Source: 2025 Q4 Beartracks, Bob Barrows
I have made and installed lighter weight door skins and floor sheets. Instead of using aluminum, I used carbon fiber and Kevlar. For the floor, use Kevlar layup, to about the same thickness as the aluminum call out. For the door skins, use carbon fiber about .025 thick, 2-3 layers. Lay up by using a sheet of .032 aluminum, about 2” larger all around than the panel needed. Apply three coats of wax to the face. Apply epoxy resin, lay first layer of cloth on wet resin, then apply a little more resin. Apply the next layer of cloth and poke it with a stiff brush until the cloth is a little wet from the underlying resin. Scrape the extra resin off to the sides with a plastic Bondo spreader. These panels will be about 1/2 the weight of aluminum.
I use the West System resins, selecting the slower variant (206) if I’m going to be working in hot temperatures, or the faster variant (205) for colder temperatures. A good starting point for these materials is Aircraft Spruce Part Number 01-01665 for the Aramid (Kevlar), or Part Number 01-01232 for the carbon fiber.
The West Systems epoxies are sold in various kit combinations starting with Part Number 01-08100 through 01-08400, depending on the size of the can and the hardener type.




The photo below shows the Kevlar hinge on the mouse door. This is a scrap piece of the same material in the floorboards. I start with a rectangle, then bend it in a brake to about 90 degrees. This breaks the plastic resin but the Kevlar fibers remain. It has a natural spring-back action and is good use for what would otherwise be waste.