Filon is made by Kemlite Corporation, which is the largest frp manufacturer in the world and are located in Illinois. Filon is a durable semi-rigid gel coated exterior FRP [Fiberglass Reinforced Polyester] resin material. It comes in 3 shades of white and 1 shade of gray which the color is all through the product. Our color is the most popular color used in the RV industry, Polar White. The most common grades come in .040 and .060 thickness and in 8' wide rolls up to 500' long. The Filoplate gel coated surface is highly scratch, abrasion and dent resistant with excellent weathering characteristics. The maximum allowable bend radius is 7" or greater. Maintenance requires washing with liquid detergents and if you wish to wax, you can use automotive or marine waxes or use cleaners developed for use on fiberglass boats, showers and tubs. All of your high end RV's use Filon siding. I requested a technical data sheet from Kemlite and they mailed me a sample card of Filon and lots of great information. I've also made numerous phone calls to the factory techs and asked many questions. Other sources of information was acquired from Walt's RV and Mr. Bob Evans, a veteran Teardrop builder and High School shop teacher in San Bernardino, CA who's students build Teardrops as a class project.
Stabond is the suggested contact adhesive to use with Filon and I contacted the factory located in Gardena, CA for a technical data sheet and made phone calls to ask many questions. Filon expands and contracts and the same rate as the plywood mounting surface so use of other adhesives is not suggested without contacting Kemlite. Stabond [$35.00 Walt's RV] comes in 1 gallon containers and it's shelf life is 6 months from date of manufacturer. Humidity and temperature does affect it's performance so reading the technical data sheets is a must before using. It's applied using the cheapest paint spray gun, pressure type, not siphon, that you can buy [$25.00 Home Depot] and then throw it away after using it. We did not have a compressor nor the facility to spray the adhesive so we inquired about using a paint roller. By spraying, it's coverage is 500 square feet per gallon. You apply the adhesive to the Filon and plywood and let it dry to the touch. The application time is between 5 to 45 minutes, depending on many factors. If you apply the Filon too early where the Stabond is wet underneath, the solvents evaporating will cause gas bubbles within 7 to 12 hours after application and these bubbles will show through the Filon. So rolling it on will be thicker than spraying and required longer drying time. While spraying or rolling it on, the Stabond starts to spider web almost immediately. When you stick the two dry pieces together, just by barely touching them, it's permanent and you can't pull them apart. That was one of the scary things to deal with.
Rolling it out We rolled the 8'W x 40'L piece of Filon out on the front lawn and precut all the sizes we needed. It was suggested to use a carbide tipped circular saw but the thought of all that itchy fiberglass dust wasn't good. So I chose to use a long bladed tin snips and the .060 thickness was very easy to cut. Using a drywall T square made the job easier and wearing a glove protected my hands from cuts from the sharp edges. When cutting a inside 90 degree cut, drill a small hole in the corner so the gel coat won't shatter.
Kitchen Cabinet Since contact adhesives scare the living daylights out of us and in dealing with such large pieces, we decided to experiment with smaller pieces of Filon before tackling with the sides or roof. We first chose to laminate the 22"H x 55"W top kitchen cabinet. We dry fitted the piece of Filon onto the plywood and practiced on working together and planning it out step by step because the two dry surfaces of adhesive can't touch until you're ready. We found out by laying the Filon horizontal and then 'rolling' it on worked real well. As we were rolling it, pressure was used by our hands by rubbing out the air and then after the whole sheet was applied, we used a laminate roller [$10.00 Home Depot] to make sure all the bubbles were gone and the adhesive was making 100% contact. Clean up was immediately done using acetone. A new adhesive roller sleeve, disposable tray liner and cheap brush was replaced after each application.
Kitchen Siding Now that we tackled the first piece of Filon, we had to cut a more difficult piece for the inside walls of the kitchen. The radius curve at the hatch was easy to cut using the tin snips. I used the template I made for the hatch ribs as a pattern and the rest required many measurements. Everything went very well and we covered the seams with white silicone used for kitchens and baths. Now Diane can clean the kitchen using a garden hose.
Preparing the Siding We precut the sides 6 inches longer than the body length. We put the sides in position and traced the body contour and door cutout so we'd know where to apply the adhesive. Diane and I made 3 practice runs in attaching the Filon without the Stabond adhesive. We failed all 3 times! Then Diane looked at me and said, 'Let's do it!' The adhesive was drying very fast and we found out that the best method to roll it on is in one direction and not back and forth, like painting. After 15 minutes of drying time, I rubbed the adhesive by hand to pop all the tiny air bubbles and after 30 minutes, we were ready to apply the siding.
Siding support Prior to adding the siding, we attached 1/8"x2" aluminum strap into the chassis-body seam and screwed it into 3/4"x 1 1/2" boards which was 'C' clamped to the chassis frame. A 2x4 was rested on top of the 'C' clamps. My 74 year old mother stepped in to give us a hand and we couldn't have done it without her. We laid the siding horizontally onto the 2x4 and then slowly lifted it 45% until the siding slid into the grove of the aluminum strap. This helps us assure that the Filon started to adhere where it was suppose to. Then I pressed the 2x4 against the bottom of the Filon and using moderate pressure, I rolled the siding all the way to the roof edge. This method worked really well. 3 of us rubbed with our hands to make sure all the air was out and the adhesive was sticking. Then I used the laminate roller to finish it off.
It's stuck for eternity. A router with a carbide laminate trimming bit was used to trim off the edges and door opening. Acetone was used for clean up. A fine metal file was used to clean up any rough edges. Minwax urethane was used to seal all the wood around the openings of the door, window, vent, and hatch prior to installing the Filon. Even if these gaskets leak, there would be no wood damage , a typical problem with all original Teardrops.
Roof We started by cutting the Filon 8 inches wider and 6 inches longer than the required size. Using the same support method as on the sides, we started from the bottom of the front panel. We left the Teardrop hooked up to the tow vehicle and laid the Filon on top of the roof of the Blazer, adhesive side up. My dad and mom helped us at this step. Diane and I started the lower front panel and used the 2x4 to press the panel as we went up and over the top while dad and mom held the loose paneling and we just rolled it on. I was thinking of using about 12 pieces of PVC pipe and lay it on the roof and apply the Filon in the same method as applying Formica but I felt this way of rolling it on came out much easier. All the excess paneling was trimmed using the router and the vent hole was cut out. This was really messy because the router was eye level and I really got blasted with fiberglass dust. Eye protection is a must and wearing a dust mask is a good idea. We used 1 1/2" putty tape to seal under the door and vent, which is available at all RV supply stores. It was suggested to store the putty tape inside your refrigerator to make it less sticky while applying. Use a putty knife to remove any excess.