YouTube sheetmetal tricks.

The use of the screen tool was great, I'll be using that one in the future. I had not seen those S lock parts until now. I have always wanted to play with Pittsburgh joints but in aircraft they are seldom used. I built a crazy Y-pipe for our cooktop exhaust which went through a concrete block wall (into the garage) but around a concrete filled and re-barred vertical cell. The quote I got was for Pittsburgh joints in galvanized steel all around. I really wanted to see if they could actually pull it off but it would have cost me $3500 (!!) for that bit of fun. I built it myself in stainless and TIG welded the joints. Did the design in Solidworks and had the complex parts cut on a CNC nibbler;

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My wife calls it "gorilla butt". :) The exhaust goes through a fan in the attic and then vertically out through the roof......Bill

Well done! Making those offset curves must have been loads of fun, both in the design and the execution. It is difficult to imagine doing this design without a tool like SolidWorks. Did you form the curves as you went? How did you finish the "butt crack"?
 
the YouTube AI made this one pop up and this guy did great job IMHO. As with anything it seems once you get the basics it’s all about tricks and shortcuts. HVAC ducting has always fascinated me and anytime someone wants to show you how to do something with just hand tools I’m all in.

He shows how to make a plenum box and introduces several super handy tools. The first one he calls bulldog snips which are short snips perfect for doing inside corners. The next one is using a screen spline tool that’s a double ended roller for installing screen splines when installing screen in frames. He uses it to do the stiffening X’s, very slick. I happened to have one and just replaced the screen on our back sliding glass door. And the last one was S lock which I’d never heard of which is used for joining sheetmetal. A comment was to make Pittsburgh locks which is similar but needs a brake to make where you can supposedly buy S lock somewhere. Another handy tool for 1” bends he had was a 15” slotted plate. I have a short 6” version and have used it a couple of times.

Hope someone finds this useful.
NOTE:
DO NOT USE SINGLE FOLD FLANGE AT BOTTOM OF THE PLENUM!

I've seen more than a few homeowners and installers who tried to squeeze past a furnace in a tight location who opened up long gashes on the raw edge of a single fold flange. You must use a 1/2 double safety flange so that the outside edge is the rounded outside of the fold.

I installed ductwork for many years, including working my way thru university doing so. Upon graduation I started an hvac company. In Canada we do ducts far differently than you'll do in the US, so it is always funny to me when I see your metal duct practices and hear your terminology.

Typically we'd order metal fittings to be premade based on an hvac design, but on occasion I'd make my own either for an emergency, or when I was trying to fit a coil in a plenum and there was already cuts made in the plenum that compromised the integrity of the ducts.

We had enough tools to carry so like Alton Brown says "single use tools are fit for the garbage only" and that screen tool wont hold up over time. You put the brake or crease in the duct with a large slotted screw driver. It works a charm, never breaks, has a thousand usages, and is so handy prying under a plenum lip when you want to slide a replacement furnace under a hanging plenum during a re & re.

Up here we refer to that as "S" cleat, and it's partner as "drive" cleat. It is also too expensive and important to use in the manner shown.

I always carried a stock of rectangular sheet metal that I'd run one of the short sides thru the Pittsburgh lock former so I could make up clean looking airtight plenums on a jobsite in seconds that cost far less. When you buy plain sheet metal to make ductwork yourself a legit supplier will put a pittsburg lock on one end for you for free. Two pieces of duct with a single fold in the middle and a short fold on the end make up a plenum with only two seams that are completely folded over for air tight seam as below.
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The end cap simply has a double fold that gets pinched tight with folding pliers to make air tight seal, then secured with a few sheet metal screws. Cheapest, more efficient and air tight method possible.

That all said, if I were to build a new home that had ductwork now, I'd use fiberglass ductboard because such systems are far quieter, and more inherently air tight when installed properly so better air distribution and easier balancing with such systems. Ductboard is hard to acquire in southern Ontario and the closest training for installers was in Grand Rapids Michigan.

That said, I'd only have an HRV that was ducted, because I'd go with radiant heating and cooling with heat pumps
 
Hi Tony, I went to homedepot.com and searched on "hvac ducting" and eventually found it on the eighth page:
https://www.homedepot.com/p/Master-Flow-60-in-S-Cleat-CS60/100170140
I bow to your Google-Fu Brian. Unfortunately is says unavailable here and unavailable for shipping, drat, foiled again!
RJ, I saw that one too:
https://www.homedepot.com/p/Klein-Tools-18-in-Folding-Tool-86532/304788047
....and it says 24 regular and 28 gauge stainless, and comes in 12, 18 and 24-inch lengths.
I was looking through the tools in HomeDump and saw, and bought the 6" version. It has come in handy a couple of times and might come in handy for an upcoming sheetmetal project using 24ga to make a special rain gutter.
 
Well done! Making those offset curves must have been loads of fun, both in the design and the execution. It is difficult to imagine doing this design without a tool like SolidWorks. Did you form the curves as you went? How did you finish the "butt crack"?
in the old days we'd use smacna rules and have hand drawn a bunch of templates for cutting out the parts of standard fittings. Then if a custom fitting came in the most experience layout person in the shop would have to figure out the curves.

now it is all done by cnc controlled plasma tables. The software has a million types of fittings that you drill down in menus to select the type fitting required, enter a few dimensions and hit "cut"
 
that screen tool wont hold up over time.
I get you are a pro and appreciate your input, but the whole premise was "hand tools only" and geared towards DIY. If you've ever done a screen I would venture to guess it would last far longer doing those creases than doing screens and mine is all plastic and probably 25yrs old. The spline the local hardware store had was hard and tough and it was a job doing that screen door. As to getting somebody to do a Pittsburgh cleat for me, that remains to be seen. I've not found anybody yet who'll even supply the S cleat.
 
I get you are a pro and appreciate your input, but the whole premise was "hand tools only" and geared towards DIY. If you've ever done a screen I would venture to guess it would last far longer doing those creases than doing screens and mine is all plastic and probably 25yrs old. The spline the local hardware store had was hard and tough and it was a job doing that screen door. As to getting somebody to do a Pittsburgh cleat for me, that remains to be seen. I've not found anybody yet who'll even supply the S cleat.

It is just as easy to find a real ductwork supplier to buy your sheet metal as it is home depot. I've actually never seen large rolled sheets at the home depot. Home depot doesn't have a pittsburg lock former just hangin round either so you'll never get free folding on your edges.

aside from buying appropriate metal to begin with my method is faster, cheaper and uses fewer hand tools. That's the point.
my method wont seriously injure someone either. The difference between a pro and an amateur...

You shouldn't take criticism of the guy in the video as personal criticism towards yourself, it colours your commentary. I'm sorry that I sought to help simplify jobs and protect people and clearly offended you
 
Well done! Making those offset curves must have been loads of fun, both in the design and the execution. It is difficult to imagine doing this design without a tool like SolidWorks. Did you form the curves as you went? How did you finish the "butt crack"?

Thanks! I was fairly new to SWx 22 years ago and this was a learning exercise in 3D CAD that got built.

Yes, the curves were formed as I tack welded the parts. Once the parts were cut out they were kinda' self-jigging, you just had to start tacking with the corners aligned. The curves literally just fell together. I had no idea that the CAD model would produce parts that worked so well in the real world. The two butt crack sheets were welded together first such that the weld was on the inside of the assembly. I think I measured the angle local to that joint in CAD so I could get it right and not have to fight with it later when all the parts were being tacked to each other.
 
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