Revarnishing the Bowsprit, oh joy more sanding.

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Pole after second coat

When we refitted the boat, we decided that the bowsprit and boom were in ok shape, not brilliant but ok. The pole in particular has started to take a bit of a battering, and the resin coating was flaking off. As we are stuck in a hard lockdown in Ireland and no sailing is likely for a while, T-Bear decreed that it needed to be sorted. He also decided he wasn’t going to do any of the work. He wants to keep his fur clean apparently.

Flaky pole end.
Flaky pole end.

The first thing to do was to sand the pole back to the bare composite. The outer finish as far as we can figure out was the original resin finish from the female mould used to make the pole. It doesn’t look like the pole was finished beyond how it came out of the mould. Sanding a round pole needs to be done carefully, it is very easy to flat the pole accidentally. To avoid that, the sanding technique is to roll around the pole in the typical X pattern used for hull fairing. See video for demonstration.

Sanding off the spinnaker pole.
Pole waiting to be varnished

It took about 5 hours to sand the pole down to bare composites with 120 Grit sand paper. We used the soft sand blocks from the original boat detail sanding, as they have a little give in them to mould around the pole a little bit. The end result was a consistent finish across the carbon and no noticeable flat spotting. Next thing was to prepare the pole for varnishing.

We are using Epifanes Two Part Polyurethane UV Coating/Varnish. We decided to use this for a couple of reasons, firstly came down to supply it is proving difficult to source high performance marine products at the moment as most come over from the UK. The main Epifanes importer is 5 minutes down the road so that made life easier. Secondly Polyurethane varnish tends to more flexible and resilient to knocks etc than epoxy finishes. Which feels like a good idea for a bowsprit.

Preparation involves the following, firstly cleaning the pole with water to remove the surface dust from the sanding. This should be done a couple of times to make sure all of the dust is removed. Then the pole needs to suspended somewhere where it is possible easy access top and bottom. The room needs to be at a warm temperature, ideally 20 degrees. Then final step is to clean the pole with Epifanes thinners to remove grease etc before starting.

First coat of Epifanes

To get the best results, actual varnishing needs to be done carefully and slowly, it’s not to be rushed. Fortunately Ali is an expert in doing this and she explained how to do it. So the objective is to get a even coating, to do this first paint the varnish on going vertically first, starting a head of end of the pole and working backwards. Then draw the brush length ways again towards the end of the pole. By doing this you get an even distribution across the pole. We worked in 30-40 cm sections, constantly working from one end to the other.

It takes about an hour to do the whole pole. While working with these chemicals it is really important to use a mask which filters vapours. Our first mask is great for dust, but not vapours, after an hour of working with the Epifanes in a closed garage Tris wasn’t feeling to well and it took an hour or so for his head to clear. After that it is important to leave the varnish in the warm space for around 24 hours, before adding another layer.

Got runs on the first layer.

Annoyingly and probably as a result of the fumes, we got runs on the last part of the pole on the first layer. So we had to sand them out before adding the second coat.

Setting up subsequent layers it is really important not to rush, any dust in the air seems to be automatically attracted to the first layer when you clean it with thinners. So it is worth taking the time to let everything settle again before starting to varnish.

We plan to do three layers, and will post images of the last coat.

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