Sherwin-Williams Macropoxy 646

Sherwin-Williams Macropoxy 646 is a versatile high performance polyamide cured epoxy designed to fulfil the needs of both new construction and maintenance painting. It is a user friendly coating with a 1:1 mix ratio, it is fast drying, surface tolerant and available in a range of colours making it ideal for atmospheric and immersion service.

Features & Benefits

• Low VOC
• Chemical resistant
• Low odour
• Abrasion resistant
• Outstanding application properties 

Recommended Uses & Key Applications

Macropoxy 646 success is linked with its unique combination of performance, user-friendliness and versatility. It has been covering an extended number of industries and services for new construction and maintenance projects, such as: 

• Marine applications
• Pulp and paper mills
• Powerplants
• Offshore platforms
• Nuclear power plants
• Refineries
• Chemical plants
• Tank exteriors
• Water treatment plants 
• White is acceptable for immersion use for salt water and fresh water, not acceptable for potable water

* Tinting is not recommended for immersion service. 

Surface Preparation

Surface must be clean, dry, and in sound condition. Remove all oil, dust, grease, dirt, loose rust, and other foreign material to ensure adequate adhesion.

Steel, Atmospheric Service:

Minimum surface preparation is Hand Tool Clean per SSPC-SP2. Remove all oil and grease from surface by Solvent Cleaning per SSPC-SP1. For better performance, use Commercial Blast Cleaning per SSPC-SP6/NACE 3/Sa2, blast clean all surfaces using a sharp, angular abrasive for optimum surface profile 50-75 microns. Prime any bare steel before flash rusting occurs.

Steel, Immersion Service:

Remove all oil and grease from surface by Solvent Cleaning per SSPC- SP1. Minimum surface preparation is Near White Metal Blast Cleaning per SSPC-SP10/NACE 2/Sa21⁄2. Blast clean all surfaces using a sharp, angular abrasive for optimum surface profile 50-75 microns. Remove all weld spatter and round all sharp edges by grinding. Prime any bare steel the same day as it is cleaned.

Aluminium

Remove all oil, grease, dirt, oxide and other foreign material by Solvent Cleaning per SSPC-SP1.

Galvanized Steel

Allow to weather a minimum of six months prior to coating. Solvent Clean per SSPC-SP1 (recommended solvent is VM&P Naphtha). When weathering is not possible, or the surface has been treated with chromates or silicates, first Solvent Clean per SSPC-SP1 and apply a test patch. Allow paint to dry at least one week before testing adhesion. If adhesion is poor, brush blasting per SSPC-SP7/NACE 4 is necessary to remove these treatments. Rusty galvanizing requires a minimum of Hand Tool Cleaning per SSPC-SP2, prime the area the same day as cleaned.

In preparing galvanized steel substrates for the application of FIRETEX intumescent coating systems, Surface Preparation Specification SSPC-SP 16 (brush off blast cleaning of non-ferrous metals) must be followed obtaining a surface profile of minimum 30 microns. Optimum surface profile will not exceed 50 microns.