Improves Glass and Metal Adhesion and Resistance
3M™ Scotch-Weld™ Metal Primer 3901 is a one-component, metal and glass primer designed for applications using 3M™ Scotch-Weld™ film and liquid structural adhesives. Formulated to improve metal and glass adhesion, this film and liquid adhesive primer simplifies production scheduling by protecting the cleaned surfaces until the bonding operations can be completed. This product also offers resistance to environmental exposure as well as provides improved corrosion protection to metal. 3M™ Scotch-Weld™ Metal Primer 3901 features low viscosity for ease-of-application and ensures complete wetting of the film adhesive to adhered surfaces, providing an ideal application surface.
Recommended Applications
- Glass and metal applications
Protects Cleaned Surfaces until Bonding Operations can be Completed
For those applications using 3M™ Scotch-Weld™ Structural Adhesives, 3M™ Scotch-Weld™ Metal Primer 3901 ensures that surfaces remain relatively free of oxidation until the bonding application is completed. Protection from and resistance to corrosion and environmental exposure is key to successful, long-lasting adhesion.
What are 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 work life (open 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.
Industrial uses for epoxies range widely and, in addition to adhesives, include coatings and composite materials like carbon fiber and glass-reinforced composites. They are the preferred choice due to their ability to flow and conform to the work area, strong adhesion, chemical and heat resistance and exceptional mechanical and electrical insulating properties.

3M 31663, Cubitron II Net Disc 80+/180+/320+, includes 6 in discs and sheets, Job Pack, 7100251881, 100 Packs/Case
3M 76783, Cubitron II Hookit Cloth Disc 784F, 120+ XF-weight, 5 in x NH, Die 500X, 7100222757
3M 26618, Accuspray Atomizing Head Refill Pack for 3M PPS Series 2.0,Clear, 1.8 mm, 7100141416 (4 Nozzles/Kit)
3M 35790, 675L, 1" X 120", 74u, Diamond Microfinishing Film Belts, 7010509196
Standard Abrasives 724931, A/O Cross Pad, 8 PLY, 1-1/2 in x 1-1/2 in x 1/2 in, 8-32, 80, 7100105446
3M Super Abrasives Roloc Disc, 2" Type-R, Medium AO High Strength, Box of 50
Dynabrade 92209 1/8" W x 12" L 220 Grit A/O DynaCut Belt, 50/pack
ACS Flap Disc, Type 29 (Curved) Full Diamond 4-1/2 X 5/8-11 60M, 333.FD4.5-60/T29
Dynabrade 93651 1-1/2" Dia. x 1/2", 8-32 Female Center Thread, 60 Grit A/O, 8 Ply, J-DynaCut Cross Pad, 100/pack
3M 76975, Microfinishing PSA Film Disc 268L, 30 Mic, Type D, Green, 5 in x NH, Die 500X, 7000118196, 500 per case
3M 35519, Rubber Sanding Block, 2-3/4 in x 5 in, 7000126109
3M 86745, Diamond Disc, 2" Roloc, 674W, 120 Mesh, TR, 7100022116, Box of 10
3M 33176, Scotch-Brite Radial Bristle Brush Replacement Disc, T-S 80 Refill, 8 in, 7100138340, 70/Pack
3M 28830, 675L, 1/2" X 72", 74u, Diamond Microfinishing Film Belt 7010508919
3M 31959, 6450J, M125, 1" X 30", Type C, Pattern 18 Diamond Belts, 7100052712
3M 15289, 663FC, 2-3/4" X 160", 40u, Diamond Trizact Belts 7010508900
3M 71346, 675L, 1" X 120", 125u, Diamond Microfinishing Film Belts, 7010534823
3M 28656, DISC PAD FACE PLATE RIBBED, 4 IN EXTRA HARD RED, 7010326835 
