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| The mahogany anchor platform, stained, varnished, and ready for the boat |
Having completed my construction of the anchor platform, I could now take measures to protect it from the elements. First, I needed to epoxy-coat the bottom side of the platform. Secondly, I needed to stain the sides and the topside to achieve a uniformity of appearance in the grain. Finally, I needed to perform the time-consuming task of applying nine coats of varnish, waiting two days between each coat, and then sanding between each coat to achieve the desired result - a beautifully-finished and well-protected piece of wood. How I did all this for
Oystercatcher, my Ericson 25, is the subject of this posting.
You'll recall from the previous posting that I spent quite a bit of time shaping the mahogany to its final form.
Plain, unfinished mahogany is resistant to rot, but not as resistant to rot as that universally appreciated wood, teak. I could have gotten teak at Southern Lumber, the same place where I bought this mahogany. The only problem was that it was about 75% more expensive than the mahogany, which itself was not cheap. I just couldn't justify the expenditure, especially since I had been counseled by a wooden boat-building acquaintance to use mahogany as a substitute. This was sapele mahogany. I've spoken about this wood at length in the second part of my article on my construction of a new companionway hatch.
I applied two coats of RAKA brand epoxy to the underside of the mahogany. Epoxy will break down when exposed to UV rays over a long period of time. I didn't have to worry about this on the bottom side.
I also coated the end-grain on the forward end of the anchor platform. This would be flush against the fiberglass shelf at the stem of the bow.
I also coated the end-grain within the oval chain pipe cutout.
In my experience it takes at least two coats of epoxy to saturate any wood. More coats are often needed for the end grain.
After I had allowed these two coats to cure (over a period of at least two days), I returned with a quarter sheet sander and sanded the surface of the epoxy until it took on a smooth and translucent appearance.
The sanded areas would be receiving butyl tape, and I wanted this butyl tape to have a rough surface to which it could firmly cling.
With this epoxy-work out of the way, I could now move on to the staining of the other parts of the mahogany.
I used Pettit brand brown mahogany stain. Based upon experiments I had earlier conducted with Pettit red mahogany stain and mixtures of this red mahogany stain with Pettit brown mahogany stain, I determined that the brown mahogany stain by itself produced finishes that were closest in appearance to the finishes on the mahogany that was original to the Ericson 25. I should note that recently (Winter 2016) I was unable to find any of this Pettit brown mahogany stain on the market for the staining of some pieces of mahogany that I was adding to the interior of the boat. I had no choice but to choose Interlux Interstain, brown mahogany. This product is similar in color, but it's slightly reddish. In terms of its consistency, it is thick, just like the Pettit brown mahogany.
It's necessary to thin both of these products slightly. With Pettit, I used mineral spirits in place of the proprietary thinner (which was composed primarily of mineral spirits). With Interlux, I use naphtha and kerosene in place of the proprietary thinner (which is composed of naphtha and kerosene). Why pay 3-4 times as much money for the proprietary product when you can buy the same thing off the shelf at the local hardware store?
Using a cotton rag, I worked the stain into the grain of the mahogany. You can't just wipe this stuff on the wood and walk away. You have to keep rubbing it until the surface of the wood goes from being hazy in appearance to being clear and rich in appearance.
As you can see, the stain makes a big difference in terms of the beauty of the wood. It also evens out the stark differences that can exist between the ribbon stripes in the mahogany. I loved the gentle curves in the ribbon stripes in this piece of wood.
After I had allowed the stain to sit for a day or two, I turned my attention to the varnishing of the wood. I used Epifanes high gloss varnish. In keeping with the guidelines provided by Epifanes, I thinned the first batch by fifty percent. This allowed the varnish to soak as deeply as possible into the wood and thus seal it.
The second coat I thinned by twenty-five percent.
I carried out this varnishing of the anchor platform at the same time that I carried out the varnishing of many other pieces of mahogany. I had two other tables (not pictured). I rotated between tables, allowing at least two days drying time per table.
The third coat I thinned by fifteen percent. This mahogany might have looked good, but this job was far from finished.
Once I hit the fourth coat I was able to thin the varnish by zero to five percent. Based on experience with some of the other pieces of mahogany that I was varnishing at this time, zero percent was not acceptable. The varnish was just too unforgiving. It became tacky far too quickly, and as a result the finish was not smooth and uniform in all directions. By thinning it slightly I was able to make the varnish lie down just right. Epifanes reminds me of maple syrup.
I often had to take pictures of my work to remind me of how many coats I had applied to one piece and another.
By the time I had laid down five coats of varnish, the small imperfections in the surface of the mahogany were starting to disappear.
Every step along the way I had to sand the cured coat of varnish so that the next coat would better adhere to it. That was the unpleasant part of this process. The varnishing itself was often enjoyable. Why? Because I could walk away from my work with visible evidence of my progress - a glossy surface in place of a cloudy one.
I continued this sanding and varnishing ritual until I had applied the ninth coat. At this point the surface of the mahogany, or I should say the surface of the cured varnish, was as smooth as glass. I loved the luster of ribbon stripes beneath the glossy surface of the varnish. It took an incredible amount of labor to get to this point, but having reached it, I now thought it was all worth it.
This ends this posting on my work to preserve and protect this mahogany anchor platform on
Oystercatcher, my Ericson 25.
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