118 vs 135 Degree Drill Bit: Which to Use (Split-Point Explained)

A 118-degree drill bit has the sharper, more pointed tip and is the right default for wood, plastic, and drywall — a 135-degree bit needs its self-centering split point, not the wider angle alone, to resist walking in steel and cast iron. Grabbing the wrong one dulls bits faster and can wander off-mark on a precision hole. This guide covers the real angle geometry, material matchups, coatings, and when the two genuinely cross over.

Understanding Drill Bit Degrees: The Basics

Drill bits cut through material with the angle ground into their tip, called the point angle or included angle. A smaller point angle comes to a sharper, more pointed tip; a larger point angle is flatter and more blunt — think of sharpening a pencil to a fine point (small angle) versus a stubby, rounded point (large angle). That geometry directly affects how much pressure you need, how the bit clears debris (“swarf”), and whether it starts drilling exactly where you put it.

What Is the 118° Drill Bit Angle?

The 118° bit is the standard twist bit included with most drill sets. Being the smaller of the two angles, it has the sharper, more pointed tip — that point bites in and starts cutting on its own, without a center punch, on wood, plastic, and drywall.

Key Characteristics of 118° Drill Bits:

• Angle: 118 degrees (the smaller, sharper-tipped angle).
• Appearance: Tip looks noticeably more pointed than a 135° bit.
• Self-starting: Bites in on its own on softer material — no punch mark needed.
• Best For: Wood, plastic, drywall, and thin, soft sheet metal.

What Is the 135° Drill Bit Angle?

The 135° bit uses a flatter, more open point angle than a 118° bit. On its own, a flatter point is actually more prone to skating across a hard, smooth surface — which is exactly why nearly every 135° bit sold for metal is also ground with a split point: two extra bevels cut into the chisel edge at the very tip. That split point is what lets the bit stay centered and start cutting immediately on steel, without a pilot hole or a punch mark.

Key Characteristics of 135° Drill Bits:

• Angle: 135 degrees (the larger, flatter angle).
• Appearance: Tip looks flatter and more blunt than a 118° bit.
• Anti-walking: Comes from the split-point grind, not the wide angle alone.
• Best For: Steel, cast iron, and other hard or work-hardening metals.

📊 A split point is ground as two extra bevels into the chisel edge — that extra grinding step is exactly why true split-point bits cost noticeably more and are harder to resharpen by hand than a plain 118° point. — Source: Drill Doctor

118° vs 135° Drill Bit: The Material Matchup

The biggest deciding factor in choosing between an 118° and 135° drill bit is the material you’re drilling into. Using the right bit ensures efficiency, prolongs the life of your drill bit, and gives you a cleaner hole. Let’s dive into which bit is best suited for different substances.

Drilling in Wood and Softer Materials (118° Ideal)

Wood, plastics, and some composite materials are generally considered softer. For these, the 118° drill bit is your go-to. Here’s why:

• Easier Start: The sharp point bites in immediately, so the bit doesn’t skitter across the surface.
• Efficient Chip Evacuation: 118° bits clear wood chips well at a standard drill’s speed.
• Less Heat: Softer materials generate less friction, so the less aggressive cutting action of a 118° bit is perfectly adequate.
• Cost-Effective: Standard 118° bits are generally less expensive and widely available.

When you’re building that awesome bookshelf, crafting a birdhouse, or putting up shelves, your standard twist drill bits are almost certainly 118°. They are the everyday heroes for the vast majority of home DIY projects involving wood and plastics.

Drilling in Metal and Harder Materials (135° Recommended)

When you move to harder materials like steel, aluminum, cast iron, or tough plastics, a plain 118° bit starts to struggle and slide. This is where a split-point 135° bit shines:

• No Walking: The split point self-centers on contact, so it doesn’t skate before it bites.
• No Pilot Hole Needed: Unlike a plain point on hard metal, a split-point bit starts cleanly without a punch mark.
• Less Heat Build-up: A cleaner, faster start means less friction and heat at the point of contact — critical for metal, where excess heat dulls a bit fast.
• Overall Efficiency: Drilling through metal is quicker and takes less force with the correct bit.

For tasks like attaching metal brackets, car repairs, or drilling into pipe, a 135° split-point bit will make your life much easier and deliver cleaner results. Many are also made with coatings like cobalt, titanium, or black oxide to further boost durability in metal.

When Can a 135° Bit Be Used in Wood?

While 118° bits are standard for wood, a 135° split-point bit isn’t unusable in softer materials. Some woodworkers prefer them for specific tasks:

• Starting Holes Precisely: The self-centering split point helps start a hole exactly on a smooth surface without a center punch.
• Drilling Dense Hardwoods: For exotics or very hard hardwoods, a split-point bit’s cleaner start can offer a slight advantage.
• Specialty Bits: Some Forstner bits and step bits use steeper point geometry for specific cutting actions.

For general-purpose wood drilling, though, the 118° remains the more forgiving and common choice, and it’s cheaper to replace.

When Can an 118° Bit Be Used in Metal?

Using a plain 118° bit in metal is generally discouraged, especially for harder metals like steel. A few exceptions and workarounds exist:

• Very Soft Metals: For extremely soft metals like thin aluminum sheeting or copper, an 118° bit can suffice.
• Center-Punch First: Without a split point, an 118° bit needs a punch mark or pilot hole to start straight on metal — skip this and it will walk.
• Lubrication Is Key: If you must use an 118° bit in metal, cutting fluid is essential to reduce friction, keep the bit cool, and prolong its life.
• Not for Heavy-Duty Work: For structural metalwork or thicker gauge steel, an 118° bit is the wrong tool and will likely fail or leave a ragged hole.

Think of it this way: you can drive a screw with a butter knife, but it’s inefficient and likely to damage both. Using an 118° bit on metal without a punch mark is a similar compromise.

“In the shop, a plain 118° bit walks the second it touches painted steel — no amount of downward pressure fixes that without a punch mark first. Swap to a 135° split-point bit and it grabs on contact, no punch needed. That’s the entire reason the split point exists.”

Drill Bit Coatings and Materials: Beyond the Angle

While the 118° vs 135° angle is a primary differentiator, other factors significantly impact drill bit performance, especially when drilling metal. For harder jobs, these matter just as much:

HSS (High-Speed Steel)

This is the most common material for drill bits. HSS bits withstand higher temperatures than standard carbon steel bits, making them suitable for a wide range of materials. Most general-purpose twist drill bits are made from HSS.

Cobalt

Cobalt drill bits are HSS with a percentage of cobalt added, which significantly increases hardness and heat resistance. Cobalt bits excel at drilling hard, abrasive metals like stainless steel and cast iron, and they’re almost always paired with a 135° split point.

Titanium Nitride (TiN) Coating

A thin, gold-colored coating that’s extremely hard and slippery. It reduces friction, helping the bit cut cooler and faster while extending its life. TiN-coated bits work well on both 118° and 135° bits, but the benefit shows up most on 135° bits used in metal.

Black Oxide Coating

A chemical treatment that gives bits a black, non-reflective finish, some corrosion resistance, and improved lubricity. Black oxide isn’t as hard as titanium nitride, but it’s effective for general-purpose drilling in metal and wood, and it’s generally more affordable.

Carbide Tipped

These bits have a solid carbide tip brazed onto a steel shank. Carbide is exceptionally hard and drills through very tough materials, including brick, tile, concrete, and hardened metals. Its effectiveness has more to do with carbide’s inherent hardness than the 118° vs 135° angle.

Comparing 118° and 135° Drill Bits: A Quick Table

To help you quickly decide, here’s a comparison table:

Feature	118° Drill Bit	135° Drill Bit
Angle	118 degrees (smaller, sharper point)	135 degrees (larger, flatter point)
Tip Appearance	Sharper, more pointed	Flatter, more blunt — usually paired with a split point
Best For	Wood, plastic, composites, drywall, soft metals	Hard metals (steel, cast iron, stainless), tough plastics
Starts Without a Punch Mark?	Yes, on soft material	Yes, if split-point ground
Heat Generation (in metal)	Higher — tends to rub instead of cut	Lower, when split-point ground
Risk of Walking (on hard metal)	Higher without a pilot hole	Lower, only if split-point ground
Common Use	General home DIY, woodworking	Metalworking, demanding materials
Availability	Very common, widely available	Common, especially for metalworking
Cost & Sharpening	More affordable, easy to hand-sharpen	Costs more; split point is hard to hand-sharpen

How to Choose the Right Drill Bit for Your Project

Making the correct choice is simpler than it seems. Follow these steps:

1. Identify Your Material: Are you drilling wood, plastic, drywall, aluminum, steel, or something else?
2. Consider the Hardness: Softer porous materials (wood, drywall) do well with 118° bits. Dense, hard materials (steel, cast iron) need a 135° split-point bit.
3. Think About Precision: Starting a hole precisely on a smooth surface, especially metal, favors a 135° split-point bit’s self-centering tip.
4. Evaluate Bit Type: Standard twist bit? Spade bit? Masonry bit? The 118°/135° rule applies most directly to standard twist bits.
5. Check for Coatings: If drilling metal regularly, a cobalt, TiN, or black-oxide coated bit boosts performance and longevity regardless of angle.
6. When in Doubt on Metal, Go 135° Split Point: If you’re unsure and it’s metal, a split-point 135° bit is almost always the safer, more effective choice.

For example, if you’re assembling IKEA furniture (wood and particle board), standard 118° bits are perfect. If you’re drilling a pilot hole in a metal frame for a TV mount, a 135° split-point bit (preferably cobalt or coated) is the better choice.

Essential Accessories for Drilling

Having the right drill bit is only part of the equation. To ensure successful and safe drilling, consider these tools and accessories:

Drill Bit Sharpeners

Even the best drill bits dull with use. A dedicated drill bit sharpener can save you money, though note that a split-point 135° grind is much harder to restore by hand than a plain 118° point.

Cutting Fluid or Lubricant

When drilling into metal, cutting fluid is essential. It reduces friction and heat, which helps prevent the drill bit from overheating, dulling, and breaking, and it helps clear away metal shavings.

Center Punch

For precise hole placement, especially in metal and hard plastics, a center punch is invaluable. Strike it with a hammer to create a small indentation that guides the bit’s tip and stops it from walking. A true split-point 135° bit reduces the need for a center punch versus a plain 118°, but it’s still good practice for critical locations.

Drill Press Vice

If you’re drilling multiple holes in metal parts or need extreme accuracy, a drill press vice is a must. It securely holds your workpiece, preventing it from spinning, which is crucial for safety and straight holes.

Safety Glasses

This is non-negotiable. Always wear safety glasses when drilling. Metal shavings, wood chips, or broken bit fragments can fly at high speed. According to the Occupational Safety and Health Administration (OSHA), proper eye protection is required in environments where there is a hazard from flying particles.

Work Gloves

While you want good grip on your tools, heavy-duty work gloves can protect your hands from sharp edges and debris, especially when handling metal workpieces.

Common Pitfalls to Avoid

Even with the right bit, beginners can fall into a few traps. Here are common mistakes to steer clear of:

• Using the Wrong Bit: Forcing an 118° bit into hard steel without a punch mark will likely result in a broken bit, a damaged workpiece, and a lot of frustration.
• Assuming Any 135° Bit Resists Walking: The anti-walking benefit comes from a genuine split-point grind, not just a 135° angle stamped on the box — check the listing specifically says “split point.”
• Drilling Too Fast: Excess speed generates heat, which dulls bits quickly and can even melt plastics. Match drill speed to the material and bit size — slower for larger bits and harder materials.
• Not Using Lubrication (for Metal): Skipping cutting fluid when drilling metal is a surefire way to overheat and ruin your bits.
• Applying Too Much Pressure: Let the drill bit do the work. Forcing it can break the bit, slip the workpiece, or create an oversized, ragged hole.
• Not Securing the Workpiece: A workpiece that spins or moves while drilling is dangerous and produces inaccurate results. Always clamp it down.

Frequently Asked Questions

What is the main difference between a 118° and 135° drill bit?

The angle ground into the tip. A 118° bit has the smaller, sharper point and works best in wood, plastic, and drywall. A 135° bit has a flatter point and is built for hard metals like steel and cast iron, usually paired with a self-centering split point.

Does a 135-degree drill bit really resist walking better than a 118-degree bit?

Only if it’s ground with a split point. The 135° angle by itself is flatter and actually more prone to skating on a hard surface. The anti-walking behavior comes specifically from the split-point grind — two extra bevels cut into the chisel edge — which is why almost every 135° bit sold for metal is labeled “split point.”

Can I use a 135-degree drill bit on wood?

Yes. A 135° split-point bit works fine in wood and can even help start a precise hole on a smooth surface without a center punch. It’s just not necessary for general wood drilling, where a cheaper 118° bit performs just as well.

What drill bit angle is best for stainless steel?

A 135° split-point bit in cobalt (M35 or M42 alloy), not a plain HSS bit. Stainless work-hardens quickly, so the combination of a self-centering split point and cobalt’s heat resistance keeps the bit cutting instead of rubbing and dulling.

Is split point the same thing as 135 degree?

No. The degree is the point angle; split point is a separate grinding feature that adds two extra bevels to the chisel edge. Most split-point bits happen to use a 135° angle, but the angle alone doesn’t guarantee a bit is split-point — check the product listing for the words split point specifically.

Do I still need a center punch with a 135-degree split-point bit?

Usually not for general holes — that’s the point of the split-point design. For critical, precisely located holes in metal, though, a center punch mark is still good practice as a backup, especially on curved or angled surfaces where even a split point can drift slightly.

Bottom line: match the bit to the material, not just the number on the label. A sharp 118° bit handles wood, plastic, and drywall without fuss; a genuine 135° split-point bit — ideally in cobalt for the hardest alloys — is what actually stops a bit from walking in steel. Check the listing for “split point,” not just the degree, before you buy.