Features
- Punches up to 10 gauge mild steel and 12 gauge stainless steel
- Laser etched markings to easily distinguish size
- Threads onto draw stud for punch and die setup
Specifications
| Size | 3-1/2 in. |
| Compatible With | 20V MAX hydraulic knockout tool (sold separately) |
| Maximum Material Capability | 10 gauge mild steel; 12 gauge stainless steel |
| Includes | 1 knockout punch |
| Markings | Laser etched size markings |
| Mounting | Threads onto draw stud (sold separately) |
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A 3-1/2 in. knockout punch for creating conduit holes. When used with a compatible hydraulic knockout tool and a draw stud (sold separately), it can punch through up to 10 gauge mild steel and 12 gauge stainless steel. The punch threads onto a draw stud for punch-and-die setup and has laser-etched size markings for identification.
Project Ideas
Business
On-Site Panel Knockout Service
Offer mobile punching of 3.5 in. conduit holes in control panels, junction boxes, and enclosures. Using the hydraulic knockout tool and draw stud, you can deliver fast, clean holes in up to 10 ga mild steel or 12 ga stainless for electricians and integrators on tight schedules.
Food Truck and Kitchen Retrofit
Specialize in punching 3.5 in. holes in stainless prep tables, carts, and panels for sink drains, waste chutes, cable pass-throughs, and grommeted ports. Market to food trucks, cafes, and commercial kitchens needing clean, code-friendly modifications in stainless.
HVAC/Ductwork Round Tap Installations
Provide precise 3.5 in. openings for round taps, sensors, and vents in sheet metal plenums and duct panels. Pair the punch with speed collars and gaskets to deliver airtight, repeatable installations that reduce labor compared to snips or hole saws.
Pre-Punched Enclosures and Plates
Batch-produce and sell mild steel or stainless blanks, covers, and adapter plates with 3.5 in. knockouts to electrical suppliers and panel shops. Leverage the punch for consistent sizing, clean edges, and reduced downstream deburring.
Tool Rental With Quick-Start Training
Rent out the hydraulic knockout tool paired with the 3.5 in. punch and draw stud, plus a deburring kit. Include a short safety and setup tutorial and a gauge chart. Ideal for contractors who need occasional large-diameter holes without buying the full setup.
Creative
Industrial Porthole Planter Panel
Punch a series of clean 3.5 in. circles into mild steel or stainless panels to create wall-mounted planter openings. Back each hole with a ring or cup planter and mount the panel as a living wall. The laser-etched size makes repeatable spacing easy and the punch leaves clean edges for a polished look.
Modern Lantern With Round Windows
Roll thin sheet metal into a cylinder and punch 3.5 in. windows around the body. Add acrylic diffusers or perforated screens behind each opening and place an LED light inside. The punch’s ability to handle 10 ga mild steel or 12 ga stainless gives a rigid, durable lantern with crisp circular cutouts.
Speaker Faceplate or Grill Art
Use the 3.5 in. punch to create precise openings for small speaker drivers or port holes in a boombox or media console face. The consistent diameter ensures symmetry and a professional fit for trim rings and grills, especially in stainless for a sleek modern aesthetic.
Cabinet Doors With Round Sight Windows
Convert plain metal cabinet doors into display pieces by punching 3.5 in. sight windows and inserting round acrylic lenses or tempered glass. The clean, burr-minimal cut from the punch makes finishing easy and yields an industrial-chic look.
Ventilated Storage or Compost Lid
Add multiple 3.5 in. aeration ports to metal bins or lids, backed with stainless mesh. Great for tool cabinets that need airflow or for garden composters. The punch creates uniform vents that accept standard grommets or trim bezels for a tidy finish.