Monday, August 22, 2016

Lower Cowling Lined With Foil

During the down time while waiting for the upcoming airworthiness inspection, decided it would be a good idea to finish off the lower cowling by installing a self-adhesive protective foil covering that will help protect the fiberglass cowl from the heat of the exhaust pipes and muffler.

Van’s suggests marking the lower cowl adjacent to the location of where the exhaust pipes for the #1 & #2 cylinders pass nearby, then remove the lower cowling and make paper templates that cover the areas marked using a photo shown in the construction manual as reference for the placement of the foil. Once the paper templates are made, they are used to cut the foil to size. Prior to installing the foil, the areas being covered were cleaned with Acetone to help the foil stick better.

My foil was rolled up into such a tight tube that it created wrinkles in the foil that, by in large, were impossible to pull out … especially in the areas where there were compound curves. A Bondo spreader helped smooth some of the wrinkles out and work the foil down tight to the cowl. I wish Van’s would have left the foil flat ... but it is what it is.
Applying the first piece of foil onto the lower cowling.

After the foil is installed onto the cowling, the edges are to be coated with epoxy resin to help prevent them from pealing back over time. I ran out of time so did this in two steps … below is a photo showing the resin coating on the edges of the foil on the sides of the cowling. However, the edges of the foil on the bottom have not yet been coated with resin.
Installed protective foil coating on lower cowling. Note, the edges of the bottom piece of foil still need to be coated with resin to hold the edges down.