Optimize Your Manufacturing Process with Effective Assembly Planning

As mentioned in a previous article it is important to creating a testing plan for qualification, prototyping, and proving a proof of concept. The same can be said about planning manufacturing and assembly before you send your parts out for machining. This is to ensure you have properly identified your manufacturing processes and your parts are designed suitably. It also helps planning in procuring the raw materials to make your components. It will also help you identify design errors that may only be noticed during assembly for example parts of a release mechanism not fitting together as intended which may result in a downgrade in performance or an expensive redesign.

A manufacturing and assembly process mapping template can be downloaded in this link.

Figure 1 Assembly process mapping step

The basic principle of this tool is that you list out each step in how your components and assemblies are manufactured and put together. Figure 1 shows how each step is laid out. The sections of each step are described below:

• Image: Insert Image of part, or sub assembly
• Part/Assembly no: File name or title of part or assembly
• Material: What is the base material of the component
• Base material size: How big is the blank, billet, mass of filament required to make this component
• Manufacturing/ Assembly processes: List the manufacturing processes used to manufacture the components. (e.g. machining, turned, 3D printing, sheet metal) For assemblies list the process (Welded, bolted together, Press fit etc)
• Qty: Quantity of parts or assembly
• Description: Optional brief description of the component/assembly

To show you how the process mapping works we will plan out manufacturing and assembling our 1U cubesat chassis assembly (Figure 2).

Figure 2 1U Cubesat chassis

Figure 3 Cubesat 1U chassis assembly procedure

Figure 2 above is an example of how to use this manufacturing process template for manufacturing the components and assembling the 1U cubesat chassis. These would be very simple CNC milled parts and are just assembled by bolting them together. However, you may have a part with complex geometry that requires multiple manufacturing steps. For example, you could have a satellite component that will be 3D printed close to the final shape and then put the part in a CNC mill to remove the inaccuracies or improve the surface finish. Another example could be a single component comprising of individual parts being welded together.

Other steps that haven’t been highlighted were heat and surface treatments, you might have decided to use cold forging to manufacture the component to near net shape due it’s work hardening properties but in order to machine it to the final shape you need to anneal it in order to be machined by a mill, then you want to put it under other heat treatments to improve it’s properties. Other treatments can be anodising, bonding, cleaning, degreasing, bakeout for outgassing etc. Therefore, you should include these as separate steps.

Visualising your manufacturing and assembly process will help you as a designer to think how your designs will be manufactured and put together. When you identify which processes you want to use you need to ensure that your components are designed to accommodate those processes as you may end up with expensive rework or delays due to having the design rejected by fabrication. This is important if your parts require multiple different processes as you may need to design custom jigs to hold the workpiece during post machining or assembly. In addition, you may need to consider adding datums in your components to allow accurate machining of certain features.

As always, it’s best to record and plan as much as possible during your design process so that you can avoid costly mistakes but to also identify areas of improvement in further iterations. You may identify improvements in your manufacturing and assembly process that could save time and money by using different manufacturing techniques.

If you need assistance in your pocketqube or cubesat mission please don’t hesitate to contact me at Andrew.dunn@wyrmengineering.com