Rubber edge trim protects metal surfaces and provides sealing and insulation. Learn how to choose edge trim for your application, and how durometer (hardness), core type, and elastomer type affect product selection. Then when you’re ready, download the product catalog.
Rubber edge trim is used to finish and protect exposed metal edges while providing sealing and insulation. Applications include car doors, truck cabs, machine guards, kitchen equipment, and other sheet metal surfaces. For technical buyers and design engineers, choosing the right edge trim means selecting the right rubber based on the application requirements. Buyers and designers also need to specify rubber edge trim with wire cores or segmented cores. Durometer, or the rubber’s hardness, is also important.
Edge Trim Durometer
Rubber edge trim can be made from solid rubber, sponge rubber, or dual durometer rubber. Bulb trim, a type of edge trim, can have a softer (lower durometer) bulb and harder (higher durometer) retainer that’s pressed into place over the flange. Bulb trim that’s made from dual durometer rubber works well in applications with low-to-medium compression force and can seal out air, dust, water, and fluids while providing insulation against sound or noise.
Edge Trim Core Types
To help these rubber seals absorb impact, edge trim can contains steel wire cores or segmented steel cores. Because of steel’s ability to withstand impact under cold temperatures, edge trim with a steel wire core is a good choice for outdoor applications. Segmented steel cores often contain cold-rolled steel, which provides good elongation properties. Elongation, the amount that rubber edge trim can stretch or extend under stress, is usually expressed as a percentage of the original length.
EPDM Edge Trim
EPDM edge trim is made of a synthetic rubber that resists moisture and withstands temperature extremes. EPDM also maintains its flexibility at low temperatures, provides a relatively high degree of electrical insulation, and exhibits superior UV resistance. EPDM rubber products resist both water and steam, and provides good resistance to alkalis, acids, and oxygenated solvents. Choose EPDM edge trim for car door edges, machinery, and outdoor applications.
Elasto Proxy now offers fire-rated EPDM bulb trim that meets requirements for flame, smoke, and toxicity (FST). These fire-resistant rubber products are laboratory-tested and validated, and recommended for mass transit applications such as buses, subways, and rail. EPDM edge trim provides an alternative to neoprene rubber, an all-purpose material that also provides both flame and water resistance. Unlike EPDM, however, neoprene provides only limited flexibility at low temperatures.
TPE Edge Trim
TPE edge trim is made of thermoplastic elastomers (TPE), a group of rubber-like materials that combine the processing strengths of thermoplastics with the flexibility of thermoset rubbers. TPE is less likely to break in cold temperatures than polyvinyl chloride (PVC), but has a higher material cost than other rubbers.
Choose TPE edge trim for applications that require recyclable materials, or that require fully non-metal parts. Instead of a steel core, TPE edge trim can use a solid interior plastic for a full grip. Importantly, these fully-plastic parts also meet or comply with the requirements of the European Union’s (EU) Restriction of Hazardous Substances (RoHS) directive.
TPE rubber edge trim is lightweight, available in a variety of colors, easy-to-install, and great for window trim. You’ll find a wide variety of TPE products in Elasto Proxy’s catalog. Although TPE offers important advantages, buyers and designers need to consider its relatively poor recovery when exposed to heat and compression.
Silicone Edge Trim
Silicone edge trim is used in applications that require low toxicity, low chemical reactivity, and thermal stability over a wide temperature range. A type or family of synthetic rubbers, silicones can be specially-formulated to impart particular properties. Typically, however, silicone edge trim is used in food and beverage processing, medical, pharmaceutical, and other sanitary or hygienic applications. Choose silicone edge trim that meets your specific requirements, and remember that many silicones are available. Note, however, that some silicones are not recyclable.
Which Type of Edge Trim Do You Need?
Do you need help choosing the right edge trim for your application? Durometer, core type, and material type are important, but they’re not the only factors to consider. In addition to physical dimensions, you may need to specify a particular color or texture. Edge thickness and minimum bend radius matter, too. Elasto Proxy keeps standard edge trim in stock, and can create custom edge trim for you.
How can we help you? Download our product catalog to see schematics of standard edge trim (page 9), and learn more about our custom fabrication capabilities.
Clyde Sharpe
General Manager at Elasto Proxy
