APPLICATIONS: Precoating

The GLEN-L EPOXY Encapsulation System depends on total encapsulation (coating and sealing) of all wood surfaces. Sometimes it is easiest to build the boat first and then coat the entire structure at one time. In other cases, it is easier to coat individual members or sub-assemblies at the workbench before they are in position, when it might be difficult or awkward to do the coating application. The framework of a boat can be erected and coated, then the planking applied. There are no hard-and-fast rules as to whether or not pre-coating is preferable; the main criterion used for pre-coating is to do it if it will save time and work over the long run.

However, members which will require bending during installation, such as longitudinals and plywood planking panels, will become more difficult to bend in place after coating. lt is also often impractical to do total complete pre-fitting, fairing, or pre-beveling, particularly along such members as chine logs, sheer clamps, and similar longitudinals without subsequent fairing and fitting. Thus, it may be easier to install the members first, then fair and fit for the planking, and then coat. The end results will be the same as long as all wood surfaces are thoroughly coated. Any members located where overhead application would be required are more easily pre-coated in a flat, horizontal position on a workbench.

Pre-coated members and sub-assemblies that have been allowed to cure will require a solvent wipe of the surface and light sanding before application of subsequent bonding adhesive. Any glue that runs onto previously coated surfaces should be cleaned up for appearance's sake before it can cure or it will be necessary to sand to remove it.

lf the builder wants to pre-coat the interior of plywood planking panels which must be bent in place, it is best to install them immediately after the surfaces have cured tack-free. As the resin sets and cures, it becomes harder, making the panel less flexible. As a compromise, some builders pre-coat only the inside of the panel (which is the hard-to-get-at surface in most boats) with just the initial coat. Exterior surfaces are then coated after the panels are installed. Interior hull areas can be recoated after the balance of the hull interior is installed.

There is an important qualification to the above procedure. Whenever epoxy is going to be exposed to sun (ultra-violet) light, it must be protected. Before painting or varnishing, it must be wiped down and thoroughly sanded. This is easier to do when the planking can be lain on a flat surface, than after it is installed. After installation, you will have to sand around frames and longitudinals, which can be a knuckle busting experience.

It is usually easiest to coat the outside of most boats after the planking has been applied rather than before, and particularly where the hull will be covered with a sheathing material such as fiberglass, which we recommend for virtually all boats.

FLOW-COATING

Flow-coating is a variation and extension of pre-coating in that a panel is not only pre-coated, but finish coated also. This technique can be used on any flat, horizontal surface, such as flow-coating the entire plywood panel which will be used to form frame gussets and floors, or using the procedure to cover flat surfaces, such as a transom, centerboard, rudder, sole, etc. The main reason to use the flow-coating procedure is to achieve a smooth surface of high thickness in one operation as opposed to applying several coats.

To flow-coat, apply an initial coat to the panel or part in the typical fashion, allowing time (about 10 to 15 minutes) for air to escape from the panel. Then while the resin is still wet, pour a large amount of resin (about a quart per 4' x 8' panel or 32 sq. ft.) directly onto the surface. Use a notched trowel to spread the resin around and then using a foam or bristle brush to lightly even out the surface. At first, it may appear somewhat rough, but after 10-15 minutes it will level out, however, it usually requires sanding for a "finished" look. Epoxy surfaces subjected to sunlight should be coated with a marine varnish or paint to prevent ultra-violet degradation. Even on interior surfaces the best finish is achieved by sanding the epoxy well and using clear varnish or similar coating over the epoxy. (see heading: Finishing)

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