Manual Mixing BB BINDER® RB 520 is a two component epoxy Sealer. Mix thoroughly 5 parts of Resin with one part of Hardener by volume for at least 5 minutes (If not mixed properly the sealer will not perform well or will not harden at all.) Mixing should be carried out by using a flat laddle / spatula or similar tool. Double potting should be carried out for best results (mix material in 1 container. Pour mix into another container and mix well again). The well mixed mixture should be applied within 20-25 minutes. Leave for at-least 1 hour for 70-80% bond strength. Product gains full bond strength in 24 hours. Machine Mixing Adjust the machines mixing ratio as follows, 5 parts resin and 1 part hardener by volume. No heating arrangement is required. Leave for at-least 1 hour for 70-80% bond strength. Product gains full bond strength in 24 hours