Rivarossi diesel horns and car replacement roofs

Over the holidays I obtained a damaged Rivarossi HO set and decided to design some replacement components. Specifically, replacement roofs for the passenger and RPO (Railway Post Office) cars as well as the fragile air horns on the diesel engine.

The set I obtained had the car roofs melted and the horns missing from the engine. You can see the photos below.

Each of these prints is quite simple with minimal support.

The air horns:

The horns are printed on a raft with only a few supports. I have included two different sizes for you to select from depending on your preference.  They are meant to be glued over top of the original broken off parts.  So, there is no need to drill or modify your original engine shell.

Passenger car replacement roof:

The original Rivarossi passenger car roof is a single piece of transparent plastic with the rooftop painted black.  It is held in place by multiple tabs under the car chassis.  If you push the tabs in, it will allow you to remove the roof. Once removed, you can install each of the passenger car roof pieces.  For mine, no glue was needed because of the snug fit.  If yours is the same, the easiest way to install the roof is to place each roof end in the car:

Then lower the center section down where both meet. This will form a nice snug fit.

RPO car replacement roof:

The RPO car replacement roof is installed the same way.  You may find that it is harder to remove the old RPO roof.  This is due to the old roof being held a bit tighter by each of the doors.  On my car, the roof melted almost as bad as the passenger cars.  You can see a side by side of old and new roof below.

When finished, the car has a much nicer look than with the melted roof.

I hope this design helps someone out.