2021.03.27 - Repairing the Mainsheet Horse
The main task for today is to repair the mainsheet horse, or traveller. The backing pads have started to delaminate, as I mentioned in a previous post, and need to be replaced.
The first thing to do is to remove the horse itself.
This should be a simple job since, as you can see from the photo, the nut is still in good condition despite the water ingress.
I simply unscrewed the nut until it reached the end of the horse both sides and then used a lump hammer to gently tap on the nut and the end of the metal horse. The horse came out without any difficulty. This photo shows the top half of the upper pad separating form the lower half as the horse is lifted.
This is the starboard side, notice how half of the pad has stayed on the horse and half has stayed on the deck.
Likewise for the port side. Notice that on the starboard side the thread shows signs of rusting whereas the port side does not. This indicates that whilst the water did get inside the boat through the delaminated pad and down through the hole in the deck on the starboard side, it did not get this far on the port side.
Here is a photo of the pad on the underside of the starboard side clearing showing the water damage. The port side is undamaged.
The rust on the thread isn't too bad, I'l use a wire brush to remove any loose rust and then either just liberally coat it in grease or see if I have any rust converter left that chemically changes Iron Oxide (rust) to Iron Phosphate or something like that and use that first.
Here I have three new pads cut from marine plywood the same dimensions as the old ones.
Two if these were screwed together and then run over a round-over router bit on the router table. The two needed to be screwed together as individually they are too thin for the router bit to work.
So these are the new pads almost ready for installation.
First, however, I need to remove the remains of the old pads. Now I made a mistake when I installed the original ones as I epoxied them to the deck. This meant that I needed to use my nice sharp chisels to remove the pads and epoxy.
This photo is of the port side pad partially removed and you see that the water did not penetrate as far as the hole. The black areas show how far the water penetrated.
Careful inspection of the hole through the deck shows that I did coat this in epoxy before mounting the horse, so although water has destroyed both the inner and outer pads, it has not damaged the deck since the exposed wood through the hole was sealed. I can only surmise that I omitted this epoxy coating on the pads before mounting them.
Once the pads were removed I gave them a light sanding in preparation for the next phase.
I wasn't too aggressive with the chisel so there is a little wood left form the pad still on the deck, but I don't think this will be a problem.
The pad of the underside of the starboard side was also removed with a chisel. This was a bit more difficult to achieve since I had to reach under the deck with both hands and use the chisel and mallet with my head over the afterdeck working blind. Still, with care I managed to remove the pad without and damage to the deck or my fingers.
One face of each pad and the sides were then coated with un-thickened epoxy and left or cure.
The cleaned up pads on the after deck were also coated with epoxy as was the underside pad.
However, the new pads will not be epoxied in place as were the originals, instead I shall seal the joint with a sealant. If the pads delaminate agin in the future I shall not have such a task to remove the pads as I have this time.
Of course, doing it this way pretty much ensures that this won't happen again, but if it does I am prepared.
That's as far as I can get for today. Later this afternoon I will apply another coat of varnish to the spars and continue work on the mainsheet horse tomorrow with more epoxy work.
Time for a fresh cup of tea.