400A 29 PC Set

DRILLCO 400A 29-Piece Heavy-Duty HSS Drill Bit Set — Precision Drilling in Medium and High Strength Materials

The DRILLCO 400HD29 is a 29-piece jobber-length drill bit set engineered for heavy-duty drilling applications in medium and high strength materials, including stainless steel and tougher ferrous materials. Manufactured in the United States from premium grade high speed steel (HSS), each bit features a 135° split-point geometry and a black oxide surface treatment. This set is sized from 1/16" to 1/2" by 64ths, covering the full range of common jobber-length drilling tasks encountered by contractors and trades professionals.

Technical Specifications

Available Sizes

Unlike general-purpose HSS sets with a conventional 118° point, the 400HD29 uses a 135° split-point on every bit, reducing thrust requirements and minimizing walking — characteristics that matter when drilling stainless steel and other tougher ferrous materials where bit control and reduced setup time are critical. The black oxide surface treatment further extends tool life compared to a bright-finish bit by reducing friction and heat damage during use.

Key Features & Benefits

Premium Grade HSS Construction

Each bit in the set is manufactured from premium grade high speed steel, providing the hardness and wear resistance needed for demanding drilling in medium and high strength materials. HSS construction ensures the bits maintain their cutting edge through repeated use, reducing replacement frequency on the job.

135° Self-Centering Split-Point

The 135° split-point geometry is self-centering, which minimizes walking when starting a hole — particularly valuable on curved surfaces or when hand-drilling harder materials. It also reduces the thrust required to begin cutting, decreasing operator fatigue and the risk of bit breakage on tough workpieces.

Black Oxide Surface Treatment

The black oxide finish reduces friction and heat damage during drilling operations, directly contributing to longer tool life. This treatment is suited for performance on low to medium tensile strength materials and provides improved durability over uncoated bright-finish bits.

Jobber Length for Versatile Reach

Jobber length is the most common drill bit length because it provides extra reach while remaining usable across the widest range of applications. This makes the 400HD29 set a practical all-around solution for contractors who need one set to handle most drilling tasks on a job site.

Full 29-Piece Size Range

The set covers 1/16" to 1/2" by 64ths, giving contractors access to every increment needed for precise hole sizing without switching to a different set. Having the complete range in a single kit reduces downtime spent sourcing individual bits.

Made in the United States

Domestic manufacture supports consistent quality control and supply chain reliability. For contractors and procurement teams with domestic sourcing requirements, the U.S. origin of the 400HD29 is a verifiable specification.

Common Applications

Drilling in Stainless Steel

The 135° split-point and premium HSS material make this set specifically suited for drilling stainless steel, where conventional bits often walk or overheat. The reduced thrust requirement of the split-point helps maintain control in this demanding material.

Heavy-Duty Drilling in Tougher Ferrous Materials

Designed for more demanding applications, the 400HD29 handles medium and high strength ferrous materials where general-purpose drill sets fall short. The heavy-duty construction supports repeated use in production or field drilling environments.

General Jobber-Length Drilling Tasks

Jobber length makes these bits suitable for the majority of through-hole and blind-hole drilling tasks encountered in construction and fabrication. The full size range from 1/16" to 1/2" covers standard fastener clearance holes, pilot holes, and general metalworking needs.

Product Documents

• Safety Data Sheet (SDS)
• Drillco Product Linecard

Safety Data Summary

Hazard Information

• During normal operation and usage, high speed steel products do not present inhalation, ingestion, or other chemical hazards.
• Operations such as grinding, cutting, machining, burning, and welding may release dusts, fumes, or vapors that present health hazards if exposure limits are exceeded.
• Excessive inhalation of metallic fumes and dusts may cause irritation of eyes, nose, and throat; symptoms may include metallic taste, dryness and irritation of the throat, chills, and fever persisting 12 to 48 hours.
• Chromium (present 0–5% by weight) is listed as a carcinogen by NTP and OSHA; various forms of dermatitis, inflammation and/or ulceration of the upper respiratory tract, and possibly cancer of nasal passages and lungs are associated with chromium exposure.
• Tungsten (5–10% by weight): some evidence of pulmonary involvement such as cough.
• Vanadium (0–5% by weight): eye and respiratory tract irritant.
• Molybdenum (5–10% by weight): eye and mucous membrane irritant; individuals with kidney, chronic respiratory, or liver disease may be at increased risk.
• Dust from grinding may cause irritation of the nose and throat and has the potential to cause transient or permanent respiratory disease including occupational asthma and interstitial fibrosis.
• Skin contact with dust can cause irritation or allergic skin rash due to cobalt sensitization.
• Fine metal particles produced when ground or sawed can burn; high concentrations in air may present an explosion hazard.
• NFPA Hazard Rating: Health 1; Flammability 0; Reactivity 0.

Personal Protective Equipment

• Wear safety glasses or goggles with side shields; do not wear contact lenses when handling these materials.
• Cloth or leather gloves are recommended when contact with dust or mist is likely.
• Use an appropriate NIOSH-approved respirator if airborne dust concentration exceeds the applicable PEL or TLV.
• Hearing protection may be required.
• Always use machine guards and wear protective clothing to prevent injury in the event of tool breakage.
• Employer should provide an eye wash station within the immediate work area for emergency use.

Safe Handling

• Use only with local exhaust ventilation adequate to limit personal exposure to airborne dust below PEL or TLV levels.
• All grinding, cutting, and machining operations should be performed in well-ventilated areas.
• Wash hands thoroughly after handling and before eating or smoking; wash exposed skin at the end of the work shift.
• Do not shake clothing, rags, or other items to remove dust — remove dust by washing or vacuuming with appropriate filters.
• Soiled clothing should be laundered separately.
• Store in a dry place; store in a manner that prevents accidental environmental contamination from traces of industrial lubricants or wetting oils.
• Clean up spills using methods that avoid dust generation such as vacuum (with appropriate filters), wet dust mop, or wet clean-up.
• Incompatible materials: strong acids, strong oxidizers.
• For powder fires, smother with dry sand, dry dolomite, ABC type fire extinguisher, or flood with water.
• Dispose of waste material in compliance with federal, state/provincial, and local environmental regulations; send to an appropriate reclamation facility if available.

Frequently Asked Questions

Q: What materials is the 400HD29 set designed to drill?
A: The set is designed for drilling holes in medium and high strength materials, including stainless steel and tougher ferrous materials. It is built for heavy-duty drilling applications where general-purpose bits may be insufficient.

Q: Why does this set use a 135° split-point instead of a standard 118° point?
A: The 135° split-point is self-centering, which reduces walking when starting a hole and lowers the thrust required to begin cutting. This makes it better suited for harder materials and hand-drilling on curved surfaces compared to a conventional 118° point.

Q: What sizes are included in the set?
A: The 400HD29 includes 29 pieces covering 1/16" to 1/2" by 64ths, providing every 64th-inch increment across that range.

Q: What does the black oxide surface treatment do?
A: Black oxide reduces friction and heat damage during drilling, which increases tool life. According to Drillco's linecard, black oxide surface treatment is suited for performance on low to medium tensile strength materials.

Q: Are speed, feed, and lubrication important when using these bits?
A: Yes — Drillco specifically notes that speed, feed, and lube are all critical to cutting tool performance. Using appropriate cutting fluid and correct feed/speed settings will maximize bit life and hole quality.

Q: Where are these drill bits manufactured?
A: The 400HD29 set is manufactured in the United States.