Best #19 Drill Bits for Metalworking, Repairs, and General Drilling
The best #19 drill bit depends on the material, access, and how many spares you need. For tough metals, Drill America’s cobalt bit is the stronger fit; its 6-inch aircraft extension is better for reaching recessed work. For general use, the Drill America HSS split-point set and MaxTool jobber-length set offer practical multipacks, while PATIKIL is suited to light-duty tasks and mixed materials. A #19 drill bit has a nominal cutting diameter of about 0.166 inches, or 4.216 mm.
| Product | Best For | Notable Feature |
|---|---|---|
| Drill America DWDCO19P12 | Harder metals | Cobalt steel, 12 bits |
| Drill America GLBCOX619 | Recessed or deep-access drilling | 6-inch extension |
| PATIKIL 10-Pack | Light-duty, mixed materials | HSS bits, 135-degree point |
| Drill America KFD19P12 | General-purpose drilling | HSS, split point, 12 bits |
| MaxTool No. 19 10-Pack | Jobber-length versatility | M2 HSS, 10 bits |
Drill America DWDCO19P12 Cobalt Drill Bit
This 12-piece set is best for people who regularly drill harder metals. Its cobalt steel construction is intended to improve performance in materials such as stainless steel and nickel alloys compared with standard high-speed steel. The round shank fits a wide variety of toolholding systems.
The gold oxide finish is a thin surface treatment; the listed product information says its performance is similar to uncoated tools. Choose this set when the work material is the priority and replacement bits on hand are useful. Avoid choosing it solely for the finish, which is not described as a performance upgrade over uncoated tools.
Drill America GLBCOX619 Aircraft Extension Bit
Best for drilling where a standard-length bit may not reach, this #19 cobalt bit has a 6-inch aircraft-extension format. Its listed applications include tough, high-tensile-strength materials such as stainless steel, Inconel, and titanium. A 135-degree split-point tip is designed to help prevent the bit from walking, and the round shank works with a wide variety of toolholding systems.
Choose this option when reach and harder materials matter more than having a multipack. Its extended length can be unnecessary for ordinary, open-access holes, so a standard jobber-length bit may be a more suitable choice for compact work.
PATIKIL #19 HSS Drill Bits, 10-Pack
This PATIKIL set is best for light-duty drilling across several material types. It includes ten 4341 high-speed steel bits with a 4.216 mm cutting diameter, 55 mm flute length, and 83 mm overall length. The 135-degree point and gold finish are listed among its features.
The stated applications include low-carbon and medium-carbon steel, aluminum alloy, brass, cast iron, stainless steel, acrylic, plastic, and wood. For thicker metal, the manufacturer specifies low RPM and flood coolant. That limitation makes this set a less suitable pick for demanding, heavy-duty metal drilling than the cobalt options.
Drill America KFD19P12 HSS Split-Point Set
Best for general-purpose drilling, this 12-piece set uses high-speed steel, which the product information describes as balancing hardness and toughness for wear resistance. The bits are listed for wood, metal, stainless steel, and other hard metals. Their 135-degree split-point tips are designed to reduce walking as the hole starts.
This is a practical alternative to cobalt when the job involves a broad range of materials rather than a specific emphasis on tougher alloys. Choose it if you want multiple general-purpose bits. For frequent work in difficult metals such as Inconel or titanium, the aircraft-extension cobalt option is more specifically described for those materials.
MaxTool No. 19 M2 HSS Jobber Drill Bits
This 10-piece set is best for buyers who want jobber-length bits for common shop materials. MaxTool identifies the bits as M2 high-speed steel with straight shanks and lists metal, plastic, and wood as suitable materials. The product description also states that drill dimensions and tolerances conform to ASME/ANSI B94.11M or USCTI standards.
Choose this set when a standard jobber-length format and multiple identical bits suit the task. The listed features do not specify a split-point tip or cobalt construction, so buyers who need those characteristics should compare the Drill America options instead.
Buying Guide: How to Choose a #19 Drill Bit
What size is a #19 drill bit?
A #19 wire-gauge drill bit is approximately 0.166 inches in diameter, equivalent to 4.216 mm. Confirm the required hole size before drilling, especially for precision or threaded work; a numbered bit size is not the same as a metric designation.
Should you choose cobalt or high-speed steel?
Cobalt is the more targeted choice for harder metals, including stainless steel and nickel alloys, based on the listed features of the Drill America cobalt models. HSS is a versatile option for general-purpose work across materials such as wood, plastic, and metal. Select according to the material and duty level rather than the finish alone.
Does length matter?
Use a standard jobber-length bit for ordinary access. Select an aircraft-extension bit when the work is recessed or requires added reach. The longer format is not automatically better for every hole, so match length to access and handling needs.
What does a split point do?
A 135-degree split point is designed to help prevent the bit from walking when starting a hole. This feature appears on the listed Drill America KFD and aircraft-extension models, as well as the PATIKIL option.
Frequently Asked Questions
What is the metric size of a #19 drill bit?
The listed #19 size is approximately 4.216 mm, or 0.166 inches.
Which #19 bit is best for stainless steel?
The cobalt Drill America models are the most specifically suited among these choices for harder metals, including stainless steel.
Can a #19 drill bit be used on wood and plastic?
Yes. The PATIKIL and MaxTool product descriptions list wood and plastic among their applicable materials, and Drill America lists wood for its HSS set.
Is the PATIKIL bit suitable for thick metal?
The product information calls for low RPM and flood coolant when machining thicker metals, so it is presented as a light-duty option rather than an unrestricted choice for thick stock.