Topseal Frequently asked Questions

1. WHAT IS GLASS REINFORCED PLASTIC - "GRP"?
The glass is normally a mat of chopped glass fibres which is used to reinforce resin to make a structural "composite". This can be designed to suit almost any application.

2. WHAT IS POLYESTER RESIN?
There are a number of resins which may be used to bind the reinforcing glass together - for example, epoxies, polyurethanes, phenolics but polyesters are the most popular. This is because their properties can be easily modified, thus being easy to use at room temperature, and they are generally lower in cost than the alternative.

3. ARE POLYESTERS HAZARDOUS?
YES. They are classed as CAT 3.3 which means of relatively low hazard but that they need to be treated with care. Polyester resins are dissolved in styrene which is the source of the hazard. Styrene is inflammable (Flash Point 32 deg. C) and is classed as an irritant. Styrene has no known health effects associated with it but it has a very strong smell which most people can detect at very low levels. You should always use polyester resins in a well ventilated area.

4. DO I NEED ANY SPECIAL EQUIPMENT?
NO. You will need a mixing bucket to mix the hardener into the resin and paint brushes or rollers to apply the resin to the glassfibre. A special measuring dispenser for the hardener should be used in order to ensure accurate catalyst additions. The resin should always be mixed thoroughly once the catalyst has been added.

5. WHAT TYPE OF THINGS CAN I REPAIR?
ALMOST ANYHTING as long as it is clean and dry. Here's a list of some of the more popular repairs: TANKS, PIPES, ROOFS, VEHICLE BODIES, POND LININGS, FLOOR PATCHES, CLADDING, SIGNS, TOOL HANDLES, BOATS, GUTTERS, PLUMING AND MANY MORE ………….. CASTING APPLICATIONS Resins can also be filled with chalk or talc to make a resin "concrete" to cast a wide range of items - for example, CHESSMEN, FIGURINES, GARDEN FURNITURE AND DECORATIONS (TROUGHS), FLOORING SCREED, UNDERGROUND CABLE REPAIRS, CAR BODY FILLER PASTE, GROUTS, SIMULATED STONE AND MARBLE, BATHS AND SANITARY WARE.

6. HOW DO I APPLY IT?
To make any glassfibre items you will either need a mould to manufacture a new item (this can be as simple as a sheet of glass or melamine to make a flat panel) or a purpose-made glassfibre mould to make a boat or vehicle body or other complex moulding. The technique for all of these is always the same and specific advice can be found on this website.

7. HOW DO I REPAIR SOMETHING?
To repair anything, the glass and resin can be directly applied to the sub-straight to be repaired to form a structural weatherproof patch. For example, a pipe may be repaired by forming a glassfibre bandage around the hole or fracture. A tool handle may be repaired by forming a glassfibre sleeve or splint over the break. A water tank or boat hole may be repaired by forming a glassfibre patch over the damaged area. Details of how to do this can be found on this website.

8. WHEN CAN I NOT USE "GRP"?
In wet conditions. The resin will not cure or harden when mixed with water. The glassfibre must also be kept dry. In very cold conditions. The cure of the resin slows down as the temperature decreases. As the temperature approaches 0 deg.C, the cure will almost stop. You can adjust the level of hardener to compensate for this but resins should not be used below about 5 deg.C. On contaminated surfaces. The surface should always be clean and dry. Certain materials will poison the cure of the resin, in particular anything containing tar. For example, when lining a gutter which has been previously painted with bitumen, the surface should be sealed to ensure that the resin does not dissolve the underlying tar.

9. IN WHAT OPERATING CONDITIONS IS "GRP" UNSUITABLE?
In very hot conditions (above 100 deg.C). For example, a water boiler made from "GRP" would eventually fail. Special resins are needed for this type of application. For the same reason, a car exhaust system should not be repaired in "GRP". In highly alkaline conditions. Whilst "GRP" will withstand dilute chemicals, in particular acids, it will not tolerate prolonged immersions in highly alkaline environments.

10. HOW DURABLE IS GRP?
WE DO NOT KNOW! The oldest glassfibre laminates still in use were made in the late 1940's and 1950's. The oldest boats made from glassfibre are now over 50 years' old and no deterioration in the glassfibre can be found. We believe that an appropriately constructed glassfibre moulding will last in excess of 50 years. Where the glassfibre has been kept immersed in water, as in a boat hull, or exposed continuously to the elements, as in a boat deck, there is no evidence of deterioration of the laminate in either application.

11. WHAT IS THE APPEARANCE OF A GRP LAMINATE?
The surface finish and colour of a "GRP" laminate can be modified to simulate almost any appearance: shiny or matt, textured or smooth, any colour - including translucent finishes or metallic. Resins are already used commercially to manufacture synthetic marble, onyx, granite and any stone imaginable. "GRP" is also used for translucent roof lights and can be tinted to give the appearance of stained glass.

12. CAN I PAINT "GRP"?
YES but the surface will need to be clean and abraded before the paint will properly adhere to the surface.

13. HOW DO I DISPOSE OF "GRP"?
It is an inert material and can be easily disposed of but there are certain considerations. It should not be burned. The smoke is thick and black and has quite a strong smell. NB: Liquid resins must "always" be hardened before disposal. Once cured, they are inert and can be treated like any inert solid waste.


	Questions & Answers
	1. WHAT IS GLASS REINFORCED PLASTIC - "GRP"? The glass is normally a mat of chopped glass fibres which is used to reinforce resin to make a structural "composite". This can be designed to suit almost any application. 2. WHAT IS POLYESTER RESIN? There are a number of resins which may be used to bind the reinforcing glass together - for example, epoxies, polyurethanes, phenolics but polyesters are the most popular. This is because their properties can be easily modified, thus being easy to use at room temperature, and they are generally lower in cost than the alternative. 3. ARE POLYESTERS HAZARDOUS? YES. They are classed as CAT 3.3 which means of relatively low hazard but that they need to be treated with care. Polyester resins are dissolved in styrene which is the source of the hazard. Styrene is inflammable (Flash Point 32 deg. C) and is classed as an irritant. Styrene has no known health effects associated with it but it has a very strong smell which most people can detect at very low levels. You should always use polyester resins in a well ventilated area. 4. DO I NEED ANY SPECIAL EQUIPMENT? NO. You will need a mixing bucket to mix the hardener into the resin and paint brushes or rollers to apply the resin to the glassfibre. A special measuring dispenser for the hardener should be used in order to ensure accurate catalyst additions. The resin should always be mixed thoroughly once the catalyst has been added. 5. WHAT TYPE OF THINGS CAN I REPAIR? ALMOST ANYHTING as long as it is clean and dry. Here's a list of some of the more popular repairs: TANKS, PIPES, ROOFS, VEHICLE BODIES, POND LININGS, FLOOR PATCHES, CLADDING, SIGNS, TOOL HANDLES, BOATS, GUTTERS, PLUMING AND MANY MORE ………….. CASTING APPLICATIONS Resins can also be filled with chalk or talc to make a resin "concrete" to cast a wide range of items - for example, CHESSMEN, FIGURINES, GARDEN FURNITURE AND DECORATIONS (TROUGHS), FLOORING SCREED, UNDERGROUND CABLE REPAIRS, CAR BODY FILLER PASTE, GROUTS, SIMULATED STONE AND MARBLE, BATHS AND SANITARY WARE. 6. HOW DO I APPLY IT? To make any glassfibre items you will either need a mould to manufacture a new item (this can be as simple as a sheet of glass or melamine to make a flat panel) or a purpose-made glassfibre mould to make a boat or vehicle body or other complex moulding. The technique for all of these is always the same and specific advice can be found on this website. 7. HOW DO I REPAIR SOMETHING? To repair anything, the glass and resin can be directly applied to the sub-straight to be repaired to form a structural weatherproof patch. For example, a pipe may be repaired by forming a glassfibre bandage around the hole or fracture. A tool handle may be repaired by forming a glassfibre sleeve or splint over the break. A water tank or boat hole may be repaired by forming a glassfibre patch over the damaged area. Details of how to do this can be found on this website. 8. WHEN CAN I NOT USE "GRP"? In wet conditions. The resin will not cure or harden when mixed with water. The glassfibre must also be kept dry. In very cold conditions. The cure of the resin slows down as the temperature decreases. As the temperature approaches 0 deg.C, the cure will almost stop. You can adjust the level of hardener to compensate for this but resins should not be used below about 5 deg.C. On contaminated surfaces. The surface should always be clean and dry. Certain materials will poison the cure of the resin, in particular anything containing tar. For example, when lining a gutter which has been previously painted with bitumen, the surface should be sealed to ensure that the resin does not dissolve the underlying tar. 9. IN WHAT OPERATING CONDITIONS IS "GRP" UNSUITABLE? In very hot conditions (above 100 deg.C). For example, a water boiler made from "GRP" would eventually fail. Special resins are needed for this type of application. For the same reason, a car exhaust system should not be repaired in "GRP". In highly alkaline conditions. Whilst "GRP" will withstand dilute chemicals, in particular acids, it will not tolerate prolonged immersions in highly alkaline environments. 10. HOW DURABLE IS GRP? WE DO NOT KNOW! The oldest glassfibre laminates still in use were made in the late 1940's and 1950's. The oldest boats made from glassfibre are now over 50 years' old and no deterioration in the glassfibre can be found. We believe that an appropriately constructed glassfibre moulding will last in excess of 50 years. Where the glassfibre has been kept immersed in water, as in a boat hull, or exposed continuously to the elements, as in a boat deck, there is no evidence of deterioration of the laminate in either application. 11. WHAT IS THE APPEARANCE OF A GRP LAMINATE? The surface finish and colour of a "GRP" laminate can be modified to simulate almost any appearance: shiny or matt, textured or smooth, any colour - including translucent finishes or metallic. Resins are already used commercially to manufacture synthetic marble, onyx, granite and any stone imaginable. "GRP" is also used for translucent roof lights and can be tinted to give the appearance of stained glass. 12. CAN I PAINT "GRP"? YES but the surface will need to be clean and abraded before the paint will properly adhere to the surface. 13. HOW DO I DISPOSE OF "GRP"? It is an inert material and can be easily disposed of but there are certain considerations. It should not be burned. The smoke is thick and black and has quite a strong smell. NB: Liquid resins must "always" be hardened before disposal. Once cured, they are inert and can be treated like any inert solid waste.