5. Mixing Matrix Premium Resin, Matrix Topcoat and Catalyst
- Premium Resin and Premium Topcoat will require stirring before the addition of catalyst
- Resin and Topcoat both require catalyst. Topcoat is not paint.
- Without catalyst the laminate will not cure and will fail
- It is essential to add the correct quantity of catalyst.
- Too much catalyst weakens cured resin and topcoat.
- Higher temperatures reduce pot life (gel time) and shorten cure time.
- Lower temperatures increase pot life and lengthen cure time.
- More catalyst reduces pot life and shortens cure time
- Less catalyst increases pot life and lengthens cure time
- Never add less than 1% catalyst and never add more than 4% catalyst
- Ideally use Premium Resin and Topcoat between 15deg C and 25 deg C
- Do not use Premium Resin and Topcoat below 10 deg C and above 30 deg C
- Use Premium Zero Resin and Zero Topcoat between 0 deg C and 10 deg C
- Catalyse Premium Zero Resin and Zero Topcoat at 2-3%
- Keep resin and topcoat cool in summer and warmer in winter
- 600gm glass mat will require approx 1.8kg of resin
- 500gm of topcoat will approx cover 1m2
- Observe shelf life and use-by dates printed on the containers.
- Record batch numbers for the Guarantee paperwork.
Measuring by weight or by volume?
- Resin, topcoat and catalyst are sold by weight but catalyst is dispensed and added by volume! For our purposes the difference is not important and can be disregarded.
- Assume that a 1L bucket of resin or topcoat weighs 1kg (or 5L = 5kg or 10L = 10kg) and use the following catalyst addition chart as a guide:
Catalyst Addition Chart (for standard MEKP catalyst)
|Catalyst Addition Chart
10mls / litre of resin or topcoat
20mls / litre of resin or topcoat
30mls / litre of resin or topcoat
40mls / litre of resin or topcoat
Gel times are approximate and will be affected by the temperature of the resins and the deck.
Catalyst – More Information
(also see Safety Section)
- Premium Resin and Premium Topcoat will gel and cure much quicker in direct sunlight.
- When top-coating late in the day add more catalyst to compensate for the lack of sunlight.
- Winter and summer catalysts (fast and slow) can be used to accommodate seasonal conditions. Maintain catalyst percentages as shown in the chart.
- Excess catalysed resin or topcoat will gel then ‘exotherm’ in the bucket. In larger quantities the exotherm with generate considerable heat and smoke and could catch fire.
- Do not place hot buckets near other flammable materials.
- Water can be poured over the resin to suppress the heat gain.
- Catalysed resin or topcoat mixes kept is a small containers have shorter pot lives.
- Larger containers with small mixes extend pot life.
- Catalyst is dangerous and should be handled with extreme care (see Safety Data Sheets)
- Always wear protective gloves, goggles and overalls when working with resins and catalysts
- Always measure and dispense catalyst from a catalyst dispensing bottle
- Do not allow catalyst to come into contact with skin or eyes
- Always have a bottle of un-opened eyewash to hand.
- Use sand or vermiculite to mop up spills. Do not use paper towels.
- If in doubt seek medical attention
Mixing and how much to mix
- Use a square-ended flat stick or paddle to mix catalyst into resin and topcoat
- It is essential to mix thoroughly. Mix 5kg of resin or topcoat for at least 60 seconds
- If in doubt double-mix topcoat to ensure there are no un-catalysed residues in bucket
- It is good practice to begin with a small quantity resin mix (1 or 2 litres) for details and bandaging. Small mixes will indicate and confirm if the correct amount of catalyst has been added to the mix
- Start the main laminate with a 5kg mix.
- When you are experienced mix larger quantities of resin - 10kg or even 20kg
- Mix smaller quantities of topcoat
- Do not mix more resin or topcoat than you can easily use within its pot-life
- Generally It is practical to aim at a gel time of around 20 to 30 minutes