Cure It GRP - Hardener Addition; Hardener Quantity Chart; Hardener Addition Rules

17
Hardener addition
Hardener Addition
There are a number of important rules of thumb to follow when deciding how much hardener to add:
• Never use less than 1% even in the summer, just mix less resin at a time.
• Never use more than 4%, the gel time will not reduce any further beyond 4%.
• Neverunderestimatetheeffectoftemperature.Resinswillnotcureatorbelowfreezingandwillalwayscuremuchquickerindirectsunlight.
• When topcoating late in the day, add more hardener to allow for the lack of sunlight.
• In cold weather use winter hardener, in warm weather use summer hardener, in very hot conditions use slow hardener.
• Remember: Any hardened resin left in the bucket will exotherm. Heat is generated as the resin cures, so it should be kept well away from
other stored materials. Water can be poured over the resin to suppress the heat gain.
• Always mix the hardener into the resin thoroughly before using the resin (i.e. a good couple of minutes for a 10 litre bucket.) Failure to
do this can result in ‘streaking’ on the laminate, where streaks of uncured resin will remain visible and ultimately lead to a failure
in the laminate.
• Fastcurescanresultinaninadequatebond.
Deck/Resin
temp
22-35
o
C 18-22
o
C 12-17
o
C 0-11
o
C
Percentage
Hardener
1% Hardener 2% Hardener 3% Hardener 4% Hardener
Table of Percentages in Millilitres, Per Weight of Resin Used
Amount of
Resin
Hardener Usage
1 Kilo 10 ml 20 ml 30 ml 40 ml
2 Kilo 20 ml 40 ml 60 ml 80 ml
3 Kilo 30 ml 60 ml 90 ml 120 ml
4 Kilo 40 ml 80 ml 120 ml 160 ml
5 Kilo 50 ml 100 ml 150 ml 200 ml
6 Kilo 60 ml 120 ml 180 ml 240 ml
7 Kilo 70 ml 140 ml 210 ml 280 ml
8 Kilo 80 ml 160 ml 240 ml 320 ml
9 Kilo 90 ml 180 ml 270 ml 360 ml
10 Kilo 100 ml 200 ml 300 ml 400 ml
11 Kilo 110 ml 220 ml 330 ml 440 ml
12 Kilo 120 ml 240 ml 360 ml 480 ml
13 Kilo 130 ml 260 ml 390 ml 520 ml
14 Kilo 140 ml 280 ml 420 ml 580 ml
15 Kilo 150 ml 300 ml 450 ml 600 ml
16 Kilo 160 ml 320 ml 480 ml 640 ml
17 Kilo 170 ml 340 ml 510 ml 680 ml
18 Kilo 180 ml 360 ml 540 ml 720 ml
19 Kilo 190 ml 380 ml 570 ml 760 ml
20 Kilo 200 ml 400 ml 600 ml 800 ml
WINTER
HARDENER
WINTER/SUMMER
HARDENER
SUMMER
HARDENER
SUMMER/EXTRA
SLOW HARDENER