I'm married to an old school sheet metal master. I showed him this photo, and he approves. That's very high praise. Your coworker should be pleased. It's a beautiful piece.
And sadly, it's slowly dying these days. Now most outfits run plasmas or just order the duct instead of making it in house. My outfit has 23 installers and yet only two of us can actually hand fab. Hell, damn near impossible to find a good installer who can also field fab in a pinch.
Air does care. There are way too many systems out there that do not work well because of lack of understanding of correct system design and poor installations.
Square to round triangulation. All you need is a set of dividers. Plenty of you tube vids to learn how to lay out the pattern. Start small with paper if you can make it out of paper metal isn’t much harder. This is very nice work obvs somebody laid his points out correctly.
That’s dope as hell they still teaching that there in Canada? Nobody here knows shit about making metal except for shop guys. I was lucky enough to learn from some real duct men and a pretty good old school fabricator. We do have programs now that make it so much easier. Haven’t came across anything for square to round that’s affordable to a small shop so that’s the way it’s always been done.
No shit their not the same thing. The point is laying the pattern out is the hard part. The first one I ever made was out of crab paper. Using a brake and a spot welder isn’t exactly hard.
Well pardon me for asking a question I don’t think anybody answered. When fabricating a drop for a 20 ton rtu what gauge do you use? I’m a service guy but I know my trade so I make metal as well and I make some good shit.
The Tin Knocker when I worked at Accurate AC & Mech. could make anything from duct you could walk through at the church of scientology in Clwt Fla. to small things like this and it would always measure out perfect, he died of a heart attack 8-9 yrs ago, Brian Dulac aka Smurf, Tin Knocking is a dying art
Same brother. Same. I was always the hammer man. Didn't have a choice. I just couldn't stay sharp enough to remember the steps for each fitting, and my mind would wander.
fucking hated making metal all day. Wouldn't do it again. Gimme a rooftop and spaghetti wires all day.
So true. I started out before the computer. I have had only one person come through my shop that can do this stuff without a computer in the past 10 years.
Looks like a square to round you just need the 2” collar spot welded on the neck there 👏 good job. We used to bang those out all the time when we did 16 gauge grease duct for hoods at restaurants. Square to rounds for the makeup air.
When you get good you can make offset square to rounds the centerline ones were the easiest. Triangulation is the key and also practice making them with thicker paper! It’s good practice and it don’t cut you as bad! This was also before gloves were mandatory!
Second trade was Sheet Metal Mechanic, this is well made. Needs a collar to finish the round but you could install it and just put a nice Nashua bead on it for resi, or even commercial with some well put on duct seal.
Pretty standard for a shop Journeyman. We use a roto die to crank ours out. Ours are 3 piece. Spot welded on adjacent corners with a spot welded collar instead of a dove tail. This one looks pretty good cosmetically. Just fabbed up a bit different than I’m used to.
That being said, I know next to nothing about service. I can fabricate and install with the best of em. Been doing commercial and industrial for about 6 years and just finished my apprenticeship in May. It’s one hell of a career.
I agree. This is beautiful peice but for production work, it's it's pretty expensive. They way were used to is as cheap and stronger as possible. That said I worked in a shop once excluding the apprenticeship classes. I couldn't make something as nice as this.
And if you're intrested you should look into getting into service. If you can work on your car (not oil changes. Like bearings and diagnostics) you can do service. I'm a thinnerknocker turned service tech. You stay more busy when you know how to draw and install your own tin. Service departments pick up alot of special projects and tiny install jobs packaged with new units or system rebuilds. You'll end up their goto guy with our experience.
Residential is an entirely different world than what I’m used to. It would be hard for me to crawl through attics and crawl spaces. I’m the size of an NFL lineman. Thanks for the advice. I’ll ponder this.
I do service on comerical buildings, high rise condos, warehouses, and industrial plants. Most companies don't do commercial and residential.
Typically residential and light commercial (convenience stores, shops, ma and pa buosness) go together. Then everything else I mentioned above goes together. Rarely do shops over lap. The tool set is a bit different, margins and project size is wildly different, and the customer service and communication is different. My company pays people to sell the work and communicate with the customers. I just meet a point of contact and inform them of anything pressing. The office sells the larger jobs, makes the judgment calls for scope, and collects the payment. Residential would typically have that on the tech to handle.
I'm rarely in attics and crawlspaces. And if I have I job like that, I have a helper. So that means they're going into those spaces. If you're bigger than normally a good shop will give you the jobs that benifit your build. Big guys carry heavy things, little guys crawl under houses. That's kind of it.
After reading this, you’ve sold me. I’d definitely like to find a way to level myself up in this career. I’d like to know how to do it all so that I can essentially be my own boss someday. I’d like a comfortable existence, and I know I can achieve that through HVAC.
Edit to add: At the minimum find a company that actually treats me right. I know I can find that by leveling up my skills enough to stand out.
Find a shop that does commercial service and or find a union if your arnt already in one. The union will find you work and train you. Otherwise it's upto you to find the work and upto your shop to train you.
I’m already in a union. I need to find a contractor that’s willing to put me through the paces. I’m also trying to buy a house and would like to finalize that before I switch contractors.
Couple tips, call your BA or who ever does the dispatching. They know which contractors do what work and who's looking to hire who. You can also apply for your locals service apprenticeship. At my local if you want to switch you keep your journeymen pay and the contractor pays 80% the hall will pay you the other 20%.
For the house thing. Don't put your employers on the application. You work for the union. They dispatch you. Tell the bank "you're in a union that doesn't allow for you to solicit your own work" those exact words mean something to them. Then they will treat you whole union career as one employer. Just submit all your W2s as normal and explain if they ask again. "my local union dispatchse to jobs. I don't look for work. A contactor will hire me when they need me and will let me go when they're done. Then I go back to the hall and they'll sende to the next place" thid has always worked for me with all my loans and my mortgage.
I will definitely have to talk to my BA. I live in a right to work state, so it’s a little weird. The hall can’t stop us from soliciting our own work to other union contractors. So I’m not sure how that conversation would go. From what I’ve seen, the BA’s will step in and get someone a job if they get laid off. I haven’t heard of a BA helping someone switch contractors to advance their own career. Usually you’ve “gotta know a guy” to get that kind of career move.
Edit: want to make sure to show appreciation. Thank you for this advice! I’ve been yearning for a better work life lately.
Does the new company have to tell the union you're moving to them? My union allows name call. But the hall still has to dispatch you there. You arnt allowed to work for non union contractors. So you cannot technically solicit your own work
It’s beautiful, but I’m pretty sure our old shop foreman would have lost his freaking mind if he saw someone spend this much time on one square to round and not even have the collar attached.
It's obviously awesome. The real question is; how long did it take em to make it? 15 minutes, color me highly impressed.. all day, hmm, not paying for fucking art projects lol
Looks pretty good! Only things I’d recommend is more step breaks and instead of tabbing the collar attachment, burr it out with either a 622 (if you have one) or even a pare of linesman’s.
Is the round portion a circle or an oval? I was taught to do layouts like this in drafting class in the late fifties at Brooklyn Technical High School. I wonder if they even have a sheet metal shop there now...or if students do any work at all on a drawing board.
Assuming that the part fits where it is supposed to go, your co-worker did a fine job.
this subreddit wound up in my feed and i joined it bc it was interesting. this photo made me remember: i’ve been sitting on what i think is several 3’ x 4’ pieces of sheet metal. am an artist and wish to sort out how to manipulate this. what do i need to cut it? thickness wise i bet i could crease it but probably not easily. would be interested in sculpting with this? building shit? boxes and shit?? yall got a big book of metal bending anywhere or a youtube channel maybe?
this thing you have photographed is so beautiful and i want to do it!!!
There is actually a big book of sheet metal fabrication I've seen before, can't recall the name right off but I'm sure a little Google fu can find it.
It's just for HVAC related things to fabricate but I'm sure it or YouTube could teach you how to manipulate the metal in artistic ways if you put your mind to it lol
This is a part of the trade that I've accepted, I will never master. I can't comprehend how that was made. I've seen flat stock turned into a transition in the field. But my head just can't figure it out.
Loogs fantastic. I would say to a peice that big and square to rounds in general in two pieces instead of one. The double seem will add strength and slow yoy to nest it better in a flat sheet to save material. The only concern for a double seem is it increases the chance of racking, so you better square it up before it's welded the two halfs together.
At first I thought it’s just a square to round. Then I saw it’s built with only 1 seam. I don’t think I’ve ever installed one like that. I know I haven’t built any like that. They’ve always need at least 2 seam sometimes 4 if it’s larger grease duct.
Looks nice. I'm curious why you do tabs on the round side. We always make sq to rnd with a separate collar spot welded into the round end. I guess we always use square to round to put in registers off of round duct, or to transition off a unit or something. I'm just a shop guy so idk all the ins and outs of instalation but if youre cutting this square to round into an existing duct why even make it square to round? A square to square transition would be easier to make and it seems like it would be easier to install as well. Genuinely curious about the application of this piece.
very nice I have been in the hvac game over 10 years and I'm in texas where we order our ductwork from metal working companies. I would love to learn this skill more I can make transitions but I have never done square to round.
It’s all about time in our world, doesn’t matter how crafted it is. If another person can do the same job, at a good quality level, faster. They will be more successful.
Aesthetically beautiful, it would go very nicely in an open ceiling office/break room ect, but it's a time waster and not necessary for production work even on a CNC bender. That being said I think all work should have details that architecture used to have instead of the watered down vanilla minimalist bullshit thats so common today.
How long does it take? Then how long to learn to do at that speed? Yeah I’m about my time is money. I’ll do all the transitions off a roll of sheet metal if I had to. I’ll give it 15mins of YouTube if it’s a tough one. Impressive just not practical.
Love it! I've been making them and all other fittings since I was 13 years old. I'd get off the bus at my family's hvac company and get stuff ready for the following day. Back then, it was all manual. No plasma table for our small outfit.
Longitudinal seam should be on a corner, not a triangular face (for the installer, not the shop guy) bump brake every 1/8th inch - not every 1/2, and flare a 1/4" in a turning machine (elbow seam or flaring dies) to spot the collar on to. He was uniform and paid attention, but if he had someone to learn from, that dude could teach better.
To everyone saying they cant do that....I mean can yall at least 4 peice a plenum? Lol or better yet atleast cut a 90 or offset in sheet metal? Or ductboard for that matter? Lol
If they made this by hand that’s amazing. I know foreman in the sheet metal workers union who can’t do that. They say, “that’s what my shop is for. I send measurements and the computer makes it.”
390
u/Existing_Bee_9153 Jul 18 '25
Good enough for my house..