How to Create High-Quality Drawings and Engineering Files for Manufacturing Services

At Alchemy Industrial, we pride ourselves on our customer service and engineering expertise. However, as much as we hate to admit it, we can’t read your mind! 

Our goal is always to give you functional, high-quality parts that meet your needs. But unless we know what your needs are, we can’t deliver on that promise. 

You’ll have significantly more control over the outcome of a part when you provide us with a high-quality drawing and a world-class engineering file. Including all the correct details and context makes the entire manufacturing process much smoother. 

How to Create an Optimal Drawing for Manufacturing Services

The purpose of your drawing is to convey the manufacturing requirements for your part, and every bit of information you include should serve a functional purpose.

The best drawings adhere to a recognized standard, such as ASME Y14.5 or ISO. The goal is to ensure that anybody who sees your drawing can interpret the intended design. 

Here are three critical elements to include in your 2D drawings: 

• Title block. The title block contains crucial information like the part and revision numbers, a description of the part, materials, standardized dimensioning, and GD&T schemes. Customers often provide drawings that include dimensions but not tolerances, in which case most manufacturers refer to the title block for tolerance requirements. Just be sure to call out specific tolerances for features with tighter tolerances than those mentioned in the title block.
• Revision block. Revision practices can vary from one company to the next, but it’s best to make sure any revision changes are updated across both your models and your drawings. Although the title block includes the revision number, there should be a separate revision block with notes about the changes. We also advise customers to flag all changes at the points in the drawing where they made them.
• Additional notes. Call out any specifications that are impossible to convey via dimensions. Coating and heat-treating requirements, for example, are specifications that need callouts with some detail to ensure your manufacturer gets them right.

What to Include in Your Engineering File

Your partner for manufacturing services needs more than a drawing to build an accurate and functional part. Sending a file that contains additional context is helpful for the manufacturer and can reduce time on back and forth communications with customers.

The engineering file should include:

• Bill of materials (BOM). A BOM informs how a part or product comes together. It contains key information about materials, parts, components, assemblies, sub-assemblies, and more. Some customers provide flattened BOMs, meaning they’ll show the entire product represented in one drawing. But flattened files aren’t structured to support the manufacturing process. Instead, we recommend providing separate drawings for each sub-assembly listed in the BOM.
• Support narrative. When sending engineering files for a complete assembly, including the design intent is critical. What are you building, and what is its purpose? What are the relevant constraints and regulatory or quality issues to consider? This narrative, which is usually a text document, provides essential context for the manufacturer. 
• 3D model. It’s always best to include a 3D model in addition to a 2D drawing. While the 2D drawing provides critical information like dimensions, part numbers, and tolerance specifications, the 3D CAD file is necessary for manufacturing services providers to produce fast and accurate digital quotes.  

There are plenty of good reasons to be diligent about part drawings and engineering files. Providing high-quality documentation not only presents a clearer picture of the part you need, but it also keeps important information together all in one place. Once you have a comprehensive part drawing and file, you’re ready to have your part made by any manufacturing services provider whenever you need it. 

Alchemy Industrial is happy to help you assemble your drawings and engineering files—and hopefully make your parts, too!  Contact us today to learn more about our manufacturing services.