What is a Step Drill Bit?

A step drill bit is a conical bit that can create lots of holes of varying diameters using a single bit on tough and soft metal. So deeply learning what is a step drill bit can improve the skill level of a DIYer and increase productivity using the right bit for certain projects.

Today we have discussed on the step drill bit including its key features, advantages, and appropriate use method to offer complete knowledge of this particular drill bit. So, reading the guide will help you apply this specially designed step drill bit to the appropriate project efficiently and get the desired performance.

What is a Step Drill Bit Used for?

A step drill bit is a specially designed bit that can create multiple diameter holes using a single one. This drill bit gradually increases the size of the hole while digging into the hard surface. The shape of the step drill bit is similar to a cone, thus avoid the requirement of changing the drill bit frequently.

The drill bit also has a jagged groove at one side that is used as a cutting edge. Apart from drilling various sizes of holes, a step drill bit is a handy option for enlarging the existing hole. Though the step drill bit is mostly perfect for drilling through tough metal, it can also create a hole in plastic, wood, and other soft surfaces.

Features of the Step Drill Bit

Split Point: The split point tip of a step bit is designed with a thinner cutting point to help the bit catch the work surface. It keeps the bit stable and prevents drift during drilling with higher pressure. Thus, using a step bit doesn’t require a centre punch.

Spiral-Flute: The step drill bit comes with a spiral fluted shape for efficient chip collection and removes them quickly. the feature also helps prevent overheating of the step drill bit and increases its service life. Apart from these, due to removing the chips quickly, the step drill bit makes the drilling process faster than a typical bit and it can remove chips quicker than a straight fluted bit.

CBN: Cubic Boron Nitride (CBN) is a super tough material that has chemical inertness and improved thermal stability. This material is generally used for grinding cutting tools. Therefore, a CBN-coated step bit ensures superior cutting performance over the tough surface.

Chamfer Edge: Once you have reached the required size hole, the chamfered edge of the step drill bit makes the cutting hole burr-free and smooth. All the steps of a step drill bit are designed with the same chamfer angle, making the transition between two-step hardly noticeable.

Step Height: The step height of this drill bit determines how thick metal it can drill. The metal you are planning to drill must be slimmer than the height of the step bit you have chosen. The step drill bit comes with a laser etch mark to let the user identify the step height of the bit.

6 Flat Shanks and Hex Shank: Between these two types of the shank, 6 flat shank is compatible with manual portable drills and pillar drilling tools. Conversely, a step drill with a hex shank is suitable for an automatic drilling tool, and it doesn’t require screwing.

The usage of a Step Drill Bit

The step drill bit is used for a wide range of applications while a typical drill bit only drills holes. a few common applications for a step drill bit are as follows:

Drilling Sheet Metals: The step drill bit is frequently used to make a hole in 1/4′′ or thin sheet metal. While a typical twist bit can create a mess on thinner sheet metal, the step drill bit is reliable for handling such rigid material. This drill bit slowly shaves off the tough metal and offers a larger hole progressively leaving a nice beveled edge.

Drilling Carbon Fiber: Carbon fiber requires extra care to create a hole through it. thus most DIY enthusiasts use a step drill bit as it can drill through this sensitive material without damage.

Drilling Plastics: The step drill bit is also the first choice for many experienced DIYers for drilling holes into plastic. Using the drill bit offers a smooth hole in the plastic without damaging it. Apart from plastics, step drill bits are suitable for drilling through soft material as well.

Enlarge Holes: Because of the shape, the step bit is great for enlarging the existing holes efficiently. In most cases, enlarging an existing hole is problematic. But the step-by-step tip design makes the step drill bit a superb option for handling such difficult tasks.

Deburring Holes: After drilling holes through the workpiece, typically the drill bit leaves sharp edges which can hurt the user. Though a rat tile file is handy for deburring, a step drill bit can also does the same job. Only you have to use the next step edge of the bit for deburring.

Creates Knock out Holes: You can create knockout holes using the step drill bit if there isn’t a knockout punch. Doing so also prevents the metal particles from flying around, which is a great advantage of using a step drill bit.

Benefits of Step Drill Bit 

Convenient to use: A step drill bit carries plenty of diameters, making it suitable for creating various sized holes using a single bit. It may need a two step bits for creating a variety of sizes of holes, but the DIYers wont require several drill bits likewise a twist drill bit. Despite this, the step drill bit is compatible with lots of surfaces including metals, wood, and plastic.

Creates smooth holes: Along with CBN-ground sharp cutting edges, this drill bit offers a straight hole with a smooth edge. Once done, you will have a burr-free hole with a chamfered edge.

Faster drilling operation: Since the step bit doesn’t require a pilot hole and its spiral fluted design ensures smooth cutting without grabbing, this drill bit can dig into the surface quickly. During drilling, the step drill bit removes the chips efficiently which also ensures faster operation.

Multifunctional drill bit: Whether you need to create a hole or enlarge the existing one, the step drill bit will be handy for both purposes. Apart from these, this drill bit can chamfer the hole surface conveniently.

How to Use Step Drill Bits

Every step of this drill bit is larger than the previous one and it’s a self-starting drill bit. To use a larger step bit, you will require a pre-drilled hole with the same diameter as the smallest step of the larger step bit. So, using a step drill bit requires a unique procedure. The following is the right process for using the step drill bit:

Place the drill bit accurately

Firstly, wear your protective gear to be prepared for the task. Since the step bit doesn’t require a pilot hole, placing the bit point in the exact place is vital. To make the task efficient, create a center mark on the exact point of the working surface with a hammer and center punch. It will let you identify the exact spot and place the drill bit accordingly.

Attach the drill bit

Insert the step drill bit into the drill chuck and secure it properly. Before powering on the drill, you can apply cutting fluid on the work surface to make the drilling task even more convenient.

Start drilling

Place the smaller-sized step bit tip on the center mark of the working surface. Press the power trigger to run the drill. Drill the workpiece completely and periodically apply cutting fluid to lower the temperature that may be created due to the friction.

Replace the drill bit

If you have done so, release the power drill’s chuck and replace the drill bit with a larger size. Then secure the drill bit on the drill and insert this larger bit tip into the pre-drilled hole. Before drilling once again, apply some cutting fluid to the larger bit and around the edge of the hole.

Continue drilling

Switch on the power drill and start drilling the hole using the larger bit. Make sure you aren’t drilling consistently if the workpiece is metal, as doing so can cause excessive heat and ruin the project. So to keep the operation under control, frequently stop drilling and apply cut fluid. Repeat the method until you reach the desired depth.

 Clean the Equipment

After drilling to the desired depth, power off the drill and remove the bit from the chuck. Remove metal chips from both step drill bits using a rag. Also, remove the metal chips from the workpiece. Finally, store the drill and accessories in the toolbox to prevent damage and rust.

Some helpful tips for using Step Drill Bit

While using the step drill bit to create a hole in a soft or hard surface, keep these tricks in mind to make the task safer and more precise:

  • Keep the drill bit straight against the working surface as a tilted position can cause oblong holes.
  • Don’t apply excessive pressure and let the drill bit do the most of the task.
  • Drill slowly so you don’t miss the required step to get the desired diameter hole.
  • If it is an HSS step drill bit, apply low to gentle spindle speeds, otherwise, it can cause chatter.
  • Though the step drill bit doesn’t require a pilot hole, you should use it, especially for creating a larger diameter hole.
  • Periodically apply the cut fluid to keep the step drill bit cool, especially while dealing with sheet metal.
  • Pull out the step drill bit frequently to prevent overheating.

FAQs on What is a Step Drill Bit

How to sharpen a step drill bit?

If the step drill bit gets slightly dull, use a coarse diamond hand lap to sharpen it. But if the drill bit gets completely dull, you will have to use a bench grinder to restore its productivity.

Can I use a step drill bit to drill through the wood?

A step drill bit is mostly suitable for creating holes in metal that isn’t thicker than 1/4 inch, but it will work on wood. But most of the wooden applications require deeper holes with smaller diameters. So, maintaining such dependability can be difficult for a step drill bit.

When to use a step drill bit?

If you require a precise hole in tough material like a sheet, you can use a step drill bit. In particular, this drill bit can offer different diameter holes using a single bit. Despite it doesn’t require a pilot hole, it is suitable for faster and accurate drilling on hard surfaces.

Final words

The step drill bit is a deal-breaker for busy DIYers who often need to deal with the metal surface for various size holes. As the step bit can greatly enlarge the existing hole, it is a convenient solution for professional enthusiasts for repairing home improvement tasks.

Once you have understood what is a step drill bit, enjoying its advantages will be easier for you. Learning about this specific type of drill bit improves the skill and ability of professional DIYers, but it is not completely user-friendly for seasonal and novice DIYers.

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Sam Morgan is a professional interior designer and part time content writer of Machine Handyman. He is a lifelong tools enthusiast and loves accessories of all shapes and sizes! He always research on different types of improvement tools like drill, air compressor, saw, nail gun, screw gun, grinder, cutting tools etc. Sam works hard on his project and try to find out which machine or tool will get him perfect results.

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