Yes, you can drill out a broken drill bit, but it requires patience, the right tools, and a careful approach. This guide provides a proven solution for removing stubborn, broken bits from your workpiece.
Ever been in the middle of a project, feeling good, and then… snap! A drill bit breaks off inside your material. It’s frustrating, isn’t it? You’ve got a hole that needs drilling, but now there’s a metal shard stuck right where you need it. Don’t worry, this is a common problem for DIYers, and thankfully, there’s a way to fix it. You don’t have to scrap your project or live with a useless hole. We’ll walk you through a reliable method to get that broken bit out so you can get back to building, hanging, or assembling. Let’s tackle this together!
Why Do Drill Bits Break?
Drill bits are tough, but they aren’t invincible. Understanding why they break can help prevent it from happening again. Here are some common culprits:
- Using the Wrong Bit for the Material: A standard HSS (High-Speed Steel) bit might struggle with hardened steel, leading to excessive heat and breakage. Using bits designed for specific materials is crucial.
- Excessive Speed or Pressure: Pushing too hard or going too fast generates heat and stress. This can cause the bit to bind and snap, especially in tougher materials.
- Dull Bits: A dull drill bit requires more force to cut. This increased pressure can cause it to jam and break.
- Binding or Catching: If the bit isn’t drilling straight or the material shifts, the bit can get caught and snap.
- Improper Cooling: Drilling without coolant in very hard materials can lead to overheating and brittleness, making the bit prone to breaking.
- Manufacturing Defects: Though rare, sometimes a bit might have a weak point from the factory.
Can You Really Drill Out a Broken Drill Bit?
The short answer is yes, but with a big caveat: it depends on the size of the broken bit, the material it’s stuck in, and the tools you have available. It’s not always easy, and sometimes, if the bit is very small or deeply embedded, other methods might be more suitable. However, for many common scenarios, drilling out the broken bit is a perfectly viable solution. It’s about carefully and precisely removing the surrounding material to free the broken piece.
Tools You’ll Need
Before we dive into the steps, let’s gather your arsenal. Having the right tools makes all the difference:
- Safety Glasses: Absolutely essential. Metal shards can fly.
- Work Gloves: Protect your hands.
- Center Punch: To create a starting point for your new drill bit.
- Hammer: To tap the center punch.
- Drill (Corded or Cordless): A variable speed drill is best.
- Drill Bits: Smaller than the broken bit, and preferably made of a harder material like cobalt or carbide.
- Cutting Fluid or Lubricant: Helps the drill bit cut and stay cool.
- Pliers (Needle-nose or Vise-Grips): If any part of the broken bit is sticking out.
- Optional: Dremel or Rotary Tool with a Grinding Bit: For very stubborn bits or to help create a starter divot.
- Optional: Screw Extractor Set: Sometimes an alternative if you can create a good pilot hole.
The Proven Solution: Step-by-Step Guide
This method focuses on drilling a new, smaller hole through the center of the broken bit. This weakens the broken bit enough to either break it apart or allow you to remove the fragments.
Step 1: Assess the Situation and Ensure Safety
First, take a deep breath. Look at how the bit is broken. Is any part sticking out? Is it flush with the surface? Is it at an angle? This will help you plan your approach. Always put on your safety glasses and gloves. Make sure your workpiece is securely clamped down.
Step 2: Try the Simple Approach (If Applicable)
If a small portion of the broken bit is sticking out, try gripping it firmly with a pair of needle-nose pliers or small vise-grips. Gently try to twist and pull it out. Sometimes, a bit of wiggling is all it takes. If it doesn’t budge, don’t force it too much, as you could make it worse. Move on to the drilling method.
Step 3: Center Punch the Broken Bit
This is a crucial step for accuracy. You need to drill as close to the center of the broken bit as possible.
Place the tip of your center punch directly on the very center of the broken drill bit.
Hold the punch firmly and strike the end with your hammer. You don’t need a massive blow, just enough to create a small indentation. This divot will guide your new drill bit and prevent it from wandering off-center.
Step 4: Select Your New Drill Bit
Choose a drill bit that is significantly smaller than the broken bit. Ideally, it should be made of a harder material, like a cobalt drill bit, which can cut through hardened steel more effectively than standard HSS bits. If the broken bit is a standard metal bit, a cobalt bit is your best bet. If the broken bit is already cobalt, you might need a carbide bit, though these are more brittle and require extra care.
Consider the material you are drilling into as well. If it’s soft wood, a standard bit might suffice for drilling the hole around the broken bit. But if the broken bit is in metal, you’ll want a harder bit.
Step 5: Prepare for Drilling
Apply a drop of cutting fluid or lubricant to the center punch mark on the broken bit. This will help the new drill bit cut more smoothly and stay cooler, reducing the risk of further breakage or overheating.
Step 6: Start Drilling
This is where precision and patience come in.
Set your drill to a slow speed. A variable speed drill is ideal here.
Hold the drill as straight and perpendicular to the surface as possible.
Carefully place the tip of your new, smaller drill bit into the center punch mark.
Begin drilling slowly, applying steady, light pressure. Let the drill bit do the work. Avoid pushing too hard, as this can cause the new bit to break or wander off course.
Step 7: Drill Through the Broken Bit
Continue drilling slowly and steadily through the entire length of the broken drill bit. You may need to periodically add more cutting fluid. As you drill, you’ll be creating a hole through the center of the broken bit. This weakens it significantly.
Here’s a table to help you choose the right drill bit for drilling out another bit:
| Material of Broken Bit | Recommended Drill Bit for Removal | Key Considerations |
|---|---|---|
| Standard HSS Steel | Cobalt (HSS-Co) | More heat-resistant and harder than standard HSS. |
| Cobalt (HSS-Co) | Carbide (Tungsten Carbide) | Extremely hard but brittle. Requires very precise drilling and can shatter if chipped. |
| Hardened Steel (e.g., some drill press chucks) | Carbide or Diamond-Coated | Diamond-coated bits are excellent for very hard materials but are typically used with rotary tools. |
Step 8: Remove the Fragments
Once you’ve drilled through the broken bit, the remaining piece should be weakened. You might find that the drilling action has broken the bit into smaller pieces that can be picked out with needle-nose pliers or a small pick. Sometimes, the drilling will create enough of a void that the remaining metal can be tapped out from behind if you have access to the other side of the material.
If the broken bit was in a threaded hole, drilling through it might have destroyed the threads. In this case, you might need to re-tap the hole after removing the fragments.
Step 9: What If It Doesn’t Work? Alternatives and Advanced Tips
If drilling through the broken bit doesn’t free it, or if you’re hesitant to drill further, here are some other options:
- Screw Extractors: After drilling a pilot hole (as described above), you can try using a screw extractor. These tools have reverse threads that bite into the drilled hole. You then turn the extractor counter-clockwise to hopefully back out the broken bit. Make sure the extractor is smaller than the broken bit itself. You can find screw extractor sets at most hardware stores. For guidance on using them, check out resources like Popular Mechanics’ guide on screw extractors.
- Left-Handed Drill Bits: These bits are designed to cut in reverse. As you drill into the broken bit, the reverse action might catch the broken piece and unscrew it. This is often a very effective method.
- EDM (Electrical Discharge Machining): For extremely stubborn or critical parts, EDM is a non-contact machining process that uses electrical sparks to erode the broken bit. This is a professional service and not a DIY solution, but it’s the ultimate method for removal without damaging the surrounding material.
- Grinding (with caution): If the broken bit is sticking out and you have a Dremel or rotary tool with a grinding stone, you can try to carefully grind away the edges of the broken bit. This is best done if you can access it from the side and grind it down to the surface. Be very careful not to damage the surrounding material.
Here’s a quick comparison of methods:
| Method | Pros | Cons | Best For |
|---|---|---|---|
| Drilling Through | Can be effective, uses common tools. | Requires precision, risk of new bit breaking, can damage threads. | Most common scenarios, moderate-sized broken bits. |
| Screw Extractors | Can remove the bit intact if it bites well. | Requires a good pilot hole, extractors can break if misused, might not grip if the bit is too smooth. | When a clean pilot hole can be drilled, and the broken bit isn’t seized too tightly. |
| Left-Handed Bits | Can unscrew the bit as it drills. | Requires specific drill bits, still needs careful drilling. | When you want a method that attempts removal while drilling. |
| EDM | Highly precise, no damage to surrounding material. | Professional service, expensive, not DIY. | Critical components, very hard materials, when other methods fail. |
Preventing Future Breakage
The best solution is often prevention. Here are some tips to keep your drill bits in good shape:
- Use the Right Bit for the Job: Match the bit material and type to the material you’re drilling.
- Maintain Sharpness: Sharpen your drill bits regularly. A sharp bit cuts easier and produces less heat. You can learn more about sharpening at Wood Magazine’s guide.
- Control Speed and Pressure: Start slow and increase speed as needed. Apply steady, consistent pressure. Let the bit cut, don’t force it.
- Use Lubricant: Especially when drilling metal, cutting fluid or oil helps reduce friction and heat.
- Drill Straight: Ensure your drill is perpendicular to the workpiece.
- Clear the Hole: Periodically back the bit out slightly while drilling to clear chips and debris.
Frequently Asked Questions (FAQ)
- Q1: What’s the easiest way to remove a broken drill bit?
- The easiest way, if possible, is to grip the protruding part with pliers and twist it out. If it’s flush or broken off, carefully drilling a smaller hole through the center is the most common DIY solution.
- Q2: Can I use a regular drill bit to drill out a broken drill bit?
- It’s best to use a harder drill bit, like cobalt or carbide, to drill out a broken standard steel bit. A regular bit might struggle and break itself.
- Q3: What if the broken bit is in wood?
- If the broken bit is in wood, it’s generally easier. You can often use a standard drill bit (even slightly larger than the broken bit, but smaller than the intended hole) to drill around the broken piece, or drill through it as described. Sometimes, a sharp chisel can also help dislodge it.
- Q4: How do I prevent damaging the material when drilling out a bit?
- The key is precision. Use a center punch to start in the exact middle. Drill slowly and steadily, using a lubricant. If using a screw extractor, ensure it’s the correct size and don’t force it.
- Q5: My broken bit is very small. What should I do?
- For very small bits (e.g., 1/16 inch or smaller), drilling them out can be extremely difficult. You might have better luck using a very fine pick or needle to try and pry it out, or consider using a screw extractor designed for small fasteners after drilling a pilot hole with a micro-drill bit.
- Q6: Do I need a special drill for this?
- A variable-speed drill is highly recommended for better control. A corded drill often provides more consistent power than a cordless one for tougher jobs like drilling through metal. However, a good cordless drill can also work if used carefully.
Conclusion
Dealing with a broken drill bit can feel like a project-ending disaster, but it doesn’t have to be. By following these steps, using the right tools, and exercising a bit of patience, you can successfully remove that stubborn piece of metal. Remember to prioritize safety, start with the least invasive methods, and don’t be afraid to use harder drill bits or specialized tools like screw extractors if needed. With a little practice, you’ll gain the confidence to tackle this common DIY challenge and keep your projects moving forward. Happy drilling!
