Alternatives to Screw Connections That Won't Kill Your Tooling Budget

Mike KellerScrews are ugly…cap covers to hide screws are uglier.  There are many options for eliminating the need for screw connections in an injection molded part assembly.  Unfortunately, most will send your tooling budget through the roof.  Slides are often used to create snap connections that are completely hidden once the parts are assembled making a very clean, nice looking finished assembly.  This type of connection is used often in mass market electronics such as cell phones where the volumes make the increased investment acceptable.  For lower volume products, the higher investment is harder to swallow because it cuts into your profits.  Here are some options for clean snap or press fits that can be achieved without adding slides to your tools.

  1. Snap options – if the housing does not need to be completely closed, then snaps can be incorporated without slides.  Small openings will be visible on the outside of the parts where undercuts for the snaps need to be formed.  With some planning and industrial design work, the openings can be hidden in plain sight by integrating them into the part’s aesthetics.
  2. Press Fits – Round bosses pressed into hexagonal holes can offer very good holding power without any undercuts.  Mold changes to tighten the fit are very easy to accomplish by removing material from the flats of the hex pins.  So it is recommended to start with very little interference, and then modify the hex pin to tighten the fit.Screws
  3. Partial or full perimeter internal groove feature – with the addition of a stripper plate to the mold, a shallow undercut can be molded around the perimeter inside the part without the need for slides. This undercut can be mated with an external bead on the other part to lock the parts solidly together.

    Here’s a YouTube video on “Stripper Mold Animation” that illustrates this process:

Posted by MAGNET Ohio in General

Most Recent


February 22, 2018 by Sam Wasylyshyn

HEADLINE The survey definitively shows that product innovation leads to more growth, while “grow your own workforce” strategies will be needed to fill the major labor shortages hampering small manufacturer growth. Emerging technologies like the Internet of Things (IoT), 3D printing, and digital manufacturing are beginning to enhance innovation and productivity, but still have significant room for adoption amongst Ohio’s small manufacturing businesses. ABOUT THE SURVEY Under the direction of the Ohio Manufacturing Extension Partnership (Ohio MEP), MAGNET: The Manufacturing Advocacy and Growth Network conducted a thorough survey of Ohio’s manufacturing base. Contributing approximately 20% of Ohio’s jobs (and driving in some regions up to 50% of Ohio’s economy), and generating a disproportionate amount of export revenues and Gross Regional Product, manufacturing is critical to Ohio. Greater than 95% of Ohio’s manufacturers are small (under 500 employees), and these manufacturers need to remain competitive both nationally and internationally to ensure our economy’s health. Ohio’s Development Services Agency and the National Institute of Standards and Technology, which runs the MEP, recognizes the importance of this sector and fuels MAGNET and the Ohio MEP program to directly serve and support innovation, efficiency, and growth in small and medium manufacturers. What manufacturers need

Manufacturing is Facing a New Reality

February 06, 2018 by Sam Wasylyshyn

How Virtual Reality and Augmented Reality Can Help Keep Our Engineers Safe and Our Manufacturing Strong Recall how difficult it was to put together complex LEGO creations when you were a child or helping a child. Now, picture assembling a fighter plane from a room full of parts. Even highly trained engineers can benefit from technology to help improve consistency and quality. Virtual reality (VR) and augmented reality (AR) are making near-perfect assembly a possibility in the manufacturing space. By wearing AR glasses that use cameras, depth sensors and motion sensors to overlay images onto the real working environment, engineers and factory workers can visualize the exact bolts, parts, part numbers and instructions on how to assemble a particular component correctly. Lockheed Martin began using AR goggles and improved F-35 assembly time by 30 percent, in addition to increasing accuracy to 96 percent[1]. In order to remain competitive, businesses should consider the ways VR and AR can improve efficiency and supply chain productivity. According to a recent BofA Merrill Lynch Global Research report[2], AR platforms can provide companies up to 25 percent in cost savings on installation of equipment. Here are four ways VR/AR is disrupting the mid-market manufacturing space:

Is Technology Your Thing? Connect with TechLink

February 06, 2018 by Sam Wasylyshyn

Why should you consider TechLink? To date: More than 1,270 technology transfer partnerships brokered between companies and 110 DoD labs or centers, including all 65 DoD labs that generate patented inventions More than 600 license agreements facilitated between DoD and companies nationwide, transferring over 1,000 DoD inventions to industry Facilitated 60% of total DoD licensing agreements over the past 10 years What does TechLink Specialize in? TechLink specializes in 10 technology areas: Energy, BioTech, Materials, Sensors, Photonics, Software/Info Technology, Military Technology, Electronics and Environmental Technologies. 4 Ways TechLink can help you: Actively market DoD inventions to industry nationwide Help companies evaluate these inventions and submit license applications Facilitate communications between DoD labs and companies leading to “win-win” license agreements for both parties Maintain the nation’s only comprehensive database of DoD-patented inventions, fully searchable through Why should you believe in TechLink? Check out the TechLink technology database and the Technology Spotlight for regular updates on available technologies and contact information for the related Technology Manager. The Manager will help you assess the technology for your company needs, facilitate your connection with DoD, and walk you through the licensing process. Most DoD inventions have civilian and commercial applications. DoD technologies licensed by TechLink have generated