There is four partial bulkheads in the saloon. They constitute the fore and aft part of stowage space. There I will store food batteries and other things that do not like water. Above this storage is the main hatch therefore it is essential that the lid is waterproof. To achieve that there is a gasket in the lid but it is equally important that the top edges of the bulkhead that will take the lid is as parallel. My method is to use a piece of plane particle board  (particle board do not warp) and to screw on L-profiles in the corners and clamp it. First I got the aft bulkhead in place then making my arms small I was able with the help of wedges and other tricks to get the forward bulkhead tight to the particle board. Then I fixed it with NM-epoxy. The obtained result was very satisfying. Below is two pictures.

Below the template in action.

To be continued…

Regards Yrvind.