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  • #4462


    I am looking to put a centreboard slot gasket in/on the slot on my boat which currently does not have one. Looking on the internet I have found this is achievable but you have to take up the strips either side. This would be difficult for me as the screws on mine are badly corroded. Also looking at the boat it looks like the strips forward and aft of the centreboard case do not come close enough, there is a gap in-between them. The ends also look like they may get damaged if ran aground or similar. Any advice on how to solve this?

    Many thanks,


    [attachment=0:3q8xwnqk]CB SLOT 2.JPG[/attachment:3q8xwnqk]

    [attachment=1:3q8xwnqk]CB SLOT 1.JPG[/attachment:3q8xwnqk]


    Normally the strips overlap. Consider replacing them them (partially?).
    Replace screws. Buy your new screws slightly longer to ensure a good “bite”. Also drip some epoxy or sikaflex in the screw holes for waterproofing and better grip.


    intersting picutre: my keel has these thingies – one at each end of the slot – and it looks almost like yours did but they’ve gone missing at some point – the gaps are the right size.

    [attachment=0:2yoxxpmi]keelband thingies.jpg[/attachment:2yoxxpmi]

    maybe someone will know a) what the Y-shaped peices are called and b) where to get them.
    Aluminium strip for the main keelbands is easy-ish to come by from custom car suppliers and I suppose if you felt determined you could make up some Y-peices – PM me and I can send you some strip (I could only buy 2m which was about 1.8m more than I needed!)
    I found when I took off my slot gaskets and refitted them after painting that you need to be able to secure them all along the slot and at both ends, starting with a good secure fix on each strip at the for’ard end (John Mellor said at the cruising conference that gaskets be under a little tension fore-aft), so I suspect it MAY be good to come up with either some Y thingies or something like them, particularly at the for’ard end of the slot.

    hope the picutre helps at least.

    all best



    Thanks for the replies. I am going to try and take the strips around the centerboard slot off and see how it goes.



    Replacing a slot gasket (or fitting one for the first time) is not difficult but I am afraid those old strips have to go as the only way I know to fit them so they stay on is to trap the gaskets between the keelband strips and the hull.

    My old keel bands were in brass and the screws had lost their slots so I used a hack-saw to cut away the band (sold the bits to a scrap dealer for about £17) then having worked the stumps either side of the screw holes so they broke at the countersunk hole broke the band away from the screws. I then cut a slot in the stump of the screw or in some cases used a Mole Grip to remove each screw. I then drilled out the nasty rough hole each screw had left and filled each with epoxy filler. You can buy aluminium strip for new keelbands from Trident or P&B (quite expensive though) I suggest you get the type without screw-holes already made so you can choose where to put them to avoid the old (now epoxy filled) holes.

    If you look on the site below on the Wayfarer Institute of Technology website you will find Mike McNamara describes how to fit the new gaskets, use plenty of sealant in the screw holes. Essentially you are screwing the aluminium strip to the boat through the gasket material. I used Sikaflex 291 sealant rather than double-sided tape, mask off where you don’t want the sealant to go and maybe wear gloves as it sticks to fingers quite well.

    You will see that Mike Mc made the bands either side of the centreboard slot a bit longer than the slot so they overlap with the keelband fore and aft. That is what I did and have not had any problems yet.

    I also used the plastic strip that you sometimes see for the “bilge keels” as it was cheaper than the aluminium strip. I removed the paint on my GRP hull, used a Bostick waterproof contact adhesive, then painted over the whole lot, and they are still there too. I am not sure I would recommend sticking on strip for the centre keelband, I could imaging that being knocked off…

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