Self-Piercing Grommets & Washers, the Industry’s Best Kept Secret
The sign & banner industry depends on self-piercing grommets & washers to cut through contemporary materials and set the grommet & washer in a single action. Since their first iteration, this revolutionary grommet & washer combination enabled smaller sign & banner shops to scale production, improve productivity, and ultimately their profit margins. Self-piercing grommets are most beneficial when the material does not already have holes for fasteners since there is no need to pre-punch holes in the material when using the iconic Stimpson® 405 bench press. The bench press and the self-piercing grommet do all the work upon pushing the lever down, creating reliable hole reinforcement in seconds. Most sign & banner materials, including corrugated plastic, vinyl, and polyester, are easily pierced with minimal effort.
What Are Self-Piercing Grommets & Washers?
Unlike traditional fastening systems, self-piercing grommets & washers are specially engineered to pierce the sign & banner material and set the grommet in one action. During the setting process, the interaction between the grommet & washer safely punches a hole in the material and coils the grommet in one stroke. They work in tandem with bench presses like the Stimpson 405 and the corresponding self-piercing die sets to set fasteners securely, confidently, and quickly. High-quality grommets like Stimpson’s, feature a smooth inside edge designed to reduce friction between the cord or rope, reducing premature product failure, something the end-user will appreciate. Although self-piercing grommets & washers from different manufacturers will perform similarly, it is essential to check the tooling since compatibility between manufacturers is not guaranteed.
What Are They Manufactured From?
High-quality solid brass self-piercing grommets & washers, like Stimpson’s are manufactured from cartridge brass containing 70% copper and 30% zinc. Brass grommets & washers with this metallurgical composition are incredibly durable while still retaining malleability. Since they are manufactured from a heavier gauge brass than traditional sheet metal fastener combinations, Stimpson’s self-piercing grommets & washers will withstand commercial indoor and outdoor environments for years to come.
Another popular base metal for sign & banner applications is stainless steel. Reputable grommet & washer manufacturers like Stimpson, use 304 stainless steel because it contains chromium as an alloying element to resist corrosion. Since they resist corrosion, stainless steel self-piercing grommets & washers maintain an attractive appearance regardless of environmental conditions making them an ideal choice for outdoor sign & banner applications, especially in marine environments. Stainless steel contains a high percentage of chromium and will “self-repair” when scratched or damaged, increasing the service life of the grommets & washers. Whether the application requires brass or stainless steel fasteners, both base metals retain their attractive modern appearance after installation and instantly enhance the aesthetic of any sign or banner.
Unlock New Profit Centers Using Finishes
No two sign & banner jobs are alike; the different customizations available today are almost endless. Customers can now select from various materials, print options, reinforced edges, and material thickness. As sign & banner customizations continue to grow in popularity, “decorative” grommet & washer finish options are an emerging trend and an untapped profit center for many sign & banner professionals.
Stimpson’s finish options, include plain brass, dull black, and nickel-plated, to meet changing customer demands and strict adherence to their brand guidelines. Although considered “decorative,” finishes inhibit corrosion and oxidation, making them ideal for indoor and outdoor sign & banner applications.
Plain Brass
For decades, plain brass grommets & washers remain a popular finish option because of their bright lustrous finish with a golden hue. Sign & banner professionals rely on brass fasteners because of their durability in a variety of indoor & outdoor applications.
Nickel Plating
Although similar to stainless steel in appearance, nickel plating is a popular grommet finish option because of its ability to protect the fastener’s base metal and provide a lustrous appearance. This lustrous finish offers excellent corrosion and wear resistance and is suitable for outdoor applications, including signs & banners located in harsh marine environments. Unlike other decorative finishes, nickel plating ensures that the base metal is protected even when components such as hanging clips, bungee cords with hooks, or metal cables slide across adjacent surfaces, including the nickel-plated grommet & washer.
Dull Black
Another popular grommet & washer finish option is dull black and is ideal for customers that desire an all-black or darker-colored sign or banner. This non-reflective matte black color meets military specifications, where the fasteners must reflect the absolute minimum amount of light. Unlike electroplating, a dull black finish is an oxide. Due to the oxidation process, grommets & washers with a dull black oxide have additional corrosion and abrasion protection making them suitable for indoor and outdoor sign & banner applications.
Self-Piercing Grommets & Washers Sizing Options
Stimpson manufacturers and inventories standard trade size brass and stainless steel self-piercing grommets & washers, including #0, #1, #2, 2XL, and #3. Although standard trade sizing is typical among manufacturers, it is vital to double-check the tooling compatibility. The table below includes essential sizing information for Stimpson’s brass and stainless steel self-piercing grommets & washers, including hole sizing.
BRASS SELF-PIERCING GROMMET DIMENSIONS
| GROMMET | HOLE SIZE | FLG. DIA. | L.U.F. | MT |
|---|---|---|---|---|
| #02PG | 1/4″ | .550 | .165 | .015 |
| #1SPG | 5/16″ | .630 | .200 | .015 |
| #1XLSPG | 5/16″ | .630 | .200 | .015 |
| #2SPG | 3/8″ | .750 | .200 | .015 |
| #E2XLSPG | 3/8″ | .750 | .500 | .012 |
| #3SPG | 7/16″ | .970 | .185 | .015 |
| WASHER | GROMMET | I.D. | O.D. | MT |
|---|---|---|---|---|
| #0SPW | #0SPG | .337 | .575 | .011 |
| #1SPW | #1SPG | .400 | .655 | .011 |
| #1SPW | #1XLSPG | .400 | .655 | .011 |
| #2SPW | #2SPG | .437 | .770 | .011 |
| #E2SPW | #E2XLSPG | .437 | .770 | .010 |
| #3SPW | #3SPG | .546 | .970 | .011 |
E-SERIES 304 STAINLESS STEEL SELF-PIERCING GROMMET DIMENSIONS
| GROMMET | HOLE SIZE | FLG. DIA. | L.U.F. | MT |
|---|---|---|---|---|
| #E2SPG | 3/8″ | .750″ | .200″ | .015″ |
| #E2XLSPG | 3/8″ | .750″ | .500″ | .012″ |
| WASHER | GROMMET | I.D. | O.D. | MT |
|---|---|---|---|---|
| #E2SPW | #E2SPG | .437″ | .770″ | .010 |
| #E2SPW | #E2XLSPG | .437″ | .770″ | .010″ |
Long Neck Self-Piercing Grommets & Washers for Materials Up to a ½” Thick
Unusually thick signs & banners made from corrugated plastic or vinyl require a
long-neck grommet & washer to securely fasten and display a sign or banner. While sizes may vary slightly between manufacturers, Stimpson’s extra-long self-piercing grommets & washers feature an additional 3/10 of an inch L.U.F. making them an ideal fastening solution for materials up to a ½ an inch thick. Available in brass or stainless steel, Stimpson’s extra-long grommets pierce the material and set the grommet in one single action just like tradtional self-piecing grommets & washers. The extra 3/10 of an inch prevents experienced and inexperienced press operators from inadvertently compressing or “squishing” the material during the setting process. The additional length prevents accidental compression and damage to materials due to their extra size, saving time and money.
Setting Self-Piercing Grommets with Ease
Setting self-piercing grommets & washers and swapping out tooling to accommodate different sizes of fasteners has never been easier when using the 405 bench press. It is renowned worldwide among fastening professionals because of its exceptional value, versatility, ease of setting self-piercing grommets, and overall setting quality. Although it is a manual press, the quality of work it produces equals that of hand-feed and automatic machinery and is a staple on production lines worldwide. It only takes one step to pierce a hole in the material and set self-piercing grommets & washers with ease after placing the grommet & washer on the appropriate tooling. Let’s take a quick look at the setting process.
Step 1: Put the grommet, flange up, on the top tool. It holds in place by the friction between the grommet and the tool, so push it on firmly until it stays.
Step 2: Put the washer on the bottom tool. The washer should be oriented so it sits in the groove on the bottom tool.
Step 3: Place your material over the bottom tool and position it where you want the grommet to go.
Step 3: Place your material over the bottom tool and position it where you want the grommet to go.
Partnering with Sign & Banner Professionals for Over 170 Years
Since 1852, Stimpson’s experienced team of engineers, machine tool, and customer service professionals have partnered with sign & banner professionals to solve the most complex fastening challenges. The full line of Stimpson 
grommet & washer combinations, including self-piercing, sheet metal grommets with teeth, or neck washers, and rolled rim grommets with spur washers, are in stock and ready to ship when you need them. As an ISO: 9001:2015 certified company with a near-zero defect rate, it is no wonder that Stimpson is the sign & banner industry’s premier supplier and manufacturer.
Connect with a Stimpson Stimpson fastener specialist at booth #2261 at the IFAI Expo in Charlotte, NC. Alternatively, call Stimpson today at (877) 765-0748 to ask a technical question, a quote, to place an order, or to become a Stimpson distributor. If you are ready to place an order, you can visit the official Stimpson web store, where any order placed by 3:00 PM ET ships the same day.