset measurement basics
Reference · 1st Year
Reference
Red-zone measurement before cutting
Reference · 1st Year
Reference
Why Duct Sizes Change Along a Run
Reference · 1st Year