New Curves

Today we set the blocks for the hatch ribs.  These ribs differ from the originals in significant ways.

The two outside hatch ribs have the same outer profile as the original sides and the same depth, but the ribs we created with the original design profile are already installed in the sides of the trailer (and therefore become "actuals.")  Thus, we need to create additional ribs that conform to those" actual" exterior curves (regardless of the design)

Whereas the original mould blocks were set up such that the interior profile was used as the guide, these blocks are set up to refer to the exterior profile as the design guide, since it is important that the hatch external profile match the trailer external profile.

The center rib profile is 3/8" inside the outer profile, while the original interior ribs were created 1/4" inside the original.  The 3/8" difference relates to the beadboard that will be installed in the hatch area per current design, where the outside will align with the existing perimeter.

Thus, we need to create two new ribs with the existing profile, and one new rib with a 3/8" offset from the existing curve.

Learning from our earlier experience, we decided to install a greater number of stations for the laminations. 

Since we are only interested in the hatch area, the overall curve is length limited appropriately.  

The next step is to laminate an external hatch rib. 

Note that the thin plywood strip attached to the protruding blocks is classified by OSHA as "A Worker Midriff Hemotoma Prevention and Ameloriation Device (AWMHPAD)."

In other words, it will help prevent inadvertent gut gouges that might be incurred while bending over the table (a condition to which your editor is most prone) or in casual passing.

Our fine government at work.