Tuesday, November 1, 2011

From Mockup to Model: Beefy Highway Overpass Abutment

A model abutment . . .
. . . starting from this mockup
A couple of weeks ago, I made a mockup of a of the highway overpass at the west end of Dunes Junction. I liked how the mockup looked--its general dimensions and proportions seem to work, so I used it to begin work on an actual highway bridge model.

Bruce Petty showed how he built a highway overpass with styrene sheet and Rix Products highway overpass components in the September 2011 Model Railroader, and my model is drawing on Bruce's techniques.
.040" styrene sheet on the top and
 ends, .080" sheet on the outerwall

1/4" square styrene bracing--
stiff and strong. Grrr!
I did make some key changes to how Bruce built his abutment.  Bruce fabricated his abutments with .030" styrene and Plastruct structural shapes for bracing.  I opted to use heavier materials for extra strength and durability. The outer wall of my abutment is .080" styrene; the ends and top surface is .040" styrene.

To really add some beefy bulkiness to my abutment, I added bracing with 1/4" square styrene strip.  The abutment is quite solid and heavy as a result. This sucker will not warp or even flex.

Next steps: filling and finishing edges of the abutment and preparation for painting. Then the actual span and a support pier.  Stay tuned for more.