Masons Mortar Ltd
77 Salamander Street
Edinburgh EH6 7JZ

Tel: 0131 555 0503
Fax: 0131 553 7158

Masons Mortar Ltd
Unit I, Woodville Court
Woodville Street
Glasgow G51 2RL

Tel: 0141 445 4812
Fax: 0141 445 8898

Masons Mortar Ltd
Block 2
Woodend Industrial Estate
Cowdenbeath, Fife

Tel: 01383 514 460

Masons Mortar Ltd
Unit 11
Brough Park Trading Estate
Fossway, Newcastle upon Tyne

Tel: 0191 908 9234

1. Product description
Mineral dry bagged masonry restoration repair mortar based on hydraulic binders with special aggregates

2. General application and uses
St.One Sandstone restoration mortar is a natural sandstone / masonry replacement mortar for surface repair or replacement of weathered and damaged stone that can be tooled and finished to match the original in both colour and texture - it may also be used to cast members.

3. Material Properties
• Bulk Density 1.35g/cm3
• Water demand 3.5-4.5L per 25KG
• Open time 60mins
• Compressive strength 7.25N/mm2
• Flexural strength 2.38N/mm2
• Modulus of Elasticity 7690 MPa
• Capillarity 2.06 g/dm2.min 1/2
• Vapour permeability 0.75 gxm2xhx mmHg

4. Application instructions
Ambient and materials / surface temperature range to be within 50C - 300C - out with these ranges consult our technical department.

5. Background / substrate preparation
• Chisel out defective substrates back to a sound base using a toothed chisel.
• Cut edges to straight lines on flat work, ellipses on curved work, mortised with back chamfer to not less than 5mm depth
• Where straight or ellipse line work is not possible, ensure mortar does not finish to a feather edge
• All backgrounds must be free of salts, dust, loose or friable materials
• Clean cavities with mild grit blasting, pressure washing, and/or brushing with a stiff bristle brush.
• Dampen, to control suction by pre-wetting.
• No standing water, remove with a sponge

6. Mixing
• For best results use hand held drill or whisk type mixer. Mix dry powder into water gradually, start wet, work to drier consistency. Do not short mix, short- short mixing requires greater water content and will lead to bleed or shrinkage. Over mixing will weaken the material. Mix for 3-4 minutes with suitable mechanical means. If hand mixing mix only small amounts and ensure the materials are properly mixed, usually around 4-5 minutes of vigorous mixing.

7. Application (one or multiple coats)
• Apply an initial layer 3mm or so with some pressure to the background, then lay the rest of the St.One up against this to the desired thickness, this can be laid on or thrown on but should always be on to the fresh closed in base coat.
• Generally up to 40mm can be applied in a single pass, including the 3mm base layer, however it is always best to divide up thick layers - 20mm or more into 2-3 or even 4 layers.
• Allow at least 2 hours between each application, work out to gradually thinner layers towards the face, the final coat must be capable of being tooled to an adequate depth to match the existing masonry and should be at least 5mm thick at the shallowest point.
• Ensure the final application is at least 2mm proud of the finished surfaces to allow for tooling - scraping, shaping back.

8. Finishing
• Finish with appropriate tools as the mortar takes its initial set, 4-8 hours depending on ambient conditions.
• Shaping with trowel edges, sculpting tools, sanding blocks, tungsten carbide abrasive sheet, scratch floats and the like can be done from 4 to 24 hours. For uniform perfect colour across all the repairs the method of finishing and timing should remain consistent to avoid differential hydration.
• All repairs should be overfilled and cut back, where a tighter finish, closed down is required, scrape back and close down with a stainless steel float or a dry sponge while still sufficiently green to achieve the desired results.

9. Consumption
• 17-18KGs per M2 at 10mm thick
• 4.4 lbs per Square foot at ½ inch thick

10. Clean up
• Wash tools with clean water immediately after use

11. Colour matched or colour packs
• As supplied, either through coloured or with colour pack for onsite mixing
• Through coloured dry bagged product, take materials as required and mix with water, colour will remain consistent throughout the depth of the material
• Colour packs are supplied for mixing with 5, 10 and 25 KG units of base St.One sand stone
• Empty the colour pack into mortar which has already been mixed to a stiffer than normally usable consistency, turn package inside out and clean off any residual pigments into the wet mix, dispose of colour packaging thoughtfully
• Proper protection must be maintained throughout the curing process, colour variation will occur if differential hydration takes place. After placing keep work protected from strong sunlight, drying winds, rain and frost until properly cured.

Hazardous substances classification

• R 38: Irritating to the skin
• R 41: Risk of serious damage to the eyes
• S 2: Keep out of reach of children
• S22: Do not breathe dust
• S24/25: Avoid contact with skin and eyes
• S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice
• S37/39: Wear suitable gloves and eye / face protection
• S46: If swallowed, seek medical advice immediately and show this container or label
Transport Hazard Class
EC waste code no 170101
Any residue must be emptied out of bags or containers before recycling.
Solidify any residual material with water and after consulting the relevant authorities, dispose of in a construction material land fill site.