Boston & Maine Converted Baggage - Express car 3280 - Part 2

Selecting Core Parts

This model build is essentially a scratch-bash, applying scratchbuilt sides to a kit-bashed readily available core kit and roof from another.

The Branchline heavyweight coach kit was once again selected as the base core because the sides and roof of this kit are separate parts from the one piece molding of the undercarriage/floor and car ends making it much easier from the beginning to replace the sides and roof with one's needed to replicate the B&M car. The length of the chassis/floor molding from the Branchline kit can also be shortened quite easily for adapting to the shorter lengths of many headend cars.

The idea in selecting a roof for this build comes from Ryan Mendell who successfully used the venerable Athearn heavyweight coach round roof on his beautifully built Canadian National RPO. This roof is easy to obtain on the used market and will replicate the round roof of the B&M converted baggage-express car well. Two second hand Athearn coach bodies were obtained from The Hobby Gallery which is always a great source for used equipment and new offerings.

The Roof

The roof from the Athearn round roof coach needs to be removed from the one piece car body molding before it can be used for this build. Also the as molded roof of this coach is not long enough to model the B&M car and therefore needs to be lengthened, I decided to add length to both ends with equal sized pieces from a second Athearn car body.

After determining where to make the cuts to finish with a roof length equal to the prototype, both of the Athearn coach car bodies had a slot cut thru the roof at each end on a general use compound miter saw. The one being cut below will become the center portion of the finished roof.

The second roof had similar slots cut, the equal length end pieces below will be grafted to the center section resulting a correct prototypical length roof for the model.

For safety reasons cutting all the way thru the car bodies on the saw would require a firm interior support, not wanting to take the time necessary make a support equal to the interior width of the car body was the reason for cutting slots only thru the roof. After the slots were cut thru the roof the car ends were easily removed by finishing the cuts with a pair of side cutters. Both car sides were then removed from the remaining portion of the roof by scribing a line were the roof meets the sides, then snapping off the sides much like the scribe and snap method used when working with styrene.

Below is the finished prototypical length roof.

Undercarriage/Floor & Ends

The Branchline core undercarriage/floor is to long and will need to be shortened to the 75' 5 3/4" overall length of the prototype car.

One car end retains the as built vestibule of the original prototype C&O car, this end of the Branchline core will be left as originally molded. The opposite end of the prototype car has no vestibule, this end will be shortened between the bolster pad and the car end to achieve the correct prototype length.

For the correct placement and prototype distance between the truck centers the bolster pad on the end being shortened will be turned 180 degrees at the same time the end is being cut to length. The photo below compares the shortened car length and rotated bolster pad on the left to an as molded Branchline part on the right.

Extreme care must be taken when bonding these 3 pieces back together so the car floor and sides remain in alignment as they did with the factory molded part, to ensure proper alignment a straight edge clamped to both sides of the interior floor during the gluing process guaranteed a straight and level end result. 

The prototype car has a different non-vestibule car end design than the vestibule end, to model this other design the car end will be kitbashed to appear as the prototype. In preparation to correct this end the unnecessary molded parts of the shortened end section seen below were cut away before rebonding this end to the rotated bolster and core undercarriage/floor.

Below is the completed non-vestibule end of the core base of the model.

To ensure that the outer face of the car body end will remain plumb to the base undercarriage/floor styrene supports sandwiched between the interior vestibule wall and the car end were glued in place. For a good end result these supports should be precise and were made to a +/- .005" tolerance. These supports will not be seen after the end door is in place.

Also note the sturdy styrene strips glued in place on both sides to reinforce the glue joints of the 3 now connected pieces of the core, these strips permanently take the place of the straight edges that were clamped on for proper alignment during the glue curing process.

One more modification is needed to complete the two core pieces. The Athearn roof ends must be arched to coincide with the arch at the top of the car body ends. The below photo shows this arch has be cut into the roof end, still much sanding left to finish this end for painting but that will come later in the final stages of the build.

Next post will build the car sides and non-vestibule car end.