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How To Apply MasterSeal® NP 2 Sealant

MasterSeal® NP 2 Sealant packaged in a 3.5 gallon pail
MasterSeal NP 2 Multi-Component Polyurethane Sealant in a 3.5 gallon pail

Watch how to apply MasterSeal NP 2, a multi-component, highly flexible, high performance, non-priming, polyurethane sealant (Video Transcript). Then learn more about the materials, tools and accessories required to do the job safely and efficiently.

MasterSeal NP 2 Sealant Application Video Transcript

  • Ensure substrate is structurally sound, fully cured, dry and clean
  • Use [MasterSeal P 176] primer as necessary
  • If required, install the appropriate size backer rod for the joint
  • Open the pail and remove the NP 2 activator and plastic sheet
  • Open and pour the NP 2 activator into the pail
  • Thoroughly mix for 4-6 minutes with a slow speed drill and sealant mixing paddle
  • Add MasterSeal 900 pigment into the pail
  • Continue mixing until the pigment is evenly dispersed
  • Draw sealant into caulking gun
  • Attach cone to the caulking gun
  • Cut the cone slightly smaller than the width of the joint
  • Fill joint from the deepest point, to the surface
  • Dry tool joints to create a smooth, concave shape
  • Refer to the MasterSeal NP 2 technical data guide for more information.

Sealant Application Materials, Tools and Accessories

Materials, Tools and Accessories – Shown

  • Protective Gloves – 4-mil nitrile, disposable glove
  • Protective Clothing – Long-sleeve sweatshirt
  • MasterSeal P 176 Primer – High-solids, low-VOC, solvent-based primer for priming joints and substrates
  • Brush
  • Backer Rod – Closed-cell, polyethylene foam, joint filler
  • Wooden Rod, Tapered – Used to press the backer rod completely into the joint
  • MasterSeal NP 2 Sealant, 1.5 Gallon Kit – Preferred for larger sealant applications
  • Steel Pail Opener
  • MasterSeal NP2/SL2 Activator
  • Low Speed Drill
  • Sealant Mixing Paddle
  • MasterSeal 900 Color Pack
  • Spatula – Scrape sides of color pack pigment container
  • Bulk Caulking Gun – Manual Bulk Gun
  • Bulk Caulking Gun Cone
  • Caulk Spatula – Give a smooth, concave shape to the sealed joint.

Precautionary Accessories – Not Shown

Refer to the MasterSeal NP 2 Safety Data Sheet (SDS) for more information.

  • Eye Protection
  • Face Protection
  • Respiratory Protection – In case of inadequate ventilation
  • Tool Belt.