How to design your cable assembly for manufacturability

We see it often: Engineers come to us with a design and ask, “How can I make this more manufacturable?”

You’re likely in a similar boat: Ready to move the cable assembly out of your shop and into manufacturing — but unsure how to get from prototype to mass production.

This is inherently difficult to achieve: You don’t interface directly with wiring distributors or know which connector series are further along in their lifecycle. Plus, you already track multiple vendors for the entire system or piece of equipment; it’s not realistic to add another round of part number tracking to your plate.

Instead, learn what we’ve gathered from over twenty years of part tracking, distributor relationship building and, most importantly, manufacturing — we’ve seen what can slow down production.

In this article, we’ve summarized methods for improving design manufacturability while still meeting 100% of your needs. We’ll teach you:

So, pull up your design (at whatever stage it’s at) and let’s get started.

What is manufacturability — and why is it important?

First and foremost, for a cable to be considered manufacturable, it must meet 100% of your needs. Anything else is a non-starter.

From a secondary, more technical standpoint, it’s essentially how much the design aligns with and incorporates industry standard procedures. When cable assemblies are built to IPC-WHMA-A-620 standards, you can safely assume the processes will meet necessary criteria.

If your design goes against those standards, or specifies something even stricter, that can reduce the manufacturability because it forces your manufacturer to deviate from regular processes.

This is not necessarily a bad thing; sometimes changes must be made to meet performance criteria. It only becomes a problem when the changes are so significant that accommodating them either becomes physically impossible or cost-prohibitively expensive.

What’s at risk when manufacturability isn’t factored in?

A cable assembly with extremely tight tolerances or extremely specific ratings on materials can average out to an increased price and lead time, as the time and expertise needed to build the assembly increases.

Or a design may call for improper shortcuts or incompatible parts (such as the wire AWG being too small or large for the terminal, or too many wires in one solder joint). This may provide a lower per-unit cost, but will result in lower quality, less repeatability, more waste and a higher failure rate.

The assembly may be physically possible to build, but won’t be considered realistically manufacturable.

[Read more about specific design mistakes you may be making.]

And what’s to gain?

The biggest gains will generally be price, quality, lead time — or a combination of the three.

Substituting an expensive, highly rated multi-conductor cable with a more economical alternative can improve the cost and lead time, as the materials may be more readily available or at a reduced cost.

Or the inverse can happen; you spend a little bit more on an alternative and your cost per unit increase is a small price to pay for a significant gain in functionality and quality.

Finally, if you’re able to find a better alternative material for a similar or lower price, you might be able to reevaluate your design and reintegrate the design aspects that were previously removed for cost concessions.

Step 1: Evaluate the bill of materials

These initial questions can help you and your cable assembly manufacturer ensure that specified components make practical sense for production.

We recommend asking:

If the answer to any of the questions is “No” then consider substituting with alternative parts to simplify sourcing. It might not always be possible depending on the needs of your design, but this is the best place to start for making manufacturability improvements.

Step 2: Evaluate vendor selection

Material supply and lead time issues can be swiftly avoided with manufacturer awareness.

We recommend asking:

Who is your vendor? Are they in the typical “ecosystem” of ECIA authorized manufacturers and distributors, or an independent company?

The Electronic Components Industry Association, or ECIA, is made up of leading electronic component manufacturers such as Molex and TE connectivity, and their distributors such as Digi-Key and Mouser. In addition to promoting the health of the industry, the ECIA maintains a list of authorized distributors selling new, genuine components. Source from them, and you know you’re going to reliably receive quality parts.

Occasionally, you run into a vendor outside this ecosystem. This isn’t necessarily a bad thing — they may supply an uncommon component, provide a valuable alternative source supply option or offer a more hands-on business relationship. But we generally recommend deferring to industry-recognized suppliers when possible for the aforementioned quality assurance.

These independent companies usually fall into one of two categories:

These can both be red flags for a few reasons. Mainly, their size can lead to concerns over the scalability of the inventory. With the mom-and-pop outfits, they may have limited manufacturing capabilities that can be strained by larger production orders.

With the middlemen, their supply may not be direct from the manufacturer — so it’s more limited to the whims of the market and could dry up with little notice. In both cases, this ends up increasing lead times as the supply chain becomes very inflexible.

Finally, no matter who you go with, take a moment to evaluate their web presence. Do they have their own website, or do they rely on third party e-commerce and consignment websites for listings? If the information, listings or catalog are not readily available online, they might not be the most reliable option for sourcing components.

What are you sourcing from them? Is it a custom component, or are they building a version of a commoditized connector (M8, M12, USB, etc.)?

If it’s not custom and can be reliably sourced from a variety of places, it’s better to specify the standard (as opposed to the vendor) to allow flexibility. At minimum, providing an alternate source can reduce the likelihood of part shortages.

Where are you sourcing these parts from? Is it from a sole-source, or distributor?

Websites like TrustedParts.com (which is maintained by the ECIA) and FindChips.com aggregate distributors and allow you to search for parts from multiple authorized distributors at once. If a part isn’t found on here, or is only available from a very limited source, it may be worth looking into potential alternates that are more readily available.

When was this part initially introduced?

Parts further along in their lifecycle have increased EOL risk. This can lead to critical design changes and disruption to manufacturing down the line.

On the flip side, “cutting edge” parts that just made it onto the market may not be produced at significant volumes just yet. Further, tooling options could be limited (and expensive) for these recently introduced parts.

Why was this part specified over other parts? Is there a specific design aspect that sets it apart from others, and is this aspect critical to the design?

Parts with specific features or ratings may be limited in availability. Especially with niche design needs, distributors don’t want excessive inventory on-hand of slow-moving parts.

If those ratings aren’t necessary to your design, don’t risk a slowed-down production for a feature that doesn’t actively contribute to your performance needs.

Changes for improved manufacturability may not always be necessary

Sometimes you hit the nail on the head with the first try. Or maybe your needs are very specific and you’re limited by the materials available.

For example, when you’re on the high end of material specifications (built to stricter standards, higher rated, more expensive), your pool of alternatives can go from 1,500 to five very quickly. You likely won’t have a lot of flexibility in pricing, so swapping out one supplier for another won’t make much of a difference in manufacturability.

On the lower end, it’s the inverse — there may be a large pool of alternates, but maintaining price parity can become difficult and not worth the effort.

All in all, achieving a manufacturable design isn’t an exact science; it’s about evaluating what you’ve included and why, and thinking critically about ways you can improve the end product. This article should have given you a good starting point. For further reading, this piece on common mistakes in cable assembly design will give you another framework for analyzing your project.

Has a cable assembly expert evaluated your design?

We’ve given you a lot of starter questions to ask about your design, taking you part of the way optimum manufacturability.

Let us take you the rest of the way.

A Multi-Tek cable assembly expert will take a look at your design, point out potential areas of improvement and suggest alternatives to streamline production. Get a custom cable assembly quote.