Frequently Asked Questions

Weld-Crete® 

  1. What is Weld-Crete®?
    Weld-Crete®, the original chemical bonding agent for concrete, is a safe, easy to use surface applied bonding agent that bonds new concrete to any clean, structurally sound surface. It has been specified and used by major architects, engineers and construction companies throughout the world since 1952.
     
  2. How does Weld-Crete® work?
    Weld-Crete® is applied as a liquid and as it dries to a thin, flexible film, it forms a tenacious bond to the structural surface. The dry film is reactivated by the moisture and chemical reaction that occurs as the new concrete cures. Full bonding strength is achieved after the new concrete has completely cured.
     
  3. How is Weld-Crete® applied?
    Weld-Crete® can be applied by brush, roller, or spray. Do not dilute. When using spray equipment, the nozzle should permit a fog-type spray. Weld-Crete® should be applied in a thin, continuous, film. Do not permit Weld-Crete® to puddle in low areas.
     
  4. What surface preparation is needed for Weld-Crete®?
    The surface must be clean and structurally sound. Dust, dirt, oil, grease, wax, loose paint, efflorescence, rust, mildew, and other foreign material must be completely removed. Weld-Crete® may be painted over painted surfaces provided the paint is still well secured to the substrate.
     
  5. What coverage can be expected for Weld-Crete®?
    Between 200-300 square feet per gallon depending on the surface.
     
  6. Does temperature affect coverage?
    Yes. Weld-Crete® becomes thicker in colder weather and coverage is reduced. Spraying becomes extremely difficult in cold weather. Do not apply in freezing weather. Do not apply over frozen surfaces.
     
  7. Should Weld-Crete® freeze, will it harm the product?
    No. Weld-Crete® is freeze thaw stable; however, it is preferable to prevent freezing. Allow frozen Weld-Crete® to thaw at room temperature.
     
  8. When can new concrete be applied to Weld-Crete®?
    New concrete can be applied over Weld-Crete® when it is dry to the touch, usually within one hour, up to ten days later, provided that the Weld-Crete® film is kept clean.
     
  9. Is Weld-Crete® a water retardant or water barrier?
    Once the new concrete is fully cured, Weld-Crete® is unaffected by humidity or condensation. It is not intended for use as a water barrier. It is not recommended for use where hydrostatic pressure is present.
     
  10. What surfaces are suitable for Weld-Crete®?
    Weld-Crete® may be applied to any clean, structurally sound surface. Weld-Crete® may be applied over painted surfaces provided the paint is clean and well secured to the substrate.
     
  11. Do procedures vary when two or three coat work is applied over Weld-Crete®?
    Only the base coat is bonded to Weld-Crete®. The base coat should be a minimum of 3/8". The base coat must be allowed to dry 24 hours before the finish coat is applied to prevent flooding of the bond line.
     
  12. How can Weld-Crete® be removed from surfaces that have been accidently coated?
    Wet Weld-Crete® is easily removed with hot water. Dried Weld-Crete® is much more difficult to remove. Chemical solvents such as acetone, methyl isobutyl ketone, or cyclohexanone may be used.
     

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Plaster-Weld® 

  1. What is Plaster-Weld®?
    Plaster-Weld®, the original chemical bonding agent for plaster, is a safe, easy to use surface applied bonding agent that bonds new plaster to any clean, structurally sound surface. It has been specified and use by major architects, engineers and construction companies throughout the world since 1952.
     
  2. How does Plaster-Weld® work?
    Plaster-Weld® is applied as a liquid and as it dries to a thin, flexible film, it forms a tenacious bond to the structural surface. The dry film is reactivated by the moisture and chemical reaction that occurs as the new plaster dries. Full bonding strength is achieved after the new plaster has completely dried.
     
  3. How is Plaster-Weld® applied?
    Plaster-Weld® can be applied by brush, roller, or spray. Do not dilute. When using spray equipment, the nozzle should permit a fog-type spray. Plaster-Weld® should be applied in a thin, continuous, film. Do not permit Plaster-Weld® to puddle in low areas.
     
  4. What surface preparation is needed for Plaster-Weld®?
    The surface must be clean and structurally sound. Dust, dirt, oil, grease, wax, loose paint, efflorescence, rust, mildew, and other foreign material must be completely removed. Plaster-Weld® may be painted over painted surfaces provided the paint is still well secured to the substrate.
     
  5. What coverage can be expected for Plaster-Weld®?
    Between 300-400 square feet per gallon depending on the surface.
     
  6. Does temperature affect coverage?
    Yes. Plaster-Weld® becomes thicker in colder weather and coverage is reduced. Spraying becomes extremely difficult in cold weather. Do not apply in freezing weather. Do not apply over frozen surfaces.
     
  7. Should Plaster-Weld® freeze, will it harm the product?
    No. Plaster-Weld® is freeze thaw stable; however it is preferable to prevent freezing. Allow frozen Plaster-Weld® to thaw at room temperature.
     
  8. When can new plaster be applied to Plaster-Weld®?
    New plaster can be applied over Plaster-Weld® when it is dry to the touch, usually within one hour, up to ten days later, provided that the Plaster-Weld® film is kept clean.
     
  9. Is Plaster-Weld® a water retardant or water barrier?
    Once the new plaster is completely dry, Plaster-Weld® is unaffected by humidity or condensation. It is not intended for use as a water barrier. It is not recommended for use where hydrostatic pressure is present.
     
  10. What surfaces are suitable for Plaster-Weld®?
    Plaster-Weld® may be applied to any clean, structurally sound surface. Plaster-Weld® may be applied over painted surfaces provided the paint is clean and well secured to the substrate. The same is true of wall paper.
     
  11. Do procedures vary when two or three coat work is applied over Plaster-Weld®?
    Only the base coat is bonded to Plaster-Weld®. The base coat should be a minimum of 3/8". The base coat must be allowed to dry 24 hours before the finish coat is applied to prevent flooding of the bond line.
     
  12. How can Plaster-Weld® be removed from surfaces that have been accidently coated?
    Wet Plaster-Weld® is easily removed with hot water. Dried Plaster-Weld® is much more difficult to remove. Chemical solvents such as acetone, methyl isobutyl ketone, or cyclohexanone may be used.
     

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