Sikaflex 291 Marine Sealant Trials And Tribulation On The Use Of

This shows the keel housing components seperate and in the order of assembly minus the bottom of the boat which will be between the housing and the lower compression plates. Both larger components are bent as best could be as to as least approach conformity with the bottom of the boat. It is the difference in conformity that require a good spread of 'filler' or sealant and the philosophy is essentially to put on more rather than less.

This shows the bottom of the boat ready to receive the housing. Cleaning is important and the maker of Sikaflex suggest that solvents leaving a residue be avoided. We used isopropyl alcohol, a good general spirit industrial cleaner. It might have been appropriate to have roughed the area with course wire wool but this was omitted. Perhaps somewhere in the back of my mind there was a worry of detritus from such cleaning getting into the proposed work.

The Sikaflex is 'toothpasted' on in runs of approx. 7mm thickness so each of the hole is surruounded.

The messy scene after bolting down with me inside and my friend under the boat. The central plates secured with 6mm ss hex head set screws/nuts and the marginal sections with 5 mm ss cuphead hex. recessed machine screws/nuts.

Pretty much the same situation under the boat. As we worked tightening the sealant bulged from the margins and from the holes yet unfilled with bolts in no uncertain manner. This Sika flex is expensive and it was a shame to see the waste but inevitable if we were to ensure filling of any potential points for water ingress.

This would logically suggest we should have worn gloves and it is advised by the Silaflex makers. However sensible gloves would have made the job impossible, given tactile finess, the shear number of scews to brought into place with attendent washer, spring washer and Nyloc nut, and the time for my friend under the boat to capture the head for me to tighten up. The work as a piece would have failed had the set time been exceeded and as it was it became quite difficult towards the last insertions of screws. Has we had cleaned our hands at short interval with mineral turps we might've not had the dreadful affliction to our hand seen here but time for that would have been lost to the job in hand. Normally the sealant is removable from the hands IF IT HAS NOT YET CURED. Thereafter one has to wait till it can be peeled or falls off from by mechanical means from attrition. Certain web advise suggested using razor blades but this did not appeal. In our case it took THREE DAYS to dissappear. We suffered no ill effects that we could ascertain though it is mentioned that skin reactions can occur. Of course the appearances made us feel like social outcasts.