Bob and the Curved Duct Fitting

I hung out with Bob today, going down to Frankfort with him where he had some work to finish up. I was mostly along for the second half of our day, there to assist in packing up tools and putting away a big scaffold outside.

The job he had involved getting a round piece of duct to fit into a curved duct. He mentioned how few guys nowadays would know how to do something like this, and I decided a few photos were in order.

Here’s the curved portion that he needed to mark and cut into.

Cutting out the space he needs.

Starting with a circle.

Marking where he needs to cut on the new piece of duct that will be fitting in.

Lines ready to go. Right around here is where the math and sizing process escapes me.

The piece, cut down to size.

Beading the piece by hand. Normally, there’s an adjustable back that the duct rests against. But since this was a fairly irregular shape, it needed to get turned by hand.

Adding in tabs, old school. Bob mentioned that the tool he was using belonged to his grandfather.

This moment caught me by surprise. I knew his father was in the trades, but didn’t remember that his grandfather was as well. I thought about the passage of time, and how Bob was part of the third generation in his family to continue this line of work.

I also remembered all the various buildings and skyscrapers Bob’s worked in, over his career – and imagined all the various installations, both big and small, that he’d done. And how long those buildings had been around (and will be around).

The finished tabs.

After several tests and fits, the circle assumes its final, oval shape.

The new piece, fitting snugly in place.

Two elbows linked together.

Finishing up with some tek screws. Given the tight quarters, Bob was using two neat extensions: one flexible length, and one that allowed him to go in at a 90 degree angle.

Hard to see, but this is the final duct all glued up.

Related:
New Ductwork Begins