Working on the boat: Painting prep and water-tight hardware installations

24 Nov
Having a crew to help sure makes for short work
Yesterday was a very productive day! I had not one, not two, but three helpers out for the whole day and we got quite a lot done.
After having found water damage in some parts of the deck core we earlier pulled all the deck hardware, where possible squirting in thickened epoxy to fill gaps in the balsa core. Now we’re trying to protect this core from points where anything enters the deck and water might seep in. In the case of through-bolted hardware (mainly stanchion bases, for us) this is done by drilling the bolt hole through a plug of thickened epoxy which replaces the deck core in that spot.
The folks at West System Epoxy have produced an incredibly useful (and free!) book: Fiberglass Boat Repair and Maintenance, available  here. It includes detailed instructions of this procedure which involve digging out the core around your hole, plugging the bottom, and then squishing it full of epoxy. In order to save some time and use less of the expensive epoxy we made up our own technique which hopefully will still work quite well. Here’s what we did:
First, each hole was drilled oversize to clean it out and expose fresh material for the epoxy to bond to
Alex took over drilling duties after I offered to improve his haircut with the drill
      The dark material coming out of the left hole is rotten balsa while
the bright wood shavings around the right hole show the core there is still dry. 

Each hole was brushed with a liberal portion of Acetone; both to provide a clean surface for the epoxy to bond to and to dry out any remaining moisture.Then we plugged them by tapping in a small piece of wooden dowel until it was just about to pop out the bottom, taking care to be sure it cleared the balsa core area. This proved much faster than plugging each hole from the bottom, and should work equally well.

Next, we wet out all the holes with neat epoxy. This first coat of epoxy serves as a sort of primer, penetrating the surrounding area and creating a strong bond with the thickened epoxy used to plug the holes.

 While this epoxy was still wet we mixed a batch of very thick epoxy, using West System’s 406 Colloidal Silica. This epoxy was squished into each hole with a finger until no more would go in and then topped with a small piece of fiberglass cloth.

 This cloth will create a stronger skin at the top of the epoxy plug,
helping to prevent cracking or crazing.

Lastly we squished a final bit of filler over the top of the cloth and cleaned up a bit. Once the epoxy is set we will sand and/or fair it to get nice and flush with the deck and then re-drill through the center or. Some fittings which we won’t be re-using will be left filled. We did cut a couple corners by not hollowing out an area around each hole, but I think they will hold up fine, particularly as all of these will have backing plates to distribute the load.

Meanwhile, as Alex and I filled holes, Tony and Cassidy prepped and sanded the other side of the side deck for painting, which we will be doing while we have all the hardware off.

Soon after we left this ominous sky erupted in a torrential downpour. Hopefully the epoxy had already skinned up!

This article was syndicated from Safe At Harbour But Meant For The Sea: DIY Sailing with Paul Calder


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