Sheet metal is a common material used in many different industries.
This lightweight material is easily stored and easily transported. It is weather resistant and extremely durable. Sheet metal is used in industries such as automotive, aerospace and construction. Common sheet metal includes aluminum, zinc and stainless steel sheets.
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What is sheet metal fabrication?
Sheet metal fabrication refers to the whole process of shaping metal sheets to a specific design using a number of different manufacturing methods. The process usually involves steps such as cutting, forming and joining.
While many techniques, tools and equipment are available and can be used to achieve a good end result, different methods have different costs. Thus, choosing the right method and tools for your needs is vital in order to optimize the manufacturing process.
Tools used for cutting sheet metal
Sheet metal fabrication requires special tools for the cutting, forming and joining processes.
The cutting process includes the following tools:
- Chop saws are motorized power tools that can cut precise square and angled cuts. It has a circular steel saw blade that spins at high speed. The blade cuts through the material that you are working on when the handle is pushed downwards. Chop saws are also known as miter saws.
- Band saws have a long, sharp blade in which a continuous band of toothed metal is held between a minimum of two wheels. They can cut irregular and curved shapes. Band saws are a versatile tool that can cut a number of materials including metal and wood.
- Cutting torches are similar to welding torches but have an oxygen blast trigger. The cutting torch heats the metal until a certain temperature is reached. Once the temperature is reached, oxygen is released and reacts with the metal to produce more heat for the cutting process.
The forming processes utilize tools and equipment such as:
- Oxy-acetylene torches are gas torches that produce a high temperature flame by mixing acetylene and oxygen. They are used to cut, weld as well as straighten warped steel. Heat is applied to the metal in a linear direction slowly to remove significant warpage.
- Hydraulic brakes are a braking system mechanism that uses brake fluid to transfer pressure from the controls to the brakes.
- Rolling machines are used to roll metal sheets into round or conical shapes. They are also sometimes referred to as roll bending machines or plate bending machines.
The joining process usually involves:
- Welding equipment and techniques. There are numerous welding techniques that can be used when it comes to sheet metal fabrication. These techniques include special straightening processes, using a stout fixture or staggered welding.
- Rivet gun is a tool that is utilized to drive rivets. Rivet guns are usually pneumatically powered. They are also known as rivet hammers or pneumatic hammers.
- Brazing equipment is used to join two metals together. This is achieved by melting a filler metal between the two metals without actually melting the metals that are to be joined. Brazed joints are strong and have a clean, finished appearance.
How to cut sheet metal without power tools?
Power tools can cost a lot but if you do not have the budget for it, here are a number of hand tools you can use to cut sheet metal.
Tin Snips are very affordable. They look and work like scissors, but have extremely sharp jaws that can pierce sheet metal. Tin snips are easy to use and are able to give accurate cuts. Left and right cutting tin snips allow you to cut curves.
Chisels can be used to cut precise shapes. You can use a cold chisel or a hot chisel that needs to be heated up before you use it. Chisels can also be used to remove extra metal.
Hacksaws are common tools that you can easily find at a hardware store. It is easy to use and very effective in cutting sheet metal. Hacksaws are especially good for cutting steep angles. Do choose the correct blade for the material that you are cutting to avoid any damage and be careful to smooth down the jagged edges after cutting.
Straight cutters were designed to make straight cuts and gentle curved cuts. Depending on your projects, you can get models that are able to cut right, lefts or circles.
Bench shears are purposed for cutting a higher quantity of metal. It is called a bench shear because this tool is mounted on the bench. It is a precise tool that can cut through thick sheet metal smoothly.
Utility knife is one of the quicker tools that can cut metal. If you have the experience you can even use it to cut straight lines. Contractors use it to make customized cuts when they do not have power tools at hand. Do be careful as the blade can slip and cause injuries. If you are using a utility knife, make sure you are wearing gloves.
Some FAQs on sheet metal cutting
How to cut a round hole in sheet metal?
If you do not have power tools, you can use a hole punch plier to cut a round hole in sheet metal. Hole punch pliers have a pin attached to the end of the pliers. When you press the pliers together with force, the pin will punch a clean hole through the sheet metal.
You can also use a drill to cut the hole. The first step in using a drill is to locate the center of the hole and outline the hole using a compass. Next, use a center punch on the center of the hole to create dimples on the metal sheet.
Once this is completed, make sure that you clamp your metal sheet down so that it does not spin when you start drilling. Holding it with your bare hands is dangerous.
Before you start drilling, choose the drill that you want to use. This depends on factors such as hole size, how quickly you want to get the job done as well as how much force you need to apply.
Twist drills are good for small holes. Step drill bits can help you create holes of different sizes, but can only be used on thin sheets of metal.
Once you have cut the hole, you will have to use a deburring tool to smoothen the edges of the hole. Hole burrs depend on the drill or cutter that was used.
How to cut sheet metal roofing?
The roof is one an important part of any construction project and it’s best to ensure the highest quality work when installing a new roof.
- Tools to cut sheet metal (tin snips, a nibbler or electric shears, circular saw)
- Measuring tape
- Combination square
- Metal roof panels
- A Marker
Step 1: Preparation
Preparation is key when it comes to avoiding mistakes. You will need to start by placing the metal roofing on your workbench. The proper side should be facing up and the sheets should be fixed firmly as to prevent it from moving when being cut. You can use adjustable clamps to hold the metal in place.
Determine the size, shape and number of panels that you will need, based on the measurements of your roof. Measure and mark the sizes that you will have to cut. Take your time doing this as it will help you to have cuts that are straight. Be as precise as possible as even small mistakes will cause damage to the metal sheet.
Once you are ready, put on the appropriate safety gear, such as protective gloves and goggles.
Step 2: Cutting the metal
There are different tools that you can use to cut metal panels.
Tin snips are best suited for short cuts on soft metals. You should be aware that there are different types of tin snips. Use the ones that are most appropriate for the cuts that you want to make on the metal.
As the way tin snips work are very similar to a regular scissor, it is an easy and cheap tool to use. However, it is also slow and very troublesome for large sheets of metal.
A nibbler is a tool that cuts around corners easily. It is perfect for straight, clean cuts as well as speciality cuts. It can also be attached to a circular saw. This is one of the best tools for cutting sheet metal roofing.
There are two types of electric shears.
Single cutting shears work like normal scissors but have blades that are powered. This enables better cuts, but may cause bends on the metal sheets that are being cut. Thus, if you need straight cuts for your roof, single cutting shears might not be the right tool choice.
Double cutting shears have two cutters. They cut with less distortion, but are not appropriate for curves or heavy metals.
Electric shears are easy to use. All you have to do is hold them down and press the trigger. You will be able to control the movement of the shears according to the cutting line. These shears can cut metal sheets quickly.
One of the drawbacks of electric shears is that they may get stuck in the middle of a cut. If this occurs, it’s best that you start for the opposite side of the same cut. Forcing the tool will most likely damage the metal.
Circular saws work well when cutting through multiple sheets of metal. However, if you do not have the experience, then it is best that you do one sheet at a time till you get the hang of it.
It is important that the exposed side of the tin faces downwards when you are using a circular saw to cut through the metal. This ensures that there are no damages to the sheet. Approach the cut from a right angle. Precision is key, so take your time making the cut. You only have one chance to make a clean, accurate cut. Use minimal pressure when using a circular saw.
Remember to clean up the metal dust that accumulates during cutting. Leaving it on the metal sheets when installing your roof will cause your roof to weaken and damage quicker because the dust rusts easily.
How to cut sheet metal straight?
All you need to make a straight precise cut on sheet metal is a pair of tin snips and a pair of work gloves to avoid injury. The problem with cutting sheet metal is that it is a tough material that has sharp edges. The sheet metal itself gets in the way the farther you are into the cut. This makes it difficult to cut sheet metal straight. However, here are some things that you can do to keep your cut as straight as possible.
- Mark out your cutting line so that you can make precise cuts according to the line.
- Before making the cut, open the jaws of the tin snips as wide as possible. This is because the cutting force at the back for the jaws is far greater than the front. Align them to the cutting line and make your cut.
- When you are making a cut, do not close the jaws of the tin snips all the way. Doing so will bend the metal at the end of the cut. Stop cutting when you reach the tips and open the jaws of the tin snips all the way again for the next cut.
- Take your time and don’t rush the cut.
How to cut intricate designs in sheet metal?
Sometimes you will need or want to cut an intricate design on your sheet metal. This will require some detailed work and/or interior cuts.
If you are doing this without power tools, you can start the process with a set of hole punch pliers. This tool is suitable only for thin sheet metal. If you are using thicker sheet metal, you will need to use a drill.
First, pierce the sheet metal with the hole punch pliers. Then take a saw blade and put it through the hole created by the punch pliers. Once you have done this, fix the saw blade back into its frame and secure it. You can now start sawing the pattern that you want.
How to cut sheet metal with a Dremel?
A Dremel is not really a tool but instead a company that manufactures rotary tools. Rotary tools can be used for cutting, polishing, sharpening, sanding among others. You can use it to cut sheet metal, but do check which attachments that are required for the material that you intend to cut. Always make sure that you wear safety equipment when you are using a Dremel.
Step 1: Attach the cutting wheel to the Dremel. Check that the blade is sharp so that the cut that you make has a smooth finish
Step 2: Once the Dremel is ready, measure and mark the metal workpiece. You can do this with a pencil or a marker.
Step 3: You need to make sure that the metal is held firmly and does not move when you start cutting. You can use a bench vise or a clamp.
Step 4: Now you can start cutting. Align the cutting line and the cutting wheel. Ensure that the blade is in the right position so that your metal sheet is not damaged.
Step 5: Turn on the Dremel and the cutting wheel will start rotating. Wait till it reaches top speed before you start the cut. Hold the tool with two hands for a more controlled cut. Take your time as putting too much pressure might result in damage to the metal.
Tips to keep safe when cutting sheet metal
A safe work environment will help prevent unwanted accidents from happening. Here are a few things you can do to keep safe when working with sheet metal.
- Wear gloves for protection. While you will get a better feel for metalcraft without gloves, do put them on until you are more familiar with the tools and materials.
- Do not grasp metal pieces tightly. This will help you to avoid cuts.
- Do not run your fingers along raw edges.
- Wear safety glasses to protect your eyes
- Wear a dust mask to prevent sheet metal dust from being inhaled.
- When cleaning up, do not brush metal scrapes into the trash with your hands. Use a brush or cardboard to push them along.
- Do not attempt to carry oversized pieces of sheet metal on your own.
- Invest in good tools and ensure that your tools are working properly before using them.
- Make sure your workplace has adequate
- Take your time on your project. Rushing yourself will only result in injuries.
Sheet metal is a versatile material that can be used in many ways. It is used in major industries as well as by those who are doing home D.I.Y. projects. One of the best things about working with sheet metal is that you do not need a big budget for tools.
It can be cut with power tools as well as hand tools. Always remember to wear protective gear when you are cutting sheet metal to avoid injuries as there are sharp edges and corners