3M Products & Supplies
3M Scotch-Weld Epoxy Adhesive 420, Black, Part B/A, 3 Gallon, 1 Kit/Case
Formulated to Create Rigid Bonds for Reliable Adhesion
3M Scotch-Weld Epoxy Adhesive 7240 is a high performance, two-part toughened adhesive that offers high shear and peel adhesion and outstanding levels of durability. This 2:1 mix ratio epoxy has a 45 minute work life, allowing time for adjustments and positioning of substrates and parts. It reaches handling strength in approximately 6 hours. Once cured this adhesive provides a durable bond with high shear strength to deliver better dead load holding. This product can be used in a wide range of industries including: general industrial, metalworking, transportation and aerospace. 3M Scotch-Weld Epoxy Adhesive 7240 contains glass beads to aid in accurate glue line control.
Recommended Applications
Understanding Epoxy Adhesives
Epoxy adhesives are part of the class of adhesives called "structural adhesives," which also includes polyurethane, acrylic, cyanoacrylate and others. Epoxies are formulated as liquid reactive polymers that undergo a chemical reaction when mixed and then cure to form a solid plastic material. Once the two parts are mixed in their specified ratio, they begin the curing process and offer a limited working time where the adhesive can be applied and the two surfaces positioned as needed. This work life lasts anywhere from a few minutes to several hours. These structural adhesives provide high shear and peel strengths, depending on the formula, and better heat and chemical resistance than other common adhesives. In general, epoxy adhesives have the highest overall strength and offer the best performance and most resistance to high temperatures, solvents and outdoor weathering.
Epoxy adhesives are widely used in building and home construction; aircraft and automobile manufacturing; bicycle, boat, golf clubs, ski and snowboard assembly as well as a host of home use and other applications. They are used virtually anywhere high-strength bonds are needed along with resistance to environmental conditions. These adhesives are popular for their ease of use, mechanical strength and chemical resistance. Formulations can be created to make epoxies flexible or rigid, transparent or opaque, quick setting or slow setting. The versatility with which epoxy adhesives can be formulated helps meet almost any requirement for bonding wood, metal, glass, stone and various plastics.