How to Choose the Right HSS Bit for the Material, Hole and Drill

What “high speed drill bit” actually means

In product catalogs, a high speed drill bit usually means a drill bit made from high-speed steel, abbreviated HSS. The term describes the cutting-tool material; it is not an instruction to run the drill at maximum RPM.

HSS is a family of alloy tool steels that retains useful hardness at elevated cutting temperatures better than ordinary carbon steel. The exact composition varies, so HSS should not be treated as one uniform grade with a universal temperature limit.

M2 is commonly marketed as the general-purpose HSS grade. It is a practical starting point for routine drilling in materials such as aluminum, mild steel, wood and plastic. A package marked only “HSS,” however, does not necessarily confirm that the bit is M2. Some manufacturers disclose the grade; others do not. Sundi identifies M2 as a common general-purpose grade and distinguishes it from cobalt-alloyed M35 and M42 HSS in its guide to HSS drill bits.

The phrase “high speed” is historical and comparative. It reflects the tool steel’s ability to keep cutting under hotter conditions than basic carbon-steel tooling. Suitable operating speed still depends on:

• Bit diameter
• Workpiece alloy and hardness
• Hole depth
• Point and flute geometry
• Drill type and available torque
• Lubrication and cooling
• Rigidity and alignment

Heat matters because drilling combines cutting, friction and chip movement in a confined space. If the edge rubs rather than cuts, chips remain packed in the flutes, or rotational speed is unsuitable for the material and diameter, heat can build quickly. HSS tolerates cutting heat better than ordinary carbon steel, but the edge can still discolor, lose sharpness or wear prematurely.

As a quick orientation:

• Standard HSS: the versatile general-purpose option.
• Cobalt-alloyed HSS: intended for more demanding metal work where heat and wear are greater concerns.
• Carbide: harder and more brittle, with greater sensitivity to runout, vibration and side loading.

Do not assume every item in a retailer’s “high speed drill bit” category is a conventional HSS twist drill. Retail categories may also contain cobalt bits, step drills, countersinks, drill-and-tap tools, cutting fluid, gauges and adapters. Specialty sellers list HSS products in stubby, jobber, aircraft-extension, extra-long, reduced-shank and hex-shank formats, illustrating how broad the category can be (Drill Bit Warehouse HSS category).

Decode HSS, cobalt, titanium and other package labels

Drill-bit packaging often places unlike specifications side by side. “M35,” “ground,” “titanium,” “black oxide” and “split point” describe different attributes.

Separate the label into these questions:

1. Alloy grade: Is the base material M2, M35, M42 or unspecified HSS?
2. Cobalt content: Is cobalt alloyed throughout the steel?
3. Manufacturing method: Is the bit rolled or ground?
4. Coating: Does it have TiN or another specified coating?
5. Surface finish: Is it bright, black oxide or another finish?
6. Point geometry: Is it a conventional point, split point or another design?
7. Visible color: Does the manufacturer explain what produced it?

Color alone cannot answer the other questions. Gold, black or silver appearance does not prove a particular alloy, coating, manufacturing method or quality level.

HSS and M2

“HSS” identifies the material family. M2 identifies a particular alloy grade commonly positioned for general-purpose drilling. Standard HSS or disclosed M2 is usually a sensible baseline when the job does not involve especially difficult metal or sustained heat.

Do not assume every inexpensive HSS bit is M2. If the grade matters, find it in the technical data rather than inferring it from price, color or words such as “premium.”

M35 and M42 cobalt HSS

A cobalt bit is commonly made from cobalt-alloyed high-speed steel, not ordinary HSS covered by a thin cobalt coating. Because cobalt is part of the alloy, sharpening does not expose a completely different base material in the way that grinding through a surface coating does.

Sundi specifies M35 as HSS containing 5% cobalt and M42 as HSS containing 8% cobalt (Sundi HSS guide). Manufacturers position these grades for stainless steel, harder steels and tough alloys.

The practical tradeoff is that cobalt HSS is generally more expensive and more brittle than standard HSS. Its positioning for demanding work does not make it immune to poor alignment, side loading, a damaged cutting edge or unsuitable operating conditions. Nor do the cobalt percentages alone establish that one bit will outperform another without comparable geometry, quality and testing.

HSS-R and HSS-G

These labels describe manufacturing approaches, not cobalt content:

• HSS-R: commonly denotes a roll-formed or rolled drill.
• HSS-G: commonly denotes a ground drill.

Manufacturers and tool educators often position rolled bits as economical general-purpose products and ground bits as more precisely finished products. Those labels do not establish the alloy grade, coating, point accuracy or performance in a particular workpiece. The terminology is summarized in this HSS drill-bit overview.

Titanium and TiN

TiN means titanium nitride, a coating applied over a base tool material. A package saying “titanium” should not be interpreted as meaning the entire drill bit is solid titanium.

The coating and base alloy should be identified separately. A product may be described as TiN-coated HSS without disclosing the underlying HSS grade. Sharpening removes the coating from the reground cutting region, although coating may remain elsewhere on the bit.

Bright and black oxide

“Bright” and “black oxide” are finish descriptions rather than complete alloy specifications. A bright bit may be uncoated and polished; a black finish may reflect a surface treatment. Neither term, by itself, establishes M2 steel, cobalt content, point accuracy or durability.

Label	What it describes	Typical positioning	Advantages or useful traits	Limitations	Verify on the package
Standard HSS or M2	Tool-steel family or disclosed alloy grade	General-purpose drilling	Versatile and comparatively economical	May wear quickly in difficult or heat-intensive metals	Exact alloy, materials, dimensions and point
HSS-R	Rolled manufacturing method	Economical general-purpose work	Widely available	Does not prove alloy, precision or coating	Base alloy, point and finish
HSS-G	Ground manufacturing method	General-purpose or metal-cutting work	Manufacturing label may indicate a ground finish	Does not mean cobalt or guarantee precision	Alloy, tolerances, point and intended material
TiN-coated HSS	Surface coating over a base tool material	Coated general-purpose or production tooling	Coating remains on surfaces that are not reground	Sharpening removes it from the reground edge	Base alloy, genuine coating specification and sharpening guidance
M35	Cobalt-alloyed HSS	Stainless steel and demanding metal work	Positioned for improved hot-hardness and wear demands	More expensive and generally more brittle	Grade, geometry and rated materials
M42	Cobalt-alloyed HSS	Tough alloys and demanding cutting	Positioned for demanding metal applications	Cost, brittleness and setup sensitivity	Grade authenticity and machine requirements
Carbide	A different, very hard cutting-tool material	Difficult, abrasive or hard materials	High hardness and wear resistance	Brittle and sensitive to vibration and side loading	Solid or tipped construction, machine and workpiece rating

This is a category-level comparison. It does not establish universal advantages in tool life, drilling speed or temperature resistance. Those outcomes require controlled testing of comparable bits under the same conditions.

Choose the bit material for the workpiece

Start with the workpiece, but do not stop at a broad label such as “steel.” Alloy, hardness and heat-treatment condition can substantially affect drillability. Geometry, bit quality, rigidity and technique also influence the result.

Workpiece	Practical starting point	When to choose another format or material	Main consideration
Wood	Standard HSS twist bit for utility holes	Brad-point, auger, spade, Forstner bit or hole saw for a more specialized hole	A metal-style twist bit may not provide the desired finish
Plastic	Sharp standard HSS bit	Plastic-specific geometry where the manufacturer recommends it	Control heat and support the work appropriately
Aluminum	Sharp standard HSS or disclosed M2	A manufacturer-specified coating or geometry for the alloy and production need	Keep chips evacuating from the flutes
Brass	Standard HSS with suitable geometry	Manufacturer-specified geometry for the material	Secure workholding and controlled breakthrough
Copper	Standard HSS	A specialty format for the particular shape or sheet thickness	Match the tool to the form of the workpiece
Mild steel	Standard HSS or M2	Cobalt HSS for repeated work or greater wear demands	Match speed and feed to diameter and material
Sheet metal	HSS twist bit for suitable small holes; HSS step bit for graduated diameters	Hole saw or another sheet-metal cutter for larger holes	Observe the tool’s material and thickness limits
Cast iron	Manufacturer-approved HSS or cobalt bit	Carbide or another specified tool for difficult grades	Confirm the cast-iron grade and tool rating
Stainless steel	Consider M35 or M42 cobalt HSS for repeated or difficult holes	Carbide or a specialty cutter where the material and setup justify it	Avoid rubbing; maintain alignment and rigidity
Harder steel	Cobalt HSS only where the manufacturer rates it for the workpiece	Carbide or specialized tooling in a suitable setup	Confirm actual hardness rather than relying on a broad alloy label
Concrete, brick or block	Purpose-made carbide-tipped masonry bit	SDS or another masonry system where required	An ordinary HSS twist bit is not a masonry bit

Manufacturers commonly position conventional HSS for materials including wood, plastic, aluminum, brass and mild steel. IRWIN, for example, lists metal-drilling products for materials ranging from mild steel and stainless steel to cast iron, aluminum, brass, copper and plastic. That catalog is evidence of manufacturer positioning, not proof that every listed product performs equally in every material (IRWIN metal drill-bit catalog).

A standard HSS twist drill can make holes in wood, but a wood-specific design may be more appropriate:

• Spade bit: for fast, relatively rough larger holes.

• Hole saw: for a large diameter without removing the entire core.

Its usefulness still depends on the manufacturer’s stated material and thickness limits.

Stainless steel and harder alloys

Standard HSS is not physically incapable of drilling every form of stainless steel, but stainless should be treated as a demanding application. Results depend on the stainless grade and condition, hole size, geometry, sharpness, speed, feed, lubrication and machine rigidity.

For repeated or difficult stainless work, consider M35 or M42 cobalt HSS. Cobalt-alloyed HSS is positioned for greater hot-hardness and wear demands, but the label cannot guarantee success. A dull or poorly supported bit may fail regardless of alloy grade.

One user-generated discussion of stainless drilling emphasizes maintaining chip-forming feed and selecting speed for the material and diameter rather than assuming that the lowest available drill-press setting is automatically correct. The advice is anecdotal rather than a controlled comparison, but it also warns that continued rubbing can add heat and may work-harden the surface (Home Improvement Stack Exchange discussion).

If the bit stops producing chips, stop and inspect the setup. Continuing to spin against the same spot can make a difficult operation worse.

When carbide enters the decision

Carbide is generally harder and more brittle than HSS.

It is too broad to say carbide can be used only in CNC machinery. Carbide tools exist in different constructions for different machines. It is equally unsafe to assume that every carbide bit is suitable for a handheld drill. Follow the tool manufacturer’s machine and workpiece requirements.

Concrete and masonry

An ordinary HSS twist drill is not a substitute for a masonry bit. Confirm whether the selected system calls for rotary-only drilling, hammer action or an SDS-type tool.

Match point, length and shank to the drilling setup

Once the material is settled, inspect the bit’s physical design:

• Cutting lips: the edges that remove material.
• Point: the tip geometry that begins and guides the cut.
• Flutes: spiral channels that form part of the cutting geometry and carry chips.
• Flute length: the grooved section available for cutting depth and chip movement.
• Overall length: the full tip-to-shank-end dimension.
• Body diameter: the nominal cutting diameter.
• Shank: the section held by the chuck or driver.

Together, these features determine whether the bit can reach the hole, fit the tool and remain sufficiently rigid.

118-degree versus 135-degree points

A 118-degree conventional point is a common general-purpose geometry. A 135-degree split point is also offered for metal drilling and may require less thrust or resist startup walking when accurately made and used in an appropriate setup.

Neither angle is universally superior. Point quality, lip symmetry, web thickness, workpiece material and machine alignment all matter. IRWIN lists both 118-degree conventional and 135-degree split-point options in its metal-drilling range. Century separately claims that its 135-degree quick-cut point is self-centering and reduces walking; that is a manufacturer claim rather than an independent comparative result (Century HSS specifications).

A split point cannot compensate for a bent bit, loose chuck, unsupported workpiece or severe runout. A sharp conventional point may work well when the location and setup are controlled.

Length formats: reach versus rigidity

From shortest to longest, common descriptions include:

1. Stubby or screw-machine length
2. Mechanics length
3. Jobber length
4. Aircraft-extension length
5. Extra-long length

Exact dimensions vary with diameter and manufacturer. These are relative format descriptions, not substitutes for checking flute and overall length.

Choose stubby or mechanics length when access permits and control is important. Jobber length is the common general-purpose format, but not every HSS twist drill is jobber length.

Aircraft-extension and extra-long bits solve reach problems behind obstructions or inside assemblies. Use only as much length as the operation requires.

Shank styles and chuck fit

Retail catalogs also classify bits with three-flat shanks and hex shanks.

This solves a fit problem only. It does not increase the motor’s power, torque or ability to control a large cutter.

Before buying, check:

• Maximum chuck opening
• Actual shank diameter
• Round, three-flat, hex or other shank style
• Required overall and flute reach
• Visible runout after chucking
• The bit maker’s intended machine or holder
• The drill manufacturer’s accessory and capacity guidance

Select the right size and bit format

HSS drills are sold in four common sizing systems:

• Fractional inch: sizes such as 1/16, 1/8 and 1/4 inch.
• Metric: dimensions expressed in millimeters.
• Number: numbered sizes used for smaller incremental diameters.
• Letter: lettered sizes forming another sequence of inch-based diameters.

Fractional catalog dimensions can also be expressed as decimals:

Fractional size	Decimal equivalent
1/16 inch	0.0625 inch
1/8 inch	0.1250 inch
3/16 inch	0.1875 inch
1/4 inch	0.2500 inch

These equivalents appear in a commercial HSS jobber-drill catalog (American Integrated Supply HSS catalog). The same catalog illustrates why cutting diameter does not determine every other dimension: overall length varies by size, and extracted catalog measurements can contain malformed units.

They are useful when a drawing, clearance requirement or threading operation calls for a more precise diameter. For a threaded hole, consult a verified chart for the exact thread standard and required engagement instead of inferring the tap drill from a general product catalog.

Twist, step and specialty formats

A conventional twist bit makes one nominal diameter and is the default for many ordinary holes. Other products sold beside HSS twist drills serve different purposes:

• Step drill: makes a sequence of progressively larger diameters, generally in thin sheet within stated limits.

• Left-hand bit: cuts in the opposite rotational direction for specialized machining or extraction workflows. It is unrelated to whether the operator is left-handed.

• Countersink: shapes the mouth of a hole for a fastener head or deburring task.

• Hole saw or annular-style cutter: removes a ring rather than converting the full hole volume into chips.
• Reduced-shank drill: provides a larger cutting diameter while fitting a smaller chuck.
• Hex-shank drill: provides compatibility with an appropriate holder.

Choose a stubby bit when limited clearance and greater practical rigidity matter. Choose an aircraft-extension bit when a standard bit cannot reach the hole. Choose a reduced-shank bit when the required cutting diameter exceeds the chuck opening, but only after checking the drill and accessory manufacturers’ capacity guidance.

Never assume two bits with the same cutting diameter share the same overall length, flute length, point geometry or shank. Verify the manufacturer’s specification. If a catalog measurement appears malformed or implausible, check the original documentation rather than silently correcting it.

Finally, size the finished hole, not merely the fastener. Clearance, close-fit, pilot and tap-drill holes can require different diameters for the same nominal fastener.

Buy one bit, a set, or a specialty tool

Buy an individual replacement bit when:

• One known size is broken or worn.
• You use one diameter much more often than the others.
• Your existing set covers the remaining sizes.
• You need a particular alloy, point, length or shank.
• Replacement singles are available for your index.

Buy a set when you regularly need a range of diameters. Common set structures include fractional, metric, number, letter and mixed assortments.

Piece count should not drive the decision by itself. A large assortment may contain sizes you rarely use or may disclose little about alloy and geometry. A smaller set containing the required diameters—and allowing heavily used sizes to be replaced individually—may be more practical.

Retail categories show individual HSS bits and sets across multiple piece-count ranges, but availability is not performance evidence. Application filters for stainless steel, cast iron or sheet metal likewise do not prove that every filtered product will perform well in those materials (Home Depot HSS twist-bit category).

Evaluate a set by:

• Disclosed alloy grade
• Useful size coverage
• Availability of replacement singles
• Point geometry
• Shank compatibility
• Intended workpiece materials
• Length format
• Legible size markings
• Storage that keeps sizes organized and protected
• Manufacturer operating and sharpening guidance

Words such as “professional” and “premium” are positioning, not test results. Color is not a quality grade. Price can reflect material, manufacturing, distribution, packaging or brand position, but it is not direct evidence of durability.

When a specialty tool is the better purchase

Choose a step bit instead of several large twist drills when you need multiple listed diameters in suitably thin sheet. Choose a long bit only for a genuine reach problem and a stubby bit when ordinary length creates access or rigidity difficulties.

A hex shank addresses holder compatibility; a reduced shank addresses chuck capacity. Neither label determines the bit’s alloy or material rating.

For large holes, consider whether a hole saw or another purpose-made cutter is more appropriate than a large twist drill. For clean woodworking, a brad-point or Forstner bit may produce a more suitable hole than an HSS metal-drilling bit.

Package-reading checklist

Before purchase, confirm:

• Exact base material or alloy grade
• Whether “titanium” or a similar term means a coating
• Whether black or bright describes only the finish
• Nominal diameter and decimal equivalent where relevant
• Overall length and flute length
• Point angle and split-point status
• Shank diameter and style
• Intended workpiece materials
• Tool or machine compatibility
• Manufacturer guidance for speed, feed, lubrication and sharpening

There is no defensible “best” brand or product here without controlled head-to-head testing. Buy the specification that fits the work rather than the most aggressive package claim.

Use an HSS drill bit without overheating or breaking it

Begin with the instructions supplied for the drill, bit and workpiece. Wear suitable eye protection, secure the work with an appropriate vise or clamping method, and keep clear of the rotating tool. Commercial metal-drilling guidance also emphasizes eye protection, variable-speed control, suitable pressure and lubrication (TTP Hard metal-drilling guide).

There is no single correct RPM for every HSS bit. Suitable speed depends on:

• Workpiece alloy and hardness
• Bit diameter
• Hole depth
• Drill type and available torque
• Point and flute geometry
• Lubrication or cooling conditions
• Whether the cut is continuous or interrupted

As a directional rule, larger bits and demanding metals generally require more conservative rotational speed than small bits in easier-cutting materials. Use a material- and diameter-specific chart from the bit or machine manufacturer when exact settings are required.

Feed the edge so it cuts

The bit needs controlled axial feed so its cutting lips remove material and form chips. Too little feed may leave the edge sliding over the surface, creating heat without making useful progress.

More pressure is not automatically better. Aim for stable cutting rather than either polishing the surface or forcing the tool.

Chip formation and sound are useful clues, not definitive diagnoses.

Maintain alignment

Keep the bit aligned with the intended hole axis. Avoid side loading, especially with:

• Small-diameter bits
• Brittle cobalt or carbide tooling
• Aircraft-extension and extra-long bits
• Bits projecting farther from the chuck than necessary

Before contacting the work, confirm that the bit is seated correctly and does not show obvious bending or excessive runout.

Use suitable lubrication and clear chips

A suitable cutting fluid can help reduce friction and heat in metal drilling. The correct product depends on the workpiece, tool and operating environment; no single fluid is appropriate for every alloy.

Follow the drill or machine manufacturer’s procedure, and do not reach toward rotating chips.

It is not required for every operation, and the evidence does not support one universal pilot diameter.

Pause for cooling and inspection if the bit:

• Stops producing chips
• Develops abnormal discoloration
• Generates excessive heat
• Squeals persistently
• Shows chipped cutting lips
• Begins flexing or wandering

Handheld drill versus drill press

With a handheld drill, secure workholding and alignment require particular attention because the operator controls both tool angle and feed. Use the drill only within the limits stated by its manufacturer.

The lowest available spindle speed is not automatically correct; bit diameter, material and manufacturer guidance still determine the setting.

Troubleshoot dulling, walking, squealing and poor holes

Use the symptom to identify possibilities rather than immediately buying a harder bit.

Symptom	Possible causes to check	Practical response
Bit walks at startup	Dull or unsuitable point, inaccurate location, poor alignment, excessive projection	Inspect the point, improve location and rigidity, and shorten unsupported reach
Squealing	Rubbing, dull edge, unsuitable speed or feed, misalignment	Stop and inspect before continuing
No chips form	Dull bit, rubbing, wrong rotational direction, damaged surface or unsuitable tool	Verify direction, tool condition and material rating
Cutting edge discolors	Excess heat, unsuitable speed, rubbing or packed chips	Pause, inspect and correct the cause
Flutes pack with chips	Inadequate chip evacuation or a deep uninterrupted cut	Retract under control and clear chips using the machine maker’s procedure
Hole is oversized or rough	Runout, unequal cutting lips, bent bit, loose work or chatter	Recheck seating, workholding and cutting geometry
Bit dulls rapidly	Wrong tool material, heat, abrasive workpiece or unsuitable technique	Verify the workpiece and correct speed, feed, lubrication and alignment
Bit flexes or wanders	Excessive bit length, side pressure or inadequate support	Use a shorter bit if possible and improve support
Bit breaks	Side loading, packed chips, excessive feed, breakthrough loading, brittleness or fatigue	Stop and identify the likely cause before fitting another bit

Walking at startup

Check whether the point is sharp and symmetrical, the location is marked appropriately and the bit approaches squarely. Reduce unnecessary projection from the chuck. A well-made 135-degree split point may help resist walking, but it is not a cure for runout, poor location or a flexible setup.

Squealing or failure to produce chips

Squealing or a lack of chips may indicate sliding contact rather than effective cutting. The bit may be dull, misaligned, turning at an unsuitable speed or facing a material outside its practical rating.

Stop and inspect. Confirm the drill is turning in the correct direction, the cutting lips remain intact and the bit specification matches the workpiece.

Packed flutes

Do not force the tool deeper when the flutes are packed. Stop safely, retract under control and clear the obstruction according to the equipment manufacturer’s procedure. Packed chips impede chip evacuation and can contribute to heat and breakage.

Rough or oversized holes

Inspect the bit for bending and uneven lip wear. Check tool seating, runout and workholding.

Long bits amplify alignment errors. If the extra reach is unnecessary, use a shorter format. If it is unavoidable, minimize side pressure and improve support.

Rapid dulling in stainless steel

Do not diagnose a stainless-steel problem from the alloy label alone. Even cobalt HSS can dull quickly if it rubs, overheats, runs out of alignment or encounters a hardened surface.

If chip formation stops, stop drilling. Repeatedly polishing the same spot adds heat and may work-harden the surface. The correct response to an already hardened area depends on the material, hole and available machinery; there is no universal recovery procedure.

Sharpen or replace?

HSS twist bits can generally be resharpened if enough sound material remains and the correct geometry can be restored. Both cutting lips need balanced length, angle and relief. A poor grind may cause walking, uneven loading or an oversized hole.

Sharpening a coated bit removes coating from the reground cutting region. The bit may remain usable, but its behavior should not be assumed identical to that of a new coated edge.

Replace a bit if it is:

• Cracked
• Bent
• Heavily chipped
• Too short to grind or hold safely
• Impossible to restore to balanced cutting geometry

Use this decision sequence:

1. Verify the workpiece: identify its material, condition and likely difficulty.
2. Verify the bit: confirm alloy, diameter, point, length and intended application.
3. Inspect the edge: look for dulling, chipping, asymmetry, coating loss or bending.
4. Correct the setup: address workholding, alignment, rigidity, speed, feed, lubrication and chip clearing.
5. Sharpen or replace: regrind only when the bit is sound and balanced geometry can be restored.

Frequently asked questions

Is a high speed drill bit the same as an HSS drill bit?

Usually, yes. In catalogs, “high speed drill bit” normally refers to a high-speed-steel drill bit, or HSS bit. It does not mean the drill should always run at its highest speed.

Check the complete description because retail categories can mix ordinary HSS twist drills with cobalt-alloyed HSS, coated bits, step drills, countersinks and related accessories. “HSS” identifies a family of tool steels, not one exact alloy or design.

Can a standard HSS drill bit drill stainless steel?

It may drill some stainless steel under suitable conditions, particularly when the bit is sharp and the setup is rigid. Stainless is nevertheless a demanding application, and ordinary HSS is not the ideal choice for every grade or condition.

For repeated or difficult work, consider M35 or M42 cobalt HSS. Regardless of alloy, use material- and diameter-appropriate speed, maintain chip-forming feed, keep the bit aligned and stop if it merely rubs.

Are cobalt drill bits coated, or is cobalt part of the steel?

Cobalt drill bits are commonly made from cobalt-alloyed HSS, meaning cobalt is part of the steel rather than a thin surface coating. This differs from TiN, which is applied over a base tool material.

Because cobalt is alloyed through the bit, normal sharpening does not remove it from the cutting edge. Sharpening a coated bit, by contrast, removes the coating from the reground region.

Is a 135-degree split point better than a 118-degree point?

Not universally. A well-made 135-degree split point may reduce startup walking and required thrust in suitable metal-drilling work. A 118-degree conventional point remains a common general-purpose geometry.

The better choice depends on the material, diameter, grind quality, hole location and setup. Neither point compensates for a dull edge, bent bit, loose workpiece or poor alignment.

Can HSS drill bits be sharpened?

Yes. HSS twist bits can generally be resharpened if they remain straight, uncracked and long enough to grind safely. Both cutting lips must be restored with balanced length, point angle and clearance.

Sharpening removes any surface coating from the reground cutting area. Replace rather than sharpen a bit that is bent, cracked, heavily chipped or impossible to return to balanced geometry.

The compact decision path is straightforward: identify the workpiece and its difficulty, choose standard or cobalt-alloyed HSS accordingly, and then match the diameter, point, length and shank to the hole and drill. Use controlled speed, chip-forming feed, secure workholding and suitable lubrication. The HSS label is only one part of the decision, and harder or more expensive tooling is not automatically better for every setup.