How to Enlarge an Existing Hole in Metal?

If you have a hole in metal that needs to be enlarged, don’t worry – there is a way to do it!

A tool called a reamer is used to widen holes or realign mismatched ones in metal.

A reamer can simply increase the size of existing holes, not create them from scratch [1].

In this blog post, we will discuss three methods that you can use to enlarge an existing hole in metal. Each method has its own set of pros and cons, so make sure to read through all of them before deciding which one is right for you.

Can You Enlarge a Hole in Metal?

The fact is that if you can drill into metal and cut it apart, there’s no reason why you couldn’t expand an existing hole.

When a hole is reamed in metal, it elongates the space and creates a precise one. Reaming is the process of making holes larger.

Reaming is a necessary operation to increase the hole in your metal device so that you don’t have to change your approach. It will allow you to make a round hole with the correct diameter.

It’s the last step in finishing up an existing hole with extreme precision. This is instructive content on how to increase the size of a hole in metal [2].

Increasing a current hole in metal is more difficult than expanding one in wood, primarily because metal is far more durable than wood. However, there are still a number of excellent procedures for doing this job.

Ways to Enlarge an Existing Hole in Metal [3]

Metal File

If you need to make a large hole, start with a small hole and use a metal file to enlarge it:

• Start by using a round file to create an indent in the center of the existing hole;
• Work the file around the circumference of the hole, angling it inward as you go;
• Use back-and-forth strokes until the file has cut through enough metal to create your new, larger hole;

You can also use a rat-tail file for this purpose. A rat-tail file is thinner and narrower than a round file, so it can maneuver more easily in tight spaces.  It’s also useful for enlarging holes that are located in hard-to-reach places.

A half-round file has a rounded tip and a flat side. Use the flat side of the file to widen the hole by working it back and forth. Angle the file so that it’s parallel to the metal surface for best results.

You can also use a three-square file, which is similar to a half-round file but has three flat sides instead of one.

Specialized Sandpaper

You may use an abrasive tool such as a grinding wheel or sandpaper to smooth out the edges of the enlarged hole:

• First, use course-grit sandpaper to remove any burrs or sharp edges;
• Wrap the sandpaper around a cylindrical object like a dowel rod or pencil and insert it into the hole;
• Twist the paper as you pull it out to enlarge the hole slightly;
• Repeat this process until the hole is as large as you need it to be;
• Then, use finer-grit sandpaper to smooth out the surface of the metal around the hole;
• Wipe away any dust with a clean cloth before moving on;

Tapered Reamer

If you need to enlarge a hole with smooth, clean edges, use a tapered reamer. A tapered reamer is a hand tool that looks like a drill bit with spiral flutes. It’s used to enlarge existing holes or create new ones.

To use a tapered reamer, insert it into the hole and turn it clockwise:

• The flutes will cut through the metal and widen the hole as you turn;
• Be sure to lubricate the reamer with cutting oil before using it on metal;
• This will help prevent the tool from overheating and damaging the metal surface;
• Stop enlarging the hole when it reaches the desired size;
• Remove any burrs with a file or sandpaper before moving on;

Jab Saw

A jab saw is another tool you can use to enlarge a hole in metal. It’s a hand saw with a thin, sharp blade that’s designed for cutting through metal. 

To use a jab saw, insert the blade into the hole and start sawing back and forth:

• Angle the blade so that it’s parallel to the metal surface;
• Use steady, even strokes to avoid damaging the metal;
• Work slowly and carefully until the hole is as large as you need it to be;

Hole Saw

A hole saw is a powerful tool that’s designed for cutting round holes in metal. It consists of a metal cylinder with sharp teeth on the edge.

To use a hole saw you should do the following things:

• First, drill a pilot hole in the center of the area you want to cut;
• Then, attach the hole saw to your drill and insert it into the pilot hole;
• Start the drill and let it do its work;
• The hole saw will cut through the metal and create a perfect circle;
• Stop drilling when the hole is as large as you need it to be;
• Remove any burrs with a file or sandpaper before moving on;

Power Drill

You can also use a power drill with a metal-cutting drill bit to enlarge an existing hole in metal:

• First, make sure that the drill bit is properly lubricated with cutting oil;
• Then, insert the bit into the hole and start drilling;
• Use steady, even strokes, and stop when the hole is as large as you need it to be;
• Remove any burrs with a file or sandpaper before moving on;

Mistakes to Avoid, Tips & Tricks [4]:

• The dust created by metal shavings is extremely harmful, therefore always use the proper eye protection;
• Metal shavings and burrs can be very sharp, so when drilling and working with metal, we recommend wearing some massive word gloves;
• If the metal is too thick, you might not be able to enlarge the hole with a simple drill bit. In that case, you will need to use a hole saw;
• Last but not least – don’t forget to clean up when you’re done! Metal shavings and dust can be very difficult to remove, so it’s best to do it while they’re still fresh;

While the hand techniques we covered today are effective, they need a lot of work because, as you well know, metal is extremely hard. As a result, any of the alternatives we discussed that utilize power tools are most likely the best methods to pursue.

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FAQ

How do you enlarge an existing hole in a metal object?

If the hole is small, you can try using a hand file or a rotary tool with a grinding bit. For larger holes, you’ll need an electric drill with a metal-cutting bit. Start by drilling a series of smaller holes around the edge of the existing hole, then use a file or grinder to enlarge it to the desired size.

Another option is to weld a metal ring or plate over the hole, then grind it down to the desired size. This method works best if the surrounding area is flat and smooth.

How can you make a hole in metal bigger without a drill?

There are a variety of alternatives for creating a bigger hole without the use of a drill.

A mandrel (the right diameter) and sandpaper, a hand file, or a jab saw can all be used to make an opening larger.

It’s also advisable to first draw the required diameter and then manually file away the extra wood until the hole is the correct size [5].

How do you enlarge a deadbolt hole?

Use a hole saw that is the same size as the new deadbolt. If your old deadbolt was smaller than the new one, you will need to enlarge the hole with a spade bit or other tool. It’s best to do this before installing the new deadbolt so that you can get an accurate measurement.

If you are unsure about what size hole to make, it is always better to make it too big rather than too small. You can always use a filler such as wood putty or caulk to fill in any excess space around the new deadbolt.

What type of file is used for enlarging holes?

Rotary files are available with a rotary shank. They run on a custom-built machine with a portable motor and flexible shaft. These are utilized for hole expanding and mold creation [6].

Different types of files are used for enlarging holes, depending on the size and shape of the hole.

For small holes, a hand file or a rotary tool with a grinding bit can be used.

For larger holes, an electric drill with a metal-cutting bit is necessary.

What tools are used to process the process of enlarging a hole that has already been drilled?

3 main tools that are used to enlarge an existing hole in metal are drilling, reaming, and boring:

• Drilling is the process of making a hole with a rotating drill bit;
• Reaming is the process of enlarging a previously drilled hole with a reamer;
• Boring is the process of enlarging a hole that has already been drilled or cast with a boring bar;

How do you ream a hole in metal?

Reaming is usually done with a rotary cutting tool, such as a drill bit or end mill. The cutting edges of the tool are ground to a smooth, slightly tapered point. This tapered point helps to guide the tool as it cuts through the metal and produces a smooth, clean hole.

Reaming can be performed by hand, but it is more commonly done with a machine such as a lathe or milling machine. The speed at which the tool is rotated and the feed rate (how quickly it moves through the metal) are both important factors in achieving a good result. If the tool is rotated too slowly, it will produce a rough, uneven hole. If the feed rate is too fast, the tool may break or damage the workpiece.

Reaming is most commonly used to enlarge an existing hole that has been drilled or machined. It can also be used to create a new hole of a specific size and shape. When reaming, it is important to use a cutting lubricant such as oil or coolant to prevent the tool from overheating and damaging the workpiece.

How do you properly file metal?

You may properly file brass, bronze, copper, and tin with a double-cut file. These hard metals should be filed using a double-cut file since they are strong enough to resist both the metal and/or alloy.

Wood can also be cut with rasp-cut files made of lead and aluminum. This file has a series of distinct teeth that produces a rough cut [7].

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Useful Video: How to enlarge an existing hole saw hole

References:

1. https://holemaker-technology.com/blogs/news/how-to-enlarge-a-hole-or-align-a-hole-in-metal
2. https://toolsprokit.com/how-to-enlarge-an-existing-hole-in-metal
3. https://handymansworld.net/how-to-enlarge-holes-in-metal
4. https://toolsprokit.com/how-to-enlarge-an-existing-hole-in-metal
5. https://www.lathamshardware.co.uk/blog/how-to-guides/ultimate-guide-to-making-holes-without-a-drill
6. https://testbook.com/question-answer/the-file-used-by-die-makers-for-enlarging-the-hole–5f279a8d62f6530d0aedca43
7. https://www.wikihow.com/File-Metal