3M™ Scotch-Weld™ Metal Primer 3901 is a primer designed for applications using 3M™ Scotch-Weld™ Structural Adhesives. This film and liquid adhesive primer is able to improve metal and glass adhesion. Additional features of this primer include improved corrosion protection and resistance to environmental exposure for metal.
Unit of Measure

Additional Information

N/A 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 ID (Stock Number)

N/A 7000000907

Consumer UPC

N/A 00021200210877

Legacy (Stock Number)

N/A 62390135259

Sales UPC

N/A 00021200210877

Country of Origin


ECCN Number


Product Details

N/A 3M™ Scotch-Weld™ Metal Primer 3901, Red, 0.5 Pint Can, 12/Case


N/A This product, including any article that the product is composed of, does not contain at greater than 0.1% by weight a Substance of Very High Concern (SVHC) substance identified according to Article 59 of REACH. This declaration reflects the substances on the candidate SVHC list, effective July 2019.


N/A This product does not exceed the maximum concentration values (MCVs) for phthalates set under EU Directive 2011/65/EU (RoHS recast/RoHS 2), as amended by EU 2015/863, which applies to finished EEE after July 22, 2019 for Category 1-7, 10-11 products and after July 22, 2021 for Category 8 and 9 products. This means that each of the homogeneous materials within this product does not exceed the MCV of 0.1% (by weight) for each of the following phthalates: DEHP, BBP, DBP, and DIBP.


  • Improves glass and metal adhesion and resistance to environmental exposure for epoxy and urethane structural adhesives
  • Offers improved corrosion protection to metal for long-lasting performance
  • Protects cleaned surfaces until bonding operations can be completed
  • Ensures complete wetting of film adhesive to adhered surfaces
  • Easy application and quick drying