Features
- Manufactured to consistent specifications
- Split point design to reduce walking and start on contact (no center punch typically required)
- Black oxide finish for improved surface durability
Specifications
| Model Number | BL4003 |
| Pack Quantity | 12 (bulk) |
| Diameter (Gauge) | #3 |
| Diameter (Decimal Inch) | 0.212998 |
| Flute Length (L1) | 2.0 in |
| Working Length (L1) | 2.0 in |
| Total/Overall Length (L2) | 3.75 in |
| Shank Diameter | 0.212998 in |
| Finish | Black oxide |
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Set of wire-gauge twist drill bits intended for general-purpose metal drilling. Each bit has a split point to reduce walking and start on contact (so a center punch is typically not required). The black oxide finish provides increased surface durability and some corrosion resistance.
Model Number: BL4003
Project Ideas
Business
On-Demand Drill & Tap Service (1/4-28 Specialty)
Offer a mobile or mail-in service drilling #3 holes and tapping 1/4-28 UNF in brackets, plates, and automotive/motorsport parts where fine threads are preferred. Market to robotics teams, race shops, and makers; charge per hole plus setup, with upsells for deburring, chamfering, and coating.
Universal Bracket Kits
Produce small-batch steel/aluminum brackets pre-drilled with a grid of 0.213 in clearance holes for #10 hardware and select 1/4-28 tapped holes. Sell as DIY mounting kits for vans, CNC enclosures, 3D printers, and shop storage. Include fasteners and templates to justify higher margins.
Perforated Lighting Products
Design and sell perforated lampshades, sconces, and acoustic panels with decorative drill patterns. Use the split-point bits for fast, accurate production. Offer custom patterns (logos, monograms) and batch discounts for interior designers and cafes.
Workshops + Starter Kits
Host paid classes teaching safe metal drilling, layout, and tapping. Provide a take-home kit: small sheet metal, a printed hole layout, deburring tool, sample fasteners, and a couple of #3 bits. Upsell students on expanded material packs and private project sessions.
Content + Affiliate Microbrand
Create short-form videos comparing drill techniques, pattern layout tricks, and using #3 as a tap drill for 1/4-28. Link to tool affiliates and sell downloadable templates (hole grids, lantern patterns), generating revenue through sponsorships and digital products.
Creative
Perforated Metal Lantern
Drill decorative dot patterns into thin steel or aluminum sheet to create a candle/LED lantern. The split point lets you start cleanly without a center punch, so complex stencils transfer easily. Deburr, fold into a cube or cylinder, and finish with heat-resistant paint for dramatic speckled light.
Dot-Matrix Wall Art Panel
Turn a photo into a halftone grid and drill 0.213 in holes in a sheet to form a portrait or geometric mural. Backlight it or mount over contrasting wall color. The consistent wire-gauge bits yield uniform hole size for crisp, repeatable patterns.
Custom Pegboard/Tool Organizer
Make a heavy-duty pegboard from steel with #3 holes laid out on a grid. Use #10 hardware through the 0.213 in clearance holes to attach shelves, hooks, or holders. Black oxide bits handle repeated drilling in mild steel without galling.
Fine-Thread Fixture Plate
Drill and tap select holes 1/4-28 (the #3 drill is the correct tap drill) into a small plate to build a modular clamping or camera-accessory fixture. Mix tapped holes with through holes for #10 fasteners to create a versatile, compact workholding board.
Wind Spinner With Stitched Patterns
Cut concentric rings from thin metal and stitch them with rows of evenly spaced 0.213 in holes. The perforations create visual texture and reduce weight; assemble with #10 bolts at pivots for smooth spinning garden art.