The lid is made form bamboo lumber that matches the grain of the deck. No bent aluminum here, friends. It is reinforced with plexiglass to keep it from splitting and backed with cork to help it sit nicely and resist moisture. These layers are all bonded with the same epoxy that I used on the board.
The CNC cuts the lid out and removes some material to help with the shaping step. I use a 6.25/30 degree double-bevel along the edge. The bevel makes it easier to fit and remove the lid.
The lid is then bolted in place and contoured to the concavity of the deck. I use a grinder and orbital sander to get the job done.
It took me a while to get this lid just right. First, I tried just bamboo. It split on some of the test decks, so I reinforced it with plexiglass. I thought about using neoprene for the seal, but the cork mills really cleanly and looks nice. On the initial test decks that I made the lids would stick and not come out. The bevel helped, but when the compartment is bored out the deck “tacos” in the middle by about 1mm. This makes the opening slightly hour-glass shaped. I was able to compensate for this in the CAM software. Now the lid is slightly hour-glass shaped as well. The lid is a pain in the ass, but now it’s right.
The bottom and top have now been reinforced and I have a lid. Paint and grip is next.