The drive is only partly seated

Finish seating the drive full length before tabs, sealing, insulation, or moving on. A half-installed drive leaves the hem unsecured.

Fix the seated side before finishing the drive. If the S-lock is not fully seated, the drive side may never pull the corner tight.

Rectangular Duct & Fittings 2nd Year YELLOW

Stop if

Ask when the drive will not seat without excessive force or the hem/connector is damaged.

Watch out

Do not seal or cover a joint that is only partly seated.

Check

Re-seat the S side
Check the corner gap
Verify the duct is not twisted or carrying weight

Steps

Check both ends of the drive.
Look for blockage, burrs, bent hems, or misalignment.
Seat the drive fully if the joint is square.
If it stops hard, back up and find the cause.
Recheck after lifting or moving.

Say this to your foreman

In Rectangular Duct Assembly: S-and-Drive, I'm looking at: The drive is only partly seated. What should I verify before I cut, drill, seal, cover, move, or install?