In preparation for the install of the diff, I took out the boot floor, which is a thin piece of ply. The bottom of the wood is visible from under the car, and so my thinking goes, exposed to the elements. As a result I decided to give it a bit of weatherproofing while I had it out.
I thought about varnish, but that seemed a little over the top, and Simon, a fellow builder, mentioned that on his previous Caterham, it had only got wet when he washed it.
Hunting about for the right solution, I decided to apply teak oil to the sheet. It won’t take ages to dry, won’t add to the thickness of the wood, and might just improve the appearance of it a little, as well as adding in waterproofing.
Three coats later, and it has indeed brought out the grain of the ply a little, though not as much as I had hoped. Water does bead on it though, so I’m happy.