How thick is a metal sheet? The answer depends on two main things: its gauge number and the metal type. Sheet metal thickness is often referred to as “gauge.” This system might sound strange at first. A high gauge number indicates the metal is thinner.
The thickness of sheet metal can vary. The thin side starts at about 0.006 inches (0.15 mm). The thick side is around 0.25 inches (6.35 mm). Knowing this range is your first step.
The main difficulty is that gauge differs for different metals. For instance, 16-gauge steel is not the same thickness as 16-gauge aluminum. This difference is not negligible. If you forget about it, it can lead to expensive mistakes. As custom metal part pros at Mekalite, we know that understanding materials is half the battle.
This guide will teach you everything about sheet metal thickness. We will talk about the gauge system. We will provide you with conversion charts. We will help you choose the thickness needed for any task. You will go from being uncertain to being sure.
What is Sheet Metal Gauge?
The gauge system can be confusing. However, it is a must for anyone working with metal. Understanding the ‘why’ behind it is crucial for avoiding mistakes. Knowing how thick is sheet metal is about more than just a number.
The Golden Rule of Gauge
The most important and simplest rule is: higher gauge numbers mean thinner metal. A 22-gauge sheet is thinner and more flexible than a 14-gauge sheet.
Think of it like sandpaper. A high grit number, like 220-grit, is very fine. A low grit number, like 80-grit, is coarse. The same logic applies to sheet metal gauge. A higher number means a “finer” or thinner sheet.
Why Gauge Isn’t Universal
Gauge systems were created based on weight, measuring the weight of a metal sheet per square foot. This is why thickness changes for each gauge number depending on the material.
The explanation is straightforward:
- Different metals have different densities. Steel is much denser and heavier than aluminum.
- A one-square-foot sheet of steel will be thicker or thinner than aluminum that weighs the same.
- This is why you must always use a chart made for your specific metal.
While gauge is common for talking about thickness, professionals rely on exact measurements. For precision work, the actual thickness affects the fabrication process performance. Engineers and fabricators always use precise thickness in inches or millimeters for accurate results.
The Thick and the Thin: Absolute Thickness Charts
These charts are the most valuable tool for figuring out sheet metal thickness. They give you direct data to convert gauge to actual thickness for common metals.
How to Read the Chart
Using the chart is simple. This two-step process will help you quickly find out how thick sheet metal is.
- Find your material’s gauge number in the first column.
- Move across that row to find the matching thickness in inches or millimeters for your metal type (Steel, Stainless, or Aluminum).
Master Conversion Chart
This table gives you quick reference for converting gauge to inches and millimeters. We have highlighted the most common gauges to make them easy to find.
| Gauge | Standard Steel (in / mm) | Stainless Steel (in / mm) | Aluminum (AWG) (in / mm) |
|---|---|---|---|
| 7 | 0.1793″ / 4.55mm | 0.1875″ / 4.76mm | 0.1443″ / 3.67mm |
| 8 | 0.1644″ / 4.18mm | 0.1719″ / 4.37mm | 0.1285″ / 3.26mm |
| 9 | 0.1495″ / 3.80mm | 0.1563″ / 3.97mm | 0.1144″ / 2.91mm |
| 10 | 0.1345″ / 3.42mm | 0.1406″ / 3.57mm | 0.1019″ / 2.59mm |
| 11 | 0.1196″ / 3.04mm | 0.1250″ / 3.18mm | 0.0907″ / 2.30mm |
| 12 | 0.1046″ / 2.66mm | 0.1094″ / 2.78mm | 0.0808″ / 2.05mm |
| 13 | 0.0897″ / 2.28mm | 0.0938″ / 2.38mm | 0.0720″ / 1.83mm |
| 14 | 0.0747″ / 1.90mm | 0.0781″ / 1.98mm | 0.0641″ / 1.63mm |
| 15 | 0.0673″ / 1.71mm | 0.0703″ / 1.79mm | 0.0571″ / 1.45mm |
| 16 | 0.0598″ / 1.52mm | 0.0625″ / 1.59mm | 0.0508″ / 1.29mm |
| 18 | 0.0478″ / 1.21mm | 0.0500″ / 1.27mm | 0.0403″ / 1.02mm |
| 20 | 0.0359″ / 0.91mm | 0.0375″ / 0.95mm | 0.0320″ / 0.81mm |
| 22 | 0.0299″ / 0.76mm | 0.0313″ / 0.80mm | 0.0253″ / 0.64mm |
| 24 | 0.0239″ / 0.61mm | 0.0250″ / 0.64mm | 0.0201″ / 0.51mm |
| 26 | 0.0179″ / 0.45mm | 0.0188″ / 0.48mm | 0.0159″ / 0.40mm |
| 28 | 0.0149″ / 0.38mm | 0.0156″ / 0.40mm | 0.0126″ / 0.32mm |
Picking the Right Thickness
Knowing the numbers is one thing, but applying them is what matters. This guide helps you connect gauge numbers to real projects and choose the right material every time. This is key to understanding how thick sheet metal should be for your needs.
From our shop experience, matching thickness to the job is the most important decision. Selecting the correct thickness is critical for any successful производство листового металла project. A wrong choice can lead to parts that are too weak, too heavy, or too expensive.
High Gauges: 7 to 12 Gauge
This range is all about strength and toughness. These sheets are heavy and rigid. They can handle major stress and weight.
- Features: High strength, excellent rigidity, and great for load-bearing jobs. This material is hard to bend and needs powerful machinery.
- Common Uses: Structural supports for buildings, heavy-duty mounting brackets, frames for industrial equipment, and thick base plates for machinery.
Medium gauges: 13 to 18 Gauge
This is the versatile workhorse of sheet metal. It offers a great balance of strength, formability, and manageable weight. It’s the most common range for many products.
- Features: Good strength-to-weight ratio, can be formed and bent with standard shop equipment, and is tough enough for demanding uses. Figuring out how thick is sheet metal in this range is a common task.
- Common Uses: Car body panels, doors, and fenders. Also used for electrical boxes, server racks, trailer siding, and tough equipment frames.
Light Gauges: 19 to 26+ Gauge
When your project needs to be lightweight, easy to shape, or cost-effective, thin gauges work well. This material is highly formable and perfect when strength is not the main concern.
- Features: Very easy to bend and shape, lightweight, and lower in cost. Not suitable for structural or high-stress jobs.
- Common Uses: Cases for computers and electronics, HVAC ductwork, small electronic housings, decorative panels, custom signage, and metal roofing.
Beyond the Basics
To truly master sheet metal, you need to understand a few more advanced topics. These details separate beginners from experts. They ensure your projects are precise and successful.
Sheet vs. Plate vs. Foil
The words “sheet,” “plate,” and “foil” are not the same. They describe different thickness categories. While standards can vary slightly, the general definitions are clear.
According to industry sources, the typical thickness of sheet metal is between 0.5 millimetres and 6 millimetres. Anything thinner is foil. Anything thicker is plate.
For steel, this change is often defined by gauge. Material changes to what the industry calls plate metal after crossing over 7GA (about 0.18 inches or 4.6 mm). Plate is used for heavy-duty structural jobs like building bridges or ship hulls. Foil, like household aluminum foil, is extremely thin. It’s used for packaging and insulation.
Tolerance: The Small Measurement
Tolerance is the small, acceptable amount of variation in material thickness. No manufacturing process is perfect. So a sheet specified as 1.5 mm thick might actually be 1.52 mm or 1.48 mm.
This is written as a plus-or-minus value, such as +/- 0.005 inches. For projects where parts must fit together perfectly, understanding tolerance is crucial. This includes aerospace or high-end electronics.
The Influence of Thickness on Fabrication
The thickness of your sheet metal directly affects how you can work with it. This is critical for any project.
- Сгибание: Thicker metal is harder to bend. It needs more force and a larger inside bend radius. If you try to bend thick metal too sharply, it can crack or break.
- Welding: Thicker materials often need special preparation, like beveled edges, to ensure a strong weld. They also need more heat. Thin materials are very sensitive to heat and can easily warp or burn through if not welded carefully.
- Стоимость: The connection between sheet metal thickness and cost is simple. Thicker material weighs more. Since metal is sold by weight, it costs more. Thicker material can also increase labor costs due to slower processing times.
How to Measure Thickness
Checking the thickness of your material is good practice. There are two common tools for the job. Each has its own benefits. Knowing how to measure helps you confirm you have the right material.
Using Digital Calipers
This is the most precise method for measuring sheet metal thickness. Digital calipers give you an exact reading in inches or millimeters.
- Start by making sure the caliper jaws are clean. Close them and press the “zero” button to calibrate the tool.
- Gently clamp the jaws onto a flat part of the sheet. Measure away from any bent edges or rough-cut burrs. These can give a false reading.
- Read the exact measurement on the digital screen. Take measurements in a few different spots to check for consistency.
Using a Thickness Gauge
A sheet metal thickness gauge is a fast and simple tool for quick checks. It is a flat piece of metal with labeled slots of different widths.
- Take the tool and find the slot that your sheet metal fits into perfectly. It should feel snug but not forced.
- Read the gauge number stamped next to that slot. This will tell you the gauge of the material. This tool is great for identifying unknown material in the shop but is less precise than calipers.
Conclusion: Equipped; The Likable Way
Understanding sheet metal thickness doesn’t have to be complicated. By remembering a few key rules, you can approach any project with confidence. Knowing how thick is sheet metal is a foundational skill.
First, a higher gauge number always means thinner metal. Second, the actual thickness for any gauge number changes with the type of metal. So always use the right chart. Finally, let your project’s needs guide your choice of thickness. Consider strength, weight, or formability.
Mastering these concepts is key to success. Whether your design relies on expertly formed sheet metal or needs intricate components from our Услуги токарного станка с ЧПУ, understanding material properties is the foundation of quality results.
Часто задаваемые вопросы
What is the most common sheet metal thickness?
It varies by industry. But 16 gauge (about 1.5 mm) and 18 gauge (about 1.2 mm) are extremely common. They offer a great balance of strength, weight, and the ability to be formed. You can find them in everything from car parts to computer cases.
Can I use an aluminum gauge chart for steel?
No, you must not. Aluminum and steel use different gauge systems. Steel uses the Manufacturers’ Standard Gauge. Non-ferrous metals like aluminum use the American Wire Gauge (AWG). A 16-gauge steel sheet has a completely different thickness than a 16-gauge aluminum sheet. Always use the correct chart for your material.
How thick is 16 gauge steel in mm?
A standard 16-gauge carbon steel sheet is about 1.52 mm thick (0.0598 inches). It’s important to note that a 16-gauge stainless steel sheet is slightly different. It measures about 1.59 mm (0.0625 inches). This small difference can be important in precision work.
