The two duct sections will not pull together

If two duct sections will not pull together, something is wrong. Find the cause before forcing it because forcing damages connectors and hides the real issue.

Rectangular Duct & Fittings 2nd Year YELLOW

Stop if

Ask when the duct needs excessive force, oil-cans, or appears wrong size/damaged.

Watch out

Do not hammer or force sections that are clearly fighting. You can distort the connector and make the recovery worse.

Check

Check whether both duct sections are square and not twisted.
Check whether the S-cleats, drives, flanges, or collars are fully and evenly started.
Check for debris, bent connector edges, or a drive/cleat that started crooked.
Measure both sections if the size looks off
a fabrication or field-cut mismatch will not pull together cleanly.
Try a safe re-position, flip, or rotation only if it makes mechanical sense and does not damage the connector.

Steps

Check whether both duct sections are square and not twisted.
Check whether the S-cleats, drives, flanges, or collars are fully and evenly started.
Check for debris, bent connector edges, or a drive/cleat that started crooked.
Measure both sections if the size looks off
a fabrication or field-cut mismatch will not pull together cleanly.
Try a safe re-position, flip, or rotation only if it makes mechanical sense and does not damage the connector.

Say this to your foreman

These two sections will not pull together. I checked squareness and connector alignment, and the issue looks like [out of square / bent connector / size mismatch / debris]. Do you want me to re-square it, replace a connector, or treat it as a fabrication issue?