Why Limiting Fasteners Can Lead to Better Designs
This article was originally featured in Fastener Engineering Magazine.
Imagine you’re an engineer with the freedom to create any design you’d like with only one catch: you can only use two types of fasteners. Would this limit or simplify your design?
Simple is often best. Typically, design engineers can save costs and meet project deadlines by only using standard fasteners and limiting the type used for each application.
For Marisa Mudge, marketing manager with Mudge Fasteners, Inc. (a supply company owned by her father), the answer is simple: “The idea of designing with limited, standard parts is absolutely brilliant because of the significant time and cost-savings it, ultimately, provides,” she says.
Although Mudge is not a design engineer, she’s worked full-time at Mudge Fasteners for more than a decade (and much longer, if you add in the time she helped her dad at the company in her adolescence). So, she knows a thing or two about fasteners.
When she met an engineer from Hewlett Packard on a plane one day — who is limited in his designs by the use of only two screws — Mudge was impressed by the company’s mandate.
“One of the biggest problems companies face related to fasteners is lost parts. Typically, fasteners are the smallest part at a job site and minimal efforts are spent tracking this inventory…so the screws or bolts get dropped at construction sites, lost on manufacturing floors, or accidentally left in pockets,” she shares. “So, a project with only two standard fastener choices would have a real advantage.”
A few lost fasteners may seem like a small problem, but replacement costs can add up quickly.
“Some standard fasteners run in excess of a dollar or two a piece,” Mudge says she often gets calls from companies that suddenly need 200 or 300 additional parts after ordering 20,000 for a job. This means a lost advantage in bulk purchasing power. “Generally, these costs are significantly higher for custom fasteners.”
What makes matters worse are the lead times. “Customized parts can take two or 20 weeks to replace, which can seriously affect project deadlines,” she says. “And most of the calls we get are not directly from the design engineers or project managers. Rather, the calls come from the workers out in the field who are under pressure to have a product manufactured or installed by a certain date. The concern is the workers may develop a work around.”
What Mudge means by “work around” is the next best solution but, possibly, not the ideal fastener for the job. “This is why it’s extremely important to consider fasteners at the design stage of a project and plan for challenges during construction, such as lost parts,” she says. “It’s also why a couple of standard fasteners per application would generally make life a lot easier.”
There are additional reasons why pre-planning is important. For example, Mudge worked with one client who insisted on fasteners that would perfectly match the color of a project’s auditorium walls — and at a guaranteed cost. “In this case, we had to provide raw, non-customized fasteners because our vendor was unable to guarantee the paint required to match that exact color.”
The reason for this was simple: the environment the fasteners would be exposed could affect the paint and color, so to guarantee it was impossible. “In such cases, the architectural aesthetics can really drive up the cost of fasteners,” she explains.
The conditions fasteners are subject to, such as moisture or high heat, can also affect their reliability. “This is where standards come in, which can sometimes be an issue with custom fasteners,” says Mudge. “Standards organizations specify and test the properties of fasteners, but there are several different organizations and standards that should be adhered to depending on the application.”
For example, the Society of Automotive Engineers or SAE is primarily focused on safety regulations for the aerospace, automotive, and commercial-vehicle industries. The American Society of Mechanical Engineers or ASME provides manufacturers with guidelines and tolerances that their bolts must conform to. (View a list of the main standards organizations at mudgefasteners.com/standards-organizations.)
Marisa Mudge and her father, Paul, at the Mudge Fasteners headquarters in California.
Typically, standards are categorized into:
Products – the different types and product gaging (ex. ASME B18.2.1)
Materials and performance – specifications and strength (ex. ASTM A325)
Testing – test equipment protocol and methods of testing (ex. NASM1312)
Quality – fastener reliability (ex. ISO 9000)
“Consensus standards offer many benefits that are not covered by non-standard fasteners,” explains Mudge. This includes guidance and policies backed by significant research and expertise. “Although an engineer can anticipate performance based on material when using a custom fastener, the part is not required to meet any of the design specifications set forth by the consensus organizations, so there’s risk involved.”
Mudge recommends working with a vendor partner during the design phase of an application to identify standard parts and the ideal choice for an application.
“Typically, fasteners are the least expensive component for a job and given little forethought. But this doesn’t mean they’re unimportant,” she says. “In fact, quite the opposite is true. These small components hold an entire application together — which is one reason standard fasteners that are reliable and readily available are often the ideal choice.”
One other reason standard fasteners are ideal is to avoid unused inventory, which can happen as a product changes or evolves.
“Hewlett Packard is at an advantage by allowing engineers to design with only two screws because, even as their products change or improve, the company is never going to be stuck with dead inventory or 20,000 fasteners that they bought because procurement and design were not on the same page,” says Mudge. “It’s a wise business decision.”
Going standard
The advantages of designing applications with standard parts and limited fasteners.
Minimizes problems with inventory management
Eliminates risk of dead stock related to project design changes
Reduces procurement delays
Facilitates stock replenishment (and re-order points are simple to calculate)
Mitigates “stock out” occurrences because of limited product range
Saves time and costs