The three areas on the older Mariners most often requiring maintenance are the centerboard, the stays and the rubber/fiberglass rub rail. In this section I will give you my experience with the three.
The most common maintenance problem with a centerboard is, over time, the board will rust and appears to flake apart. This is especially true for boats sailing in salt water. Large, flat scale can be removed by hitting the board with a hammer. Any repair work done to a board in this condition needs to have a solid metal surface as a starting point. Remove all the loose rust and flaking metal. Then , grind the surface with a grinding stone and high speed grinder. Equipment rental stores usually have what you need. Another approach is to sandblast the surface. You might be able to get it done at a local grave monument dealer or a car painting place like Maaco. In fact a place like Maaco might be willing to do both the surface preparation and the restoring. If you still want to repair it yourself, you must get raw metal exposed. Once exposed you need to coat it as soon as possible.
Epoxy resin is the material of choice for coating and protecting the board. There are several brands of epoxy resin, but the West System by Gougeon Brothers provides a complete line of fillers and catalysts to go with their epoxy resin. You can usually get West epoxy at a boat store or contact them directly: Gougeon Brothers; Box 908; Bay City, MI 48707 USA. www.westsystem.com. (989) 684 – 7286.
If the board is badly pitted, first coat it with resin mixture and let it cure. Use a mixture of resin, hardener, hard filler and chopped glass. You can make your own chopped glass by taking glass roving or glass mat and chopping the fibers up with scissors into short 1/8” to ¼” lengths. Mix this “wad” of material and spread it with a putty knife. It does not have to be smooth as you will grind it down after it hardens. You do want to avoid air bubbles and voids.
After it cures, grind it down to a profile resembling what you envision the original board looked like. If you still have low spots, apply another coat of the “wad” mixture and grind again. Once you reach a profile you are happy with, apply a final coat of epoxy to seal and smooth out the ground surface. If you want, add some graphite to the resin. West makes a special graphite additive designed for centerboards and rudders. It is best to repair one side of the board at a time.
An indication that the stays are ready to break is a slight rust stain coming from where the wire connects to the turnbuckle. Another is if one of the wires in the strain pulls out. Replace the stay immediately.
If the tension in the stays becomes loose and there is no evidence that the turnbuckle has come undone, it could be that either the stay has started to fail or the mast support is starting to give way. There are several places that will make or replace stays. I have had success with Layline (Layline; 1401 Capital Blvd.; Raleigh. NC 27603 1-800-542-5463 www.layline.com) You send them your old stay, freight collect (try to leave the turnbuckle set at the normal adjustment position) and they will make you a new one of the same length with the turnbuckle set to the center position. Be prepared, stays are expensive! The can cost $40-$50 per stay.
The purpose of the rub rail is to provide protection to the side of the boat and the area where the hull and deck fiberglass lip sections come together. Figure 1 shows a cross section view of this area. The rub rail consists of a hard inner plastic liner that fits snug over the deck and hull lips. A staple is driven through the top of the hard liner, down through the bottom of the deck and hull lips and out through the hard liner.
Pressed over the hard inner liner is the soft outer liner. It is available in either black or white. Black is the preferred liner because it does not show marks as readily as the white. Both of these liners can be purchased from Taco Mfg. (1-800-653-8567). The order numbers are V11-0232BKA100 for the outer (you need 45 feet to do a whole Mariner) and INSERT V22-0232 for the inner. The inner comes in six foot lengths.
Figure 2 shows a badly damaged deck /hull interface. Sometimes the damage is only the lip areas, but the repair requires the same process. If the damaged area is great enough to be able to see into the boat, you will need to temporarily seal the opening from the inside. You can use tape, but make sure the tape sticks well to the inside of the deck and hull.
You will next need to make a wooden mold. Figure 2 shows one made from three pieces of wood. The mold needs to be about 4 inches longer than the damaged area. The mold must be secured to the hull. I force a screw through the mold directly into the hull. The small hole the screw makes in the hull can easily be repaired later. I use a screw every 12 inches.
Figure 3 shows the mold attached to the hull. A piece of wax paper runs between the mold and the hull. Allow about five inches excess wax paper at the top, which we will use later. You might want to tape a piece of wax paper on the hull under the mold to catch the resin, which will inevitably leak out.
Now you are ready to apply the fiberglass/resin mix to the damaged area. The trick is to prepare a mixture of chopped fiberglass, resin/hardener and filler that gives strength and yet is not a gooey mess. I make my own chopped fiberglass by cutting fiberglass mat with scissors. The glass fibers need to be no longer than ¾ of an inch, so you need to do a lot of cutting. As described in the previous centerboard section, I use West System sandable filler to thicken the mix. Add the resin, filler hardener and glass in that order with mixing in-between. Apply the resin with a flat putty knife or kitchen knife as indicated in Figure 4. Push the mix into the mold/deck opening area. Bring the excess wax paper up and on top of the mix. Push down, gently packing the mix into the mold. Be careful not to push so hard that you dislodge the tape forming the back of the mold.
Allow the mix to set over night. Remove the wooden mold and grind off the excess mix with a disk grinder. This is best done with a high loaded filler/resin mix.
Slip the hard inner liner over the newly built lips and secure in place with pop rivets. Attach the flexible liner in the rear and press onto the flexible inner liner. It will clip on, but you need a mallet and the temperature needs to be above 50 degrees. A cold weather option is to preheat the liner in a tub of hot water.
Putting on the outer liner is a two person job. When stretching the outer liners over the back corners and around the bow, use a heat gun or hair dryer to help get a smooth bend.
Good Luck.
Terry Moulton