SolidWorks Bend Table: Sheet Metal Gauge Tables

December 17, 2020
EngineeringClicks

This article will teach you how to use SolidWorks bend table when working with sheet metal. We will also look at how you can create sheet metal gauge tables for SolidWorks. Anyone that has worked with sheet metal in the past knows that sheet metal properties like bend allowance, bend deduction, ben radius, K-factors, gauge thickness etc. are extremely important.

If a part is manufactured or designed with the wrong properties, then the finished product will inherently be incorrect as well. Any errors can be then multiplied when used in assemblies, such as errors in sheet metal gauge, as it is based on the weight of a sheet and not the thickness. SolidWorks can be used to help in this instance, sheet metal gauge tables are utilized to make sure that the right thickness is selected for various materials that are being used, along with the respective properties.

There are three values that are required to be able to create a sheet metal design, and they are:

Bend allowance or bend deduction (stated in the K-factor)
Bend radius
Wall thickness

By setting up a sheet metal gauge table for your project, it can dramatically speed up your workflow by making the selection of the bend radius and the right wall thickness of the material readily available. The selection of the K-factor can also be automated with the gauge table.

Bend Allowance/Deduction

The bend allowance and bend deduction refers to how the metal is behaving in the bend region. Metal is known to deform and stretch in the bending region and this is something that is essential to take into account when designing using sheet metal.

The K-factor is the most popular way of calculating the bend allowance and bend deduction, but there are multiple ways that this calculation can be done. For the purposes of this article, we will assume the K-factor is 0.5 instead of calculating it along the way.

Bend Radius

The bend radius of a material is extremely important when designing and evaluating a sheet metal design. The bend radius is dependent on two factors; the tooling that is being used and the wall thickness of the material.

An example of one certain tool that could be used to bend the sheet metal is a punch and die set. This set up would be mounted in a press.

An example of a generic punch and die set up. Source: The Fabricator — *An example of a generic punch and die set up. Source:* *The Fabricator*

By examining this diagram, we can see that the v-shaped die is located at the bottom of the press, while the sheet metal is laid on top of the die. The punch is above the die and sheet metal on the top part of the press. Once the punch is pressed down, it forces the sheet metal to form to the shape of the die.

Both the die and the punch will both have radii at the peak of their v-shape, and this will determine the type of bend that is formed in the metal. This is known as bottom bending, and is one of many ways to form a bend in sheet metal.

It is not important what type of bending is used in the process, the bend radius that is created is what needs to be focused on. This will again depend on the wall thickness of the material and the specific bending method that is being used.

Wall Thickness

Sheet metal wall thickness can be expressed as a gauge value, for example 10, 12 or 16ga. To find out what the values mean in terms of wall thickness, tables must be referenced to, like the following (Examples of sheet metal gauge tables for determining the thickness of a metal from the gauge size. Source: Metal Supermarkets):

As can be seen from the tables above, the gauge number can be used to find out the thickness of each metal. Tables like these are available for all materials. It is important to note that there can be multiple wall thicknesses and they can be confusing when entering the data into SolidWorks, watch out for mistakes!

Creating Sheet Metal Gauge Tables

Sheet metal gauge tables are available for users of SolidWorks and they are an invaluable tool. One of these tables can be created by first opening up Microsoft Excel and creating a generic table including all of the data that we discussed in the last three sections; Wall Thickness, Tool Radius and K-Factor. We can use figures from the sheet metal thickness tables above to create the following:

The above table is typical of that which might be seen in a sheet metal shop for convenience. If you did not have a sheet metal gauge table within SolidWorks, then this would be your reference for every time that you need to type values into the program.

Three more tables will now need to be created in Excel, one for each metal, these will be in the layout below:

Galvanized Steel Sheet Metal Gauge Table

Once the three tables are in the correct format as above, SolidWorks will be able to read it. Please note that once you have this done once you can just copy the file and change the values for various materials.

Now save all of these in their own separate Excel files and save them in the same folder.

Once you have the three Excel files saved, you will need to let SolidWorks know where the files are. Open the SolidWorks program, select OPTIONS / SYSTEM OPTIONS / FILE LOCATIONS. In the drop-down menu, select “Sheet Metal Gauge Table”, and select the location of your Excel files.

We will now use these sheet metal gauge tables in a new SolidWorks design!

Utilizing Sheet Metal Gauge Tables for Designing

The sheet metal gauge tables are now made and can be recognised by SolidWorks. They are now ready to be used for a design in SolidWorks, for this exercise we will be creating an 18 Gauge Aluminium U-Channel that is 1.5 x 6 x 10 inches long.

Start out by making a simple three-line sketch in SolidWorks using the above dimensions.

Once this is completed we can go to the “Base Flange/Tab” within the “Sheet Metal” tab.

The depth of the U-Channel can be entered as 10 inches as stated above, see below:

When you reach this point, you must take into account the first three points of this article;

The bend allowance/deduction i.e. the K-Factor
The bend radius
The wall thickness for the 18 gauge aluminium

We have already agreed that the K-Factor will be constant at 0.5 throughout the article, so lets focus on entering the other two values correctly.

If the sheet metal gauge tables hadn’t been already constructed and researched, now would be the time to go away and spend hours trying to find the necessary information to complete the design. These values would then have to be entered manually, opening up room for mistakes. But, we are diligent engineers and have created ours already!

In the same “Base Flange” menu that you entered the blind depth in, we can check the “Use gauge table” checkbox at the bottom that signifies that we would like to use our own gauge tables.

There will be a drop down menu beside this checkbox, once selected your three files should show up in your finest “here’s one I made earlier” moment. Choose the aluminium gaugel table as that is our material for this example.

Now set the gauge to 18 gauge from the “Sheet Metal Parameters” drop down menu. Once this is selected you can see that the wall thickness automatically fills itself in using data from our sheet metal gauge table. This will change itself to the suitable value depending on what gauge is chosen.

On the final drop down menu at the very bottom of the menu, the bend radius must be selected from the options that are taken from our table. These are again dependent on the project at hand and the specific tools that will be used. It is easy to see how having the sheet metal gauge tables saves time in a process like this. The data is pulled straight from the Excel file and none of it needs to be entered manually, once the prep work is completed before the design is started.

The green tick can now be clicked and we can be confident that the correct properties have been selected for the material that is being used in our project and the right parameters for the bend has been set.

The sheet metal gauge table is an essential tool in saving time when a professional is working on sheet metal design and needs the data at the tip of their fingers. It also reduces errors by ensuring that the correct properties and thickness of the material are being used, and the bend radius is correct for the applicable tool required. It is important to note that existing sheet metal gauge tables can always be updated and improved with more information like more gauges for the material or various bend radii for the tooling equipment.

Have you ever used a sheet metal gauge table before this tutorial? Please let us know the projects that you have worked on using this valuable technique and if you have anything to add to this article we would love to hear it in the comments section!