Delaminated Filon Trailer Blues

The joys and perils of the fiberglass trailer

Do you own a fiberglass, or Filon, trailer? They first became popular in the 90s. Since then, several companies have developed fiberglass trailers. Their popularity is again on the rise, as people are attracted to their smooth sleek look versus the corrugated aluminum. However, with that said, some problems may arise concerning them. At Hemet Valley RV, we stock Lamilux 1000 and 4000.

luan unicore differencesIf you own a Filon trailer, have you ever wondered why your front wall has “fallen apart” and not your side or back walls? Filon trailers tend to have delamination issues. This is due to the difference between Luan and Unicore. The front wall is Unicore and the rest is Luan. Put it this way: it is the difference between cardboard and wood.

What is Luan?

The dictionary defines Luan as “the light yellow to reddish-brown or brown wood of any of various tropical southeast Asian trees (as of the genera Shorea and Parashorea) which sometimes enters commerce as Philippine mahogany.” Long story short: Luan is an essential component in sidewalls for Filon trailers.

For a Lamilux sidewall, we laminate it to Luan. It is not scorable. In other words, it is not bendable. It is 1/8 inch or quarter inch paneling with little grain. When you laminate sidewalls, the Luan turns rigid and is thus only good for sidewalls.

What is Unicore?

Every RV has got, what we like to call, a front profile point. The top of the front wall wraps to the roof. In terms of the front wall, we can laminate Lamilux 1000 and 4000 to Unicore, a cardboard-ish product that can be scored to make it bend to the contours of the your trailer’s profile and top wrap.

Unfortunately, Unicore is an inferior product when wet. The front skin becomes bubbled. The problem with Unicore is that it is a sponge, sucking in water. Any small water leak – a screw, rail or seal leaking – will wreck the cardboard-ish Unicore, turning it into mush. This is the delamination process.

Luan, on the other hand, does not act like a sponge. The wood holds its integrity.

How can Hemet Valley RV help?

The moral of this Filon story is that you should always monitor your coach and make sure it is sealed properly. For those who own Filon trailers, we suggest an annual sealing.

We will help you answer the following question: should I replace the damaged section?

The industry has not come up with a suitable replacement for Unicore. You just need to make sure everything is sealed properly. Luckily, at Hemet Valley RV we remanufacture these parts to your specifications, having replacement Unicore and delaminated skins. We have mastered the art of not only building these parts, but also shipping them to anywhere in the USA or Canada.


*Image courtesy of Steve