- Published 17 Jan 2023
- Last Modified 29 Aug 2023
- 5 min
Screw Extractors - A Complete Guide
Our screw extractors guide will help you understand how they work, how to use them, and common sizes.
What are Screw Extractors?
A screw extractor is a specialist tool used to remove broken or damaged screws from a piece of work without damaging the thread. They are like screws in appearance but have a reverse thread. These tools are designed for use with both manual and powered hand tools such as adjustable spanners, drills, and vice grip pliers.
They may also be known as bolt extractors or tap extractors.
How Do Screw Extractors Work?
Using a screw extractor is simple. First, you will need to drill a pilot hole in the broken screw or bolt. You must then thread in the opposite hand thread extractor. Once the extractor is at full depth of the thread, it can be used as an extension of the screw or bolt. This then allows it to be easily removed from the workpiece.
These tools are typically made from durable metals such as HSS, alloy steel, carbon steel, and hardened chrome vanadium steel. Coupled with their spiral flutes design, this robust construction means that they are suitable for removing many types of screws, studs, bolts, and fasteners. Various sizes are available for use with different sizes of fastener and most screw extractors can be used with fixings of medium tensile strength.
Why Should You Use a Screw Extractor?
There are several benefits to using a screw remover kit.
The most straightforward reason to use these tools is their convenience in the event of stripped, rusted, or broken bolts. Damaged screws should be replaced, and extractors are designed to provide a quick and easy solution to this problem.
Using an extractor allows you the advantage of not having to make a bigger hole in the workpiece. This means that it can retain the same size screw in the existing hole, making for a neater, cleaner finish once the problematic screw has been successfully removed.
One of the main reasons to use a bolt extractor is if the integrity of the pre-existing thread needs to be kept intact in the workpiece. This is often the case because it then allows you to replace the bolt with the same thread size. This prevents the need to drill the hole and subsequently repair it to the original thread size.
How to Use a Screw Extractor
Follow these steps to learn how to use a screw extractor safely and effectively:
- Choose a drill bit that is smaller in size than the screw that needs removing. For assistance with this, please see our size chart further on in this guide
- Attach the drill bit and line it up with the screw head
- Carefully drill a pilot hole in the centre of the existing damaged screw
- Insert the spiral end of the extractor into the newly drilled hole
- Screw the extractor into the pilot hole. You should always use the opposite hand thread, meaning that it should be twisted counterclockwise
- Twist the extractor anti-clockwise until it has reached its full depth
- Grip the protruding end of the extractor with a wrench and twist it until the screw loosens
- If you are using a power tool for added gripping power, attach the drill to the protruding end of the extractor and power the drill with a reverse rotation
- Once the troublesome screw has been loosened, you should then be able to easily extract it with a pair of pliers
This process should unscrew the stubborn screw from its hole.
Handy How-to Guide
Do you want to see how to use a screw extractor kit first-hand? Our helpful video shows you the basics of using these tools, covering all the essentials you need to know.
Interested in learning more? Click to watch our video or browse via the button below to shop our full range of RS Pro screw extractor kits.
How to Remove a Screw with No Head
If the screw you want to remove has no head, this will present more of a problem. In this scenario, it may be easiest to use a drill with a bit that is the same diameter as the screw to simply drill it out.
How to Remove a Small Stripped Screw
To remove a small stripped screw, you will simply need to follow the same process as you would for removing a standard-sized screw with a stripped head. The only difference is that you will just need to use a smaller screw extractor set.
Screw Extractor Sizes
The sizes for screw extractors are directly derived from the corresponding screw and bolt sizes. Therefore, making sure that the extractor size is right for the specific type and size of the screw is essential. Most screw removers are available in kits featuring multiple tools of various sizes for convenience and ease of use. This is ideal for professionals and those regularly requiring removers suitable for different sizes.
You should also be aware that different manufacturers may use their own extractor sizes. However, if this is the case, these should always be provided with a screw size reference chart.
This table should help you determine the right extractor size for your application:
Size of Screw or Bolt to be Removed | Pre-Drill Size | Extractor Size |
|---|---|---|
5-8mm | 3.5mm | Number 1 |
10mm | 5mm | Number 2 |
10mm | 6mm | Number 3 |
12-14mm | 8mm | Number 4 |
16mm | 9.5mm | Number 5 |
20mm | 12mm | Number 6 |
Why Choose RS?
So, now you know how to use an extractor and how to determine the right size for your application, all that's left to do is to browse and shop for screw extractors. We offer a range of tools and kits, but why should you consider buying from RS?
- Over 500,000 top-quality products from more than 2,500 leading brands and manufacturer
- All the information you need, when you need it, from technical datasheets to specific product details
- A wide range of delivery options (including next-day and same-day delivery) to suit your project requirements