Technical: Permanent Seam Repairs

A high-tech tape from EternaBond is an
aggressive adhesive with attitude
By Doug Marion

To most RVers, nothing is more annoying than a pesky water leak, especially one that pops up in a place where there are no repair centers. In the old days, one would squirt on some silicone or, in pure desperation, cover the area with duct tape, but these on-the-spot repairs were very temporary. If you have a rubber roof, using the wrong sealing material can cause more problems that the initial leak.

A new product on the market, called EternaBond, is designed to stop most leaks, and it will not compromise the roof material. EternaBond is a high-tech adhesive that is sold in tape form and is available with three exterior coverings: woven fiber, soft aluminum and mixed-polymer (plastic). If affixes itself permanently with minimal hand pressure in temperatures as low as minus-20 degrees F and is said to be perfectly safe for all RV roofs and side walls.

On vertical surfaces, it will not sag -- even at temperatures approaching 200 degrees F -- according tot he manufacturer. To use, it requires no mixing, pouring or preparation other than basic cleaning of the surface with mild soap, water and a drying towel. It is one of the most aggressive adhesives available and can be installed directly over old seams.

EternaBond's tape form is a result of being extruded (compressed and flattened) through a die machine. It is then permanently laminated to the aforementioned top cover and a release-type material is attached to the bottom. When applied properly, the seal is permanent and said-to-be everlasting. It was originally designed and engineered to create totally sealed and corrosion-proof pipes that are used under water.

The thickness of the tape is determined by the exterior covering. The woven-backing (WB) and mixed polymer (MP) tapes are 30 mils thick, and the soft aluminum (A-Seal) backing is 20 mils thick. All are available in rolls 4 inches wide and 50 feet long. A-Seal and MP-Seal can also be special-ordered in 2- and 6-inch-width rolls.

>EternaBond also offers a Moldable Seal that has no covering. Instead, it's sticky on both sides and is designed to be used as a seal when installing windows or roof vents. This material can also be rolled or folded into a bead or a square for areas needing a thicker gasket. It is available in rolls 60 mils thick, 2 inches wide and 50 feet long. It can be special ordered in 4- and 6-inch widths.

The company also offers an Emergency Repair Kit, which includes 36-inch lengths of each type of tape and 72 inches of Moldable Seal. It's packaged in a reusable plastic container, with instructions.

A 50-foot Seam Repair Kit includes a 4-inch-wide 50-foot-long roll of WB-Seal and one quart of EternaBond tintable UV Protector. A 200-foot Seam Repair Kit has four rolls of WB-Seal and one gallon of UV Protector.

The tapes can also be purchased by individual rolls, or by the case. EternaBond tintable UV Protector sells by the quart or gallon.

While most users may consider the EternaBond tape a temporary fix for on-the-road maladies, it actually can work as a permanent seam sealer. When using WB-Seal on areas that are exposed to sunlight, two coatings of EternaBond UV Protector Sealer liquid (included in the Seam Repair Kits) is required. The installer can either paint over the sealer or tint it to match the exterior at a local paint store by mixing in the liquid tint coloring designed for latex paint -- starting at 75 percent less tint than required for latex paint.

All other EternaBond tapes are UV protected and require no other coatings, but can be painted if so desired.

The installation process is simple, but like many other projects, the best results can be attained after proper preparation. After cleaning the work area, measure a length of EternaBond tape that will cover the seam to be sealed. It helps to place a piece of masking tape on each side of the seam that will receive the EternaBond to serve an an alignment guide.

You'll need to work carefully because this stuff really sticks, and only remove the working portion of the release liner at a time. As a matter of fact, once the tape hits the surface, it's almost impossible to remove. The holding power is incredible, but the tape will not adhere to silicone. The tape can also be applied to a wet surface if need be, but the set-up time will not be instantaneous. It takes only a few hours to seal the roof of an average-size rig.

Whether used to seal the roof of an RV that has seen better days or carried along in the rig for use in case of an emergency, the EternaBond tape offers a viable solution to the age-old problem of sealing out moisture. The product is very effective, and used properly, is much more attractive than slopping the area with liquid or silicone sealers. The company stands behind the product with a satisfaction guarantee. TL

As appearing in Trailer Life Magazine, April 2000, page 74-76.