Flints now supply the latest HCFC free system which is very similar in characteristics to the old system but with a few minor differences. The mix ratio is 1:1 by volume but the ISO component should be added to the RES component. The best way to mix is with a paint mixer on a drill for 20 seconds. The foam will start to rise after 30-40 seconds and should be poured immediately. Foam thicknesses should be limited to 150mm for each pour. If being used in a mould use a soft wax release agent and ensure adequate vents to allow excess air or material to escape. Failure to do this could be dangerous. Rise time: 180 sec. The system is slightly more temperature sensitive than the old foams and they will cure best in temperatures up to 30C but temperatures below 18C could lead to a poor cure. We recommend that the liquids are stored in a warm area for several hours prior to use to warm right through. Therfore for best results: Warm through, accurately measure and mechanically mix.