doctorwayne's 2013 Get Off Your Duff Challenge - Part 2

[doctorwayne]

Time to update this, as I've finally made some progress. I built new floors from .060" sheet styrene, with a very basic centresill consisting of two lengths of Evergreen 1/8" channel, and a pair of longitudinal stringers of .040"x.060" strip styrene. The bolsters are from Tichy, as is the "K"-style brake gear. The queenposts are modified Roundhouse parts.
I used monofilament fishing line for the truss rods, stringing it as a single piece over all 8 queenposts, looping it across the car's floor to get it to each adjacent row. The Tichy/Grandt Line turnbuckles were added at the same time, and all the lines were fairly tight and laying on the underside of the floor when first strung. I then added the styrene stiffeners to the top side of the floors, two strips about .570" high, cut from .060" material, as shown. These were cemented in place with solvent cement (lacquer thinner) and allowed to dry for a day or two. The monofilament lines were then lifted from the floor and placed over the ends of the queenposts. After allowing a day or two for them to stretch a bit, the turnbuckles were centred and ca'd in place.
These photos should explain the arrangement:




After Matt drew my attention to the alpine-style roof line at the car ends, I decided to re-shape them to allow for a radial roof, and did so by simply aligning a part of the circumference of a can of contact cement on the cars' ends, tracing the arc with a scriber. After sanding the ends to the new shape, I cut pieces of .060" sheet styrene, matching that curve, to act as intermediate supports for the roof, then connected them with one another and the ends of the car with strips of the same material, which acts as a ridge support for the roof. Rather than attempt precise placement of these components, I reinforced all joints with short lengths of .060"x.060" strip, and then set these assemblies aside to dry while I worked on the roofs.
This photo pretty-much shows the set-up:




All four roofs were laid out on a sheet of .020" styrene, then .020"x.040" strips added to represent battens. Once the cement had dried, I wrapped the sheet around another container of the same diameter as the contact cement's can (it was too short) and added elastic bands to hold it tight against the container. The two files help the elastics to hold the sheet ends tight, too.



Next, I used a blow dryer to heat the assembly, then let it sit overnight, hopefully to lock itself in a suitable curve. While it was curved, it wasn't enough to ensure that the edges would make contact with the cars' eaves:



My next attempt was to wrap it around an object with a smaller diameter, and a length of 1.375" dowel seemed to do the trick:



Here are the four cars, roofs held in place with elastics while the joints hardened:



Here's the underside of the roof:



...and a view of the yet-to-be-finished-end:



...and a side view of one of the cars. I've removed all of the lettering and started some of the detailing:




The next task will be to add ice hatches and roofwalks, then the ends and sides can be detailed.

Wayne