Features
- Embedded magnets for precise punch setup
- Crosshairs on die surface to aid alignment
- Cuts up to 10 gauge mild steel and 12 gauge stainless steel
- Laser-etched markings to distinguish sizes
Specifications
| Size | 3 in |
| Material Capacity | Up to 10 gauge mild steel; up to 12 gauge stainless steel |
| Alignment Aid | Embedded magnets and crosshair alignment marks |
| Markings | Laser-etched size markings |
| Compatibility | Requires a hydraulic knockout tool (sold separately) |
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3" knockout die for producing conduit holes. When used with a compatible hydraulic knockout tool (sold separately), it can punch up to 10 gauge mild steel and 12 gauge stainless steel. The die includes embedded magnets to assist alignment on mild steel and laser-etched markings for size identification.
Project Ideas
Business
Mobile Panel Knockout Service
Offer on-site 3" conduit hole punching for electricians, solar installers, and HVAC techs. Bring a compatible hydraulic driver and use the die’s magnets/crosshairs to quickly add clean openings to enclosures, gutters, and panels up to 10 ga mild steel or 12 ga stainless.
Pre-Punched Enclosure Plates
Produce and sell standardized enclosure lids and blank plates with precisely located 3" knockouts. List SKUs for common patterns (centered, offset, multi-hole arrays) and custom layouts using the alignment marks for repeatable accuracy.
BBQ/Smoker Vent Kits
Fabricate retrofit vent kits for smokers and grills: one 3" punched hole plus a sliding damper plate or cap. Offer mild steel and stainless options; include a template, hardware, and finishing washers for a clean DIY install.
3" Steel Slug Supply
Collect and deburr the 3" round slugs from punch jobs and sell them as stamping blanks, coasters, branding tags, or craft pieces. Offer surface finishes (raw, sanded, blackened) and custom laser etching for logos.
Van/Food Truck Upfitting
Provide precise 3" pass-throughs for wiring, plumbing, and venting in vans and food trucks. The die’s magnets help hold on mild steel body panels while you align holes to templates for a speedy, clean install.
Creative
Industrial Porthole Frames
Punch 3" openings in sheet steel to create porthole-style picture frames or mirror surrounds. Use the embedded magnets and crosshair markings to evenly grid multiple holes across a panel, then back the openings with glass/acrylic and mount photos or mirrors for a clean, factory aesthetic.
Speaker Port Panels
Make bass-reflex ports or cable pass-throughs on DIY speaker enclosures. The precise 3" cut lets you seat standard port tubes or grommets; alignment marks help mirror left/right cabinet layouts for a professional finish.
Fire Pit Airflow Rings
Punch perfectly spaced 3" vents around mild steel fire pit shells to improve airflow and smoke control. Use the crosshairs to mark consistent spacing and the magnets to keep the die steady on curved or vertical surfaces.
Planter Drainage and Aeration
Convert steel buckets or stock tanks into planters by punching 3" drainage/aeration holes. Add mesh inside the hole to keep soil in place. The die’s magnets help you hold position on mild steel surfaces while you align clean, repeatable holes.
Circle Art With Slugs
Use both the 3" holes and the punched slugs to create geometric wall art. Arrange slugs as raised elements on a backing and layer perforated panels in front for a kinetic, light-and-shadow effect.