First, the seam is the standard, not the brand
The Pittsburgh lock is a SMACNA-standardised longitudinal seam, and so are the snap lock, the drive cleat and the slip. Any properly set-up roll former produces the same interlocking pocket and flange, so duct from a new machine mates with duct you already build. What varies between makers is the pocket size (small Pittsburgh, about a 5/16 in pocket for roughly 26–20 ga; large Pittsburgh, a 3/8 to 1/2 in pocket for 18–16 ga), the gauge range, the number of stations and the speed. Our Lockformer alternatives guide explains the switching mechanics; Pittsburgh lock versus snap lock explains which seam to run.
Ownership: Lockformer and Engel are both Mestek Machinery brands built in Cedar Rapids, Iowa and sold through one dealer network; Vicon belongs to the Lindab group since 2024; Taokron is independent.
The comparison table
Figures are each maker’s published specifications; US gauges converted to millimetres in brackets by us. “Not stated” means the maker does not publish it.
| Machine | Gauge | Pocket | Stations | Speed | Drive | Other seams | Owner |
|---|
| Lockformer Pittsburgh Lock 16 | 16–20 ga (1.5–1.0 mm) | 1/2 in, uses about 1-3/8 in of material | 7, two forming positions | 40–45 ft/min (12–14 m/min) | 3 hp, 3-phase | Auxiliary rolls per catalogue | Mestek |
| Lockformer Pittsburgh Lock 20 | 20–26 ga (1.0–0.5 mm) | 5/16 in, uses about 1 in of material | 5, two forming positions | 25 ft/min (7.6 m/min) | 3/4 hp, single-phase | Flanging attachment option | Mestek |
| Engel 800 Series HB-800P-20 / -18 / -16 | 20–26 / 18–22 / 16–20 ga | Not stated | 8, two forming positions | 90 ft/min (27 m/min); 50 ft/min on the 16 ga model | Not stated | HB-800B snap lock (24–30, 20–26, 18–24 ga); slip-and-drive former | Mestek |
| Vicon V8 Pittsburgh | 18–24 ga standard (1.3–0.6 mm) | Not stated | 8, no opening roll | 90 ft/min (27 m/min); 60 ft/min single-phase option | 5 hp, oil-bath worm gear | V8 snap lock, V8 slip-and-drive; optional right-angle flange, 4-in-1, Acme lock | Lindab |
| Taokron SBLC-12 / SBLC-15 / SBLC-1.2 (R, DR, C variants) | Pittsburgh 0.4–1.2 mm (27–18 ga); snap lock 0.7–1.5 mm (22–16 ga) | Standard SMACNA pocket per model | Multi-station, see catalog | Quoted per gauge, FAT-verified | 1.5 / 2.2 / 3 kW, 3-phase | Snap lock, drive cleat, flange sets by variant | Taokron |
Brand and product names are the property of their respective owners, referenced here for honest comparison only. Ownership, positioning and published ranges are as verified in September 2026 from each maker’s own publications; confirm current specifications and support with each vendor before buying.
Reading the table honestly
- Speed is the least important column. A Pittsburgh former waits for the operator to feed the next blank; 25 versus 90 ft/min changes seconds per duct, not ducts per shift. Stations and pocket accuracy decide seam quality; gauge range decides whether the machine fits your work.
- Buy the pocket for your duct. A 26–20 ga shop wants the small pocket; an 18–16 ga shop wants the large pocket and the heavier frame. Lockformer publishes pocket sizes clearly; ask every other maker for theirs and get a formed sample to fit against your duct.
- Eight stations versus five or seven. More stations spread the forming load and are gentler on galvanising; Engel and Vicon publish eight. Lockformer’s five- and seven-station machines have made good seams for decades. A formed sample tells you more than the count.
- Auxiliary seams. Snap lock, drive cleat and flange rolls are brand-specific. Inventory every seam you form and confirm the new machine offers a station for each; Taokron’s R, DR and C variants exist for exactly this.
- Electrical. Lockformer’s Model 20 is single-phase; the rest are three-phase. Confirm your supply and, outside North America, 50 Hz.
- Dealer geography. Mestek and Vicon publish North American dealer networks; Engel lists the 800 Series as available for immediate delivery. Taokron ships worldwide with direct engineer support.
Where Taokron fits
This is our own entry, so read it as a vendor’s case. Taokron is an Australian supplier that has built HVAC duct machinery since 1995, with 5,000+ machines in 100+ countries, ISO 9001:2015 and CE certification and catalog-accurate published specs. The SBLC series covers Pittsburgh 0.4–1.2 mm and snap lock 0.7–1.5 mm across three frame sizes and three seam-set variants, on 1.5 to 3 kW three-phase drives, at export-competitive capital cost. We publish gauge ranges rather than a headline speed and quote throughput per gauge for the acceptance test. Most buyers take the SBLC with the TDF former, folders and shears or a full auto duct line, commissioned by one team. Best for: shops outside the North American dealer maps and anyone equipping a rectangular shop from one vendor. Weigh: Lockformer and Engel are the reference names with domestic dealers; ask us for a formed sample seam to fit against your duct before you decide.
Ask for an SBLC quotation with your gauge and seam list →
FAQ
Is a Pittsburgh machine the same as a Lockformer?
A Lockformer is a brand of Pittsburgh machine (Lockformer, a Mestek Machinery brand). The Pittsburgh lock itself is a SMACNA-standard seam that every maker’s roll former produces, so the words are used interchangeably in the trade but only one is a brand.
Which Pittsburgh machine is fastest?
On published speed, Engel 800 Series and Vicon V8 at 90 ft/min, then Lockformer Model 16 at 40–45 and Model 20 at 25 ft/min. In the shop, feeding blanks sets the pace, so speed rarely decides ducts per shift; seam quality and gauge range do.
What pocket size do I need?
Small Pittsburgh (about 5/16 in pocket) for roughly 26–20 ga duct; large Pittsburgh (3/8 to 1/2 in pocket) for 18–16 ga. Lockformer publishes 5/16 in on its Model 20 and 1/2 in on its Model 16; get a formed sample from any maker and fit it to your existing duct.
Are Lockformer and Engel competitors?
No. Both are Mestek Machinery brands built at the same Cedar Rapids site and sold through the same dealers.
Does Taokron make snap lock and drive cleat machines too?
Yes. The SBLC series covers Pittsburgh 0.4–1.2 mm and snap lock 0.7–1.5 mm, with R, DR and C variants carrying different auxiliary seam sets; a separate drive-cleat line and TDF former complete the rectangular seam and flange set.
Will duct from a different brand of Pittsburgh machine fit my existing duct?
Yes, if the pocket size and gauge match. The seam profile is a standard; roll sets are not, so budget new tooling and test-fit a sample before the old machine leaves.
