Secrets to Refinishing Mahogany Revealed

[PeteW]

My Pearson was wrecked at sea so when I got it there was no toe railing. I replaced that with 1/4 sawn mahogany planks sawed to fit the curve of the hull. Once fitted, glued and screwed to the gunwales and the rub rail pieces installed I made the major mistake of  finishing the wood in varnish.

In my haste to get the wood on there I also failed to round over the edges with a router. The plan was to get it all fitted and finish in up in place. Not the best plan in hind sight. The problem with mahogany is that it turns blonde when exposed to the sun. That red translucent hue will fade in about 6 months of UV exposure. Patching up burnt off vanish turned to wood into a mosaic of all different colors.

So I have started the task of refinishing the mahogany and after talking to every professional shipwright I could find I determined that burying your wood in West System 105 with Special 207 hardener is the best and recommended way to go.

Getting back to raw wood with the aid of a heat gun, belt sander and a block plane was the first step. You will need to connect a shop vac to all you power tools to collect dust and chips. A cardboard box strung over the side will keep the environmental impact down to a minimum.



Raw mahogany absolutely must be stained prior to applying the epoxy basecoats and you cannot use an oil based stain. Epoxy will not soak in or stick to oil residue. So forget any product from Minwax. Finally thanks to CS Ferguson Woodworking on Shelter Island they turned me on to this product.



Its  "new school" and is an acetone based line of stains by Wood Kote that come in all colors. I chose to use light brown mahogany. Rub it in and let is flash which is immediate. I figured out that if you rub it down with a clean cloth and acetone some of the surface stain will come off and up will bring up the wood grain very nicely.

Now its time to start laying on the West System105/207. The most annoying thing about 105/207 is that if it goes off in sunlight it will bubble. The trick is to put your coats on early in the AM. 900 AM worked well. 11:00 AM did not. Sand between coats with 150. Block sanding is important to get a mirror like finish. 3 coats of 105/207 is recommended.

Sand and wash the final expoxy coat and get ready to apply the first coat of varnish. You will need to varnish because 105/207 offers little UV protection. 3 coats minimum and I sand between coats with 220. So one coat a day.



The only varnish I will use anymore is Z-spar 2015 Flagship Varnish. It offers 6 times the UV protection of other varnishes. Its quirk is that it will orange peel for no good reason unless you thin it with Z-spar 120/T-10 Brushing Thinner.  If you get any blush I let it dry for a couple days before sanding.

The photo was taken after the first coat of Flagship Varnish. I had a picture that showed what it looked like with just expoxy but the digital camera would not show the color the same way my eye did. I suspect this proves how well the Flagship filters UV light.