I pulled the front Fantastic Vent and TV antenna. The vent had the foam gasket which was compressed and not doing much. Someone had smeared some caulk on the surface of the trailer, vent and antenna, but the seal had failed in multiple places due to flexing of the skin.
I scraped and then cleaned the roof with Toluene to get off the old sealants. I cut away the sealant that had flowed through the multiple sets of holes to give a flat surface on the underside of the skin. I made backing plates out of 1/8" x 1" x 1" angle aluminum and match-drilled them to the vent flange. I then mounted them to the roof skin with two screws each.
Next step was foam. I used two cans of red label "Great Stuff" foam, one on 3 sides of the vent, the other on the remaining side and the antenna. Prior to foaming i pushed several inches of 1/2" plastic tubing onto the TV coax and fan wires in hopes of keeping the foam from sticking to them. I also wrapped a 1" PVC coupling with wax paper and pushed it into the antenna crank hole to keep it clear and minimize drips to the inside, and masked from the top of the inner skin to keep any foam from getting on the ceiling and put a drop cloth over the recliners.
The foam has now mostly cured, and will hold the backing plates in place when i pull the screws to mount the vent. I am impressed with the additional rigidity on the inside. I can't check the outside because it started raining at 2PM when I finished foaming and hasn't stopped yet. If the roof is anything like the ceiling, there should be no more oil canning around the vent or the TV antenna. If it stops raining tonight I'll mount the vent and antenna in the morning. I may make it to Alumalina yet!
"You cannot reason someone out of a position they have not been reasoned into"
Al, K5TAN and Missy, N4RGO
2002 Classic 30 Slideout
2001 Safari 25 RB Twin (Gone, but not forgotten)
2013 Dodge 2500 Laramie 4x4 Megacab Cummins
WBCCI 1322, TAC FL-39, AIR 82265