Repairing a BRe centreboard

[Rory C]

REPAIRING A BRe CENTREBOARD
Sod's Law! – maiden voyage of BRe no 25 on Ullswater, an unfamiliar cruising ground to me, in the week before the 2014 SB rally. Such excitement, so much to try so much to learn but what I didn't expect was to hit (quite hard) a covered rock well out from the shore in that part of the lake that I now know is called the narrows. Both the centreboard then the rudder bounced across the hazard and then thankfully we were back in deep water. There were no broken bits in our wake and the incident was put to the back of my mind – not much alternative! 

A few days later when we recovered the boat after the rally there was no sign of damage to the rudder and I didn't think about grovelling under a wet boat on its trailer when I was in a hurry to get unrigged and home! It was not until a couple of months later when I changed the trailer for a braked one and spent some time scrambling underneath it to adjust the support rollers that I noticed that remedial work to the leading edge of the centreboard would be necessary. (See photo 1).Exactly what would be needed was not obvious but it did look as if some water would have got into it though it didn't feel wet at the time – not surprising as the boat had been out of the water for some time and after each sail there would normally follow a period of force drying as it was trailed back to base usually at least 1+ ½ hours. Later in the season the damage was further polished trying to beat out of Brancaster Staithe (N Norfolk) with insufficient water at dead neaps!

Matt reassured me that the centreboard can be removed upwards through the slot in the cockpit. What he didn't know was that after removing the fixing screws I would have a terrible struggle to remove the hardwood cover. It had obviously been sealed with adhesive during construction and the bond with the fibreglass was stronger than that holding the hardwood fibres together. So after much levering, swearing and even using a scissor jack to prise it up the cover came away leaving plenty of wood fibres in situ.

Removing the pivot pin was relatively simple as I'm reasonably slight and the boat sits quite high on the trailer. So was lifting the board out once I realised that a sail tie could be looped round the leading edge to haul it upwards. I had no idea that the weight of the board is 34.5 kg and its C of Gravity is surprisingly shifted to the tip. There must be quite a lot of lead down there.

When I cut out the damaged tip, what had appeared to be delaminated ply (photo 2) turned out to be layers of layup separated by foam core. Happily there was no wetness nor did I come across any lead! (photo 3). This shot also shows the convenient off-cut of iroko that I used to replace the damaged section. I thought I would secure it with epoxy glue and brass screws into plugs epoxied into the holes shown. (Photo 4). (I didn't intend them to be offset but the hand-held drill drifted into the foam each time and as a result my infill is slightly out of true, even after planing and sanding to emulate the original shape).

In retrospect it would have been better to fill the holes with epoxy, let it cure and then drill pilot holes to take the brass screws but I had already mixed and applied epoxy to both the plugs and the joint so when the plugs began to turn in the holes and not draw down the screws I had to remove plugs and add more epoxy into the holes. I then pushed the insert with protruding screws down onto and into the the wet epoxy. If ever I have to revisit this mend (god forbid!) there is no way that those screws will turn for removal.

The other consequence of my mistake was that the two  2.5" brass screws did not go down as far into their countersunk holes as planned which limited the amount of fairing possible on the leading edge so you will see from photo 5 that the brass keel band that caps the iroko insert is slightly proud of the line of the leading edge. Hopefully this will not compromise balance or performance.

While the centreboard case was open I fitted a 10mm U bolt to its aft edge so that I can experiment with an inboard sheeting point for the asymmetric leading from the turning block attached to the cleat on the quarter. It's a bit OTT but has a decent aperture. (photo 6)

Before refitting the centreboard I polished it with Turtle Wax – looked and felt good but made it much more slippery to handle!  Getting it back into position is a fiddle because the 8mm line has to be rethreaded through its turning block and the deck clip before attaching the 4-part purchase. My helper was in the cockpit with 35kg of board slung in a sail tie while I struggled to rethread everything from underneath (I was loath to remove the cabin centreboard cover which is almost certainly glued and screwed as well). If ever I have to remove the board again I will attach a mousing line to the 8mm part as the board is removed.

It was as I refitted the keeper that keeps the pivot pin in place that I remembered that on its removal the sealant used in fit out had torn off a complete flake of gelcoat and I had forgotten to repair it. I sealed it with the same transparent silicone that I used to reseal the centreboard top. If I want to remove the board again it should be easier!

I hope this saga may be of use to any other BRe owner who decides to remove their centreboard at home.

[Peter Taylor]

On my BC20 (Seatern) the table covering the centreboard case sits on a gasket and is held down by wing-nuts. I believe this is standard on BC23's but not necessarily so for other Swallow Boats... I requested it when Seatern was being built following good advice from Julian Swindell.  It makes getting at the centreboard so much easier - prospective new Swallow Boat owners please note!

Peter