Upon return from our beachside camping last May, the trailer got a thorough rising off of salt deposits, and the awnings got their annual washing. I opened the awnings and flushed off large amounts of dirt and debris that especially like to accumulate where the fabric attaches to the trailer. I then followed the recommended method of washing the fabric as mentioned in my article, “Trailer awnings“.
I avoid getting onto the roof by using a step ladder and tools with an extended arm for both washing and waxing the trailer, including the roof.
This is also a time when I inspect for filiform corrosion and take appropriate protective and treatment measures. Protective measures include using good quality wash and wax materials. I particularly like Meguiar’s products, especially their Mirror Glaze Polymer Sealant #20, which I have applied every summer. Since using this sealant, the filiform growth found on the edges of some of my aluminum panels and rivets has been stopped in its tracks. The below photo of my “dragon” filiform corrosion was taken last month and shows no growth from its original photo taken in 2008.
Treatment measures that have worked well for me (with the exception of the taillight bezel housings) include Boeshield T-9 Rust and Corrosion Protection and CorrosionX. I also apply 303 Aerospace Protectant to rubber seals such as those around windows and the FanTastic Fan Vents (protects and keeps them from sticking). These products are currently available at the Airstream Store.
The taillight bezel housing fixtures presented a more difficult problem. Even with the treatments mentioned above, filiform growth continued unchecked until I stopped it last week, using more drastic measures. My guess is that the clear coat on these fixtures is thinner and more fragile, so when filiform starts to grow here, it appears to lift and break the clear coat, allowing the filiform to be nurtured with more air, moisture and salts. Filiform lesions on the taillight bezel that once looked like this in 2008, now looked like my mom having a bad hair day.
Up until now I have believed that it is best not to disturb clear coat finishes on the trailer, but these taillight housing filiform lesions needed to be excised. I adapted a method of filiform removal devised by a member of AirForums.com. Instead of a Dremel, I used a small screwdriver to gently scrape away the crumbly clear coat and filiform lesions. I then used wet sandpaper in incrementally finer grits from 320 to 600, along with mineral spirits, to smooth the lesions. (I eventually found even finer grit of 1000 to 1500 at a local auto parts store.) After cleaning once more with mineral spirits, I applied two coats of a good quality clear nail polish.
The “bad hair day” lesion is gone, only its ghost is seen, along with a few diagonal scratches from a Dremel tool, which I quickly stopped using. I cleaned up all of the other lesions on the taillight housings in the same manner.