1938 2.9 8C Alfa Romeo Le Mans Coupe.

 
 

Each of the boxes is first treated with a release agent then filled with a mixture of polyester resin and aluminium powder.  The first coat should contain as much aluminium powder as possible so that it will not run, and should be painted over the pattern and inside of the box.  Then glass cloth and more resin applied to partly fill the box, finally filling it with resin and sawdust to the top to make a solid resin block.