M90 All Purpose Mortar Technical information

• Compressive strength (N/mm2 ) 
  • 1 hour 16.00 
  • 90 minutes 22.00 
  • 1 day 30.00 
  • 7 days 40.00 
  • 28 days 50.00 
• Tensile strength (N/mm2 ) 
  • 1 day 2.00 
  • 7 days 3.00 
  • 28 days 3.50  
• Coverage: Approx 1 x 400mm x 400mm standard ironwork cover and frame @ 25mm, dependant on bed depth, brickwork and substrate 
• Yield: 12.5 litres approx 
• Colour: Light grey As with all raw materials, colour variation may occur. This does not affect the consistency or characteristics of the product. 
• Unit/packaging 
  • 25kg paper bag (56 units per pallet) 
  • 25kg bucket (40 units per pallet)
• Workability: 5 – 10 minutes
• Set time: 20 minutes
• Depth: 10mm – 75mm
• Density: 2220kg/m3
• Approved for use on the London Underground and Overground
• Storage: Store in closed original packaging at temperatures between 5°C and 30°C. Avoid Frost.
• Shelf life: Shelf life in correct conditions for sealed packaging is 8 months. High temperatures and high humidity will lead to a reduced shelf life.

How to prepare surfaces for M90

1. Surfaces should be free from any contamination of oil, grease, paint, etc.
2. Remove all loose particles and work on a sound substrate.
3. Pre-soak the area with clean water prior to application to aid bond. Remove ponded water before applying the product.

How to mix M90 All Purpose Fast Set Mortar

• M90 can be mixed with a forced action mixer or by hand with an appropriate tool.
• If hand mixing is used, ensure that it is vigorous.
• 25kg of product will require approximately 3 litres of water.
• A stiff consistent mix with no slump should be achieved, ensuring all particles are well wetted.
• Mix only enough material to apply within 4 minutes.
• Never remix or add extra water.

How to apply M90 Fast Set Mortar

1. Apply the bedding material over a pre-soaked area.
2. Once mixed, M90 should be applied to the supporting structure within 4 minutes.
3. Firm well into position using a float and allow a 5mm excess thickness.
4. Place the frame onto the bedding mortar ensuring it is fully supported. Check that the frame does not overhang the mortar at any point (use suitable lifting equipment when positioning the frame). Care must be taken to prevent voids in the bedding material under the frame, especially in the cover seating area.
5. The frame should then be tamped into place ensuring the correct level is obtained.
6. Any holes within the frame should be in-filled and the flanges of the frame enveloped by a minimum thickness of 10mm of the bedding material.
7. Exposed surfaces of the bedding material should be float finished, ensuring voids are filled.
8. Remove loose materials and point the inside surface to a smooth finish.
9. Once the bedding material has reached its initial set, the backfill material can be placed.