Designing for Online Metal Bending Services

Table of Contents

In this tutorial we’ll cover all the basics for designing your files with bends.

Before you Begin

We realize everyone has a different level of knowledge and experience. We’re here to help you at every stage of the process. If you’ve never sent us a file before, or are unfamiliar with metal bending, we have a few guides you may want to check out before proceeding:

SendCutSend Design Guildelines
Metal Forming and Bending Guidelines
Designing for Laser Cutting in Illustrator

File Format

Prepare and Upload your Design File for Order Custom Metal Parts Online 1

Please upload a flat vector file such as .DXF, .AI or .EPS as you normally would. We do not require a 3D file for bending, although you are encouraged to attach a 3D rendering to your order to help us understand your project.

There are a two main things to note when designing for bending. Bend lines and bend deductions. We’ll cover both of these points and more.


Bend Lines

First you need to decide where your bend (or bends) will be on your part. Some things to keep in mind are the minimum and maximum flange length. The flange length must be at least 1/2″ (.500″) or 4x the material thickness, whichever is greater (some materials and bend angles will require longer flange minimums). The maximum flange length is 22″.

Once you’ve planned your bends, you will need to indicate where on your part you want the bend(s) to occur. We refer to these as the bend lines. On your flat file, you will indicate these lines using a different color from the rest of your design. Do not put your bends on a different layer.

Each bend direction will need to be indicated with a different color. In the example above, there are two bends, 90° up, and 90° down.


Bend Deduction

The next thing to consider is bend deduction. Bend Deduction is used to counteract material stretch caused by forming. This is unique to each material type, thickness, and bend angle. Don’t worry, we’ve created a calculator to help you make your measurements spot on.

Advanced-user note: All calculations should be for air bending not coining.

Once you have your new measurements from the bend calculator, you’ll want to adjust your design file accordingly. You will be reducing the length of your base and flange to accommodate the length of the bend itself. See the illustration below for an example. The green line indicates where the bends will occur. Keep cut out areas and holes away from these lines to avoid distortion.


Bend Colors

As mentioned above, each bend direction (up and down) should be indicated using a different color. Luckily, if you’re using our bend calculator, we’ll also show you where to use your two colors.

When you upload your file, you will then need to tell us which color to use for each direction.


Bend Angles

When designing and calling out your bend angles, it is important to note that the angles are measured on the outside of the bend. See the example below. The acute bend is measured as 130°, and the obtuse bend as 45°.


3D Rendering or Profiles

In addition to your flat, vector file, we recommend sending a 3D rendering or a side view profile to help us understand how you are expecting your bends.

If you don’t have access to 3D rendering software such as Solidworks or Fusion 360, you can always send us a sketch or profile view of your drawing in Illustrator. If all else fails, send us a screenshot of the side view from our Bending Calculator.


Exporting your design

We’ve set everything up on our end to make uploading as painless as possible. When designing in Illustrator, please send us your files in .ai format.

As always, before you upload your file, go through the usual checklist to make sure your file is ready to be cut.

File is a two-dimensional vector format file. If you're designing in Adobe Illustrator, please send us your original .ai file.

File is built at a 1:1 scale, preferably in inch-units

All text has been converted to outlines or paths

Cut-out text (reversed text) has bridges or has been stencilized

All stray points, duplicate lines, empty objects and text areas have been removed

No shapes have open contours

All shapes have been united, combined or merged

All objects are on the same layer

All holes and cutouts are at least 60% material thickness

Start your first project today!

Upload your DXF, DWG, EPS, or AI file, pick a material, get a price.

Don’t have a file? Try our Parts Builder!

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