A lot of the kits you find the bulkheads are few and far between, my guess is cost the more bulkheads the more it cost to produce the kit.
A problem with bulkheads spaced far apart the planking will sit flat between the bulkheads and have no support. To fix this problem most bulkhead hulls are double planked or filler blocks are used.
For this model I am using filler blocks for two reasons one is to fill the space so the planking has a solid backing and second to line up the bulkheads.
Material I am using for filler blocks is called sigh board.
A high-density polyurethane signage foam has become the worldwide standard for versatile “green” outdoor sign board. Artist-and environmentally friendly, it clearly outperforms wood in 3-D signage and display manufacturing applications, such as theme park, mall, trade show and movie environments. The material’s ease of machining, uniform surface and infinite finish options support new realms of creativity and craftsmanship. Our polyurethane sign board is impermeable by water and moisture, and able to withstand extreme heat and cold. It does not warp or bow, and when coated, it will not rot or decompose, providing long-lasting durability.
before I use any foam product for filler I will test the foam and glue. I glued a scrap on top then glued foam to foam and foam to wood.
then break it apart to see how it holds
ok passed the test and good to go
Looking very close at sigh board you can see it is quite dense almost like the cedar pencil.
Another nice thing with sign board it can be cut very thin and still hold its shape and not chip or fall apart