Monday, May 14, 2012

Fixing ‘Sandpiper’s’ Centreplate Support Bolt

Ready for applying epoxy and filler.

At last I was able to work on ‘Sandpiper’ for several hours without interruption, unlike previous days when I could only snatch brief moments. My priority was to assemble and fix the components for mounting the centreplate. I had to prepare surfaces either side of the centreplate box where the support bolt passes through it. This entailed cutting away sections of the fibreglass directly above the keelson so that the epoxy cheeks could be epoxied to the sides of the box. I discovered that the most efficient method of removing the fibreglass was to cut it into small pieces with a sharp chisel.

Before I could epoxy the cheeks to the sides of the box I had to score the surfaces being joined. This I did with my penknife. The temperature in ‘Sandpiper’s’ cabin was too low for epoxying; therefore I placed a blow heater and an electric light near to where I was working. Persistent rain did not stop play, because the boat was under cover in the garage.

After applying epoxy and filler.

I shall probably reinforce the cheeks by overlaying their edges with woven roving. I shall take care not to encapsulate the stainless steel washers, because I shall have to remove them before sealing the fittings with flexible filler.

I am hopeful that this solution for retaining the centreplate bolt will prove satisfactory, and that it will be totally watertight. I wouldn’t want water seeping into the boat. Ideally, a centreplate support bolt should be located above the waterline, but I fear ‘Sandpiper’s' is below it. I was surprised that the original structure was inadequately engineered. The only support for the bolt was the rather thin sides of the moulded centreplate box – very poor indeed.


Bursledon Blogger said...

Not an uncommon problem Bill, we had similar leaky centre board bolts on a wayfarer and our Cornish Cormorant. Both were fixed relatively watertight with gaskets, very large outer washers and reinforcements. I'm sure you're modification will work fine

William Serjeant said...


Thanks for those encouraging words.

I applied a flexible sealant to the bolt fitting today.

Before I can get the boat on the water I have a few more jobs to do.