Sikaflex Experiment

It will be a busy week as I am hoping to get away sailing on Friday and we are intending to change the Arthur Beale shop window on Tuesday plus we have the Riddle of the Sands Film evening on Thursday! In the meantime I still need to do some work on my yacht to get her ready for the sail. My surveyor gave the good ship a glowing report but did say that the deck planking is nearing the end of its life and that I should consider getting them replaced in a year or two. Water has got under a couple of planks and there is a bit of movement in places. I am keen that more water doesn't get under the boards and decided to try an experiment. To find where the worst places are, I normally hose down the boat and mark with chinagraph pencil those areas where the water is slow to dry out. I then use the brilliant Fein Multimaster with a deck blade to remove the old Sikaflex. This time rather than using the Sikaflex primer I have decided to treat the cleaned out and sanded grooves with three coats of G4 Damp Seal.

G4 is a bullet proof sealer that is moisture cured. Each coat bonds to the previous one so long as the coats are applied within a few hours is each other. The resulting film is totally waterproof and very tough. Prior to applying the G4 I masked the planks with Yellow Precision Masking Tape. I decided to skip the bond breaking tape this time. In fact I have always used cotton caulking rather than tape but this time I feel the most important thing is a moisture proof seal without the ability for moisture to run along the boards under the tape. I slightly overfill the grooves with Sikaflex 290iDC then run over them with a chisel at 45 degrees so the surface is flat. The following day I tear of the tape and that's it. Whether the Sikaflex will bond to the G4 is something only time will tell but as a patch up maintenance procedure it felt very good and effective.

By the way I ran short of Sikaflex by a metre or so and found a tube in my garage. It has expired in 2011 but seemed to work just the same as the new one! I get about 10 m out of a tube in gaps about 5 mm x 10 mm deep.