How To Drill Out Rivets: The Complete Technical Guide To Fastener Removal

Drilling out rivets requires matching the drill bit diameter to the specific rivet shank size, stabilizing the workpiece, and applying steady axial pressure at moderate speeds to shear the head without enlarging the factory hole. Mastering this mechanical extraction technique prevents structural damage to surrounding sheet metal in automotive, aviation, and structural fabrication applications.

Pre-Operation & Equipment Checklist

Removing structural blind rivets (often referred to as pop rivets) or solid rivets demands a precise approach to preserve the integrity of the base material. Rushing this operation or using incorrectly sized bits frequently leads to oversized holes, broken drill bits embedded in the substrate, or stripped panels. Setting up a dedicated workspace with proper lighting and safety gear ensures a clean extraction every time.

• Essential Gear, Tools, and Materials:

  
  
  
  • Variable-speed corded or cordless power drill (3/8-inch or 1/2-inch chuck)
  • Cobalt or high-speed steel (HSS) twist drill bits (specifically sized: #30 bit for 1/8-inch rivets, #20 bit for 5/32-inch rivets, and #10 bit for 3/16-inch rivets)
  • Center punch and a small ball-peen hammer
  • Safety glasses and heavy-duty work gloves
  • Needle-nose pliers or a magnetic pick-up tool
  • Cutting fluid or lightweight machine oil
  • Hammer and a small pin punch (for solid rivets or stubborn mandrels)

• Mandatory Prerequisite Knowledge and Standards:

  
  
  
  • Identification of rivet body material (aluminum, steel, stainless steel, or monel) to determine bit durability requirements.
  • Verification that the surrounding structural panel is securely clamped to prevent vibration-induced binding.
  • Familiarity with drill speed control to prevent frictional overheating, which dulls high-speed steel bits instantly.

• Estimated Budget and Duration Benchmarks:

  
  
  
  • Material and tool investment: Twenty to fifty dollars if purchasing dedicated cobalt bits and a center punch.
  • Time commitment: Approximately one to two minutes per individual rivet for standard setups.

Step-by-Step Rivet Extraction Workflow

Step 1: Surface Inspection and Center Punching

Inspect the target rivet to identify its type and overall condition. If the rivet head is painted, corroded, or domed irregularly, the drill bit may skate across the surface and gouge the surrounding metal panel.

1. Clean the immediate area around the rivet head of dirt, grease, or loose paint flakes using a wire brush or scraper.
2. Place the sharp tip of a center punch precisely in the exact center dimple of the rivet head.
3. Strike the back of the center punch firmly once with a ball-peen hammer to create a definitive indentation. This dimple acts as a positive mechanical guide that prevents the drill bit from wandering off-center upon engagement.

Warning: Never attempt to drill a rivet without first center-punching it. Skated drill bits can easily slip and cause severe lacerations or puncture adjacent structural sheet metal.

Step 2: Selecting the Correct Drill Bit Size

Choosing the proper drill bit diameter is the most critical variable in successful rivet removal. Using a bit that is too large destroys the factory hole tolerance, while using an undersized bit leaves the structural shell intact, making extraction impossible.

1. Measure the outer diameter of the rivet flange or consult the fastener specification chart.
2. Select a twist drill bit that matches the inner diameter of the rivet shank, not the outer flange. For standard blind rivets, use a #30 bit for 1/8-inch rivets, a #20 bit for 5/32-inch rivets, and a #10 bit for 3/16-inch rivets.
3. Inspect the chosen drill bit for sharpness and ensure it is firmly secured in the drill chuck with minimal runout.

Step 3: Drilling Out the Rivet Head

With the workpiece stabilized and the correct bit installed, you are ready to shear the fastener head from its load-bearing shank.

1. Apply a single drop of cutting fluid or lightweight machine oil directly onto the center-punched rivet head to reduce friction and thermal buildup.
2. Position the tip of the drill bit squarely inside the center-punch indentation, holding the drill strictly perpendicular (90 degrees) to the mounting surface.
3. Squeeze the drill trigger to engage a slow to moderate rotational speed (approximately 1,500 to 2,000 RPM). Avoid running the drill at maximum velocity.
4. Apply light, consistent axial pressure downward. Let the cutting edges of the bit shear away the metal of the rivet head rather than forcing it through sheer muscle.
5. Listen and watch for a sudden change in pitch and resistance. When the rivet head separates from the shank, stop forward pressure immediately.

Pro-Tip: If the drill bit begins to bind or squeal, pull back slightly to clear out metal shavings and reapply cutting fluid to prevent premature bit dulling.

Step 4: Punching Out the Remaining Shank

Once the head falls away, the remaining cylindrical body (and potentially a steel mandrel piece) remains trapped inside the mating panels.

1. Brush away metal shavings and the detached rivet head from the work area.
2. Select a pin punch that matches the inner diameter of the hole (slightly smaller than the drill bit used).
3. Place the tip of the pin punch against the exposed top of the remaining rivet shank.
4. Strike the blunt end of the pin punch lightly with a hammer to drive the residual sleeve completely through the backside of the joint.
5. Retrieve the fallen slug using a magnetic tool or vacuum to keep the work area free of stray debris.

Rivet Material Properties and Bit Selection Matrix

Common Site Failures and Field Fixes

• Root Cause: The drill bit wanders across the panel surface, scratching the surrounding paint or metal.

  
  
  
  • Actionable Fix: Ensure the center punch mark is deep enough to trap the drill tip, and run the drill at a slower initial RPM while keeping the tool strictly perpendicular.

• Root Cause: The drill bit snaps off flush inside the rivet hole, leaving a hardened steel fragment embedded in the substrate.

  
  
  
  • Actionable Fix: Do not attempt to drill through a broken HSS or cobalt bit with another standard bit. Use a carbide burr in a rotary tool to grind out the broken fragment, or carefully fracture it using a fine-tipped punch and hammer.

• Root Cause: The rivet spins in its hole continuously without the head shearing off.

  
  
  
  • Actionable Fix: The friction between the drill bit and the rivet is causing the entire fastener to rotate. Wedge the backside of the rivet flange with needle-nose pliers, or use a sharp chisel to pry upward slightly on the head while drilling to create upward tension.

• Root Cause: The factory mounting hole becomes enlarged or egg-shaped after drilling.

  
  
  
  • Actionable Fix: Step up to the next fractional or metric rivet size, or install a threaded rivet nut (rivnut) that accommodates a larger grip range and hides the expanded hole profile.

Frequently Asked Questions

What size drill bit do I need for a standard 1/8-inch pop rivet?

For a standard 1/8-inch blind rivet, use a number 30 drill bit, which measures approximately 0.1285 inches in diameter. This provides just enough clearance to slice through the rivet head and hollow core without cutting into the surrounding structural metal hole.

What should I do if the rivet just spins around when I try to drill it?

Spinning rivets occur when the friction of the bit overcomes the grip of the expanded tail. To stop it, wedge the underside of the rivet flange with flathead pliers or apply gentle upward pry bar pressure underneath the head to bind the body against the panel while drilling.

Can I use a standard wood-working drill bit for metal rivets?

No. Wood-working drill bits feature a sharp center brad point and spurs designed to slice wood fibers, which will instantly chip, bend, or break when encountering structural metal rivets. Always use twist drill bits manufactured from high-speed steel, cobalt, or titanium-coated alloys.

How do I prevent my drill bit from breaking when drilling out tough stainless steel rivets?

Stainless steel work-hardens rapidly under frictional heat. To prevent bit breakage, operate your drill at a slow rotational speed, use heavy and consistent feed pressure, and continuously lubricate the cutting zone with specialized cutting oil.

Do I need to clean out the back of the panel after removing a rivet?

Yes. When you punch out the remaining rivet shank, the cylindrical metal slug falls free behind the blind side of the panel. Always clear these discarded slugs using a vacuum or a magnetic pickup tool to prevent rattles, electrical shorts, or surface corrosion inside enclosed box sections.

Equip your toolkit with professional-grade bits and precision punches today to tackle structural fastening teardowns with absolute confidence and pristine finishing results.