Pennsylvania Railroad X43A AAR-design Welded Box Cars and Model Underframe

 

The Pennsy received 1,500 X43A welded box cars based upon the AAR design of the late 40s/early 50s (car nos. 602000-603499.) The "standard" design of the era primarily used riveting for construction, but these cars, built by American Car & Foundry, employed welding for the sides and underframe. Each side had 12 panels, compared to the typical 10 of most riveted cars. Other specialties included R+3/4 Improved Dreadnaught ends, Murphy diagonal panel roofs, postwar Youngstown corrugated steel doors, Ajax power hand brakes, Apex Tri-Lok running boards, and National C-1 50-ton trucks.

As delivered, the cars were painted in the familiar circle keystone scheme, with one highly unusual twist, at least by Pennsy standards: the roofs were painted/coated with black car cement. In mid-1954, the PRR briefly adopted the "Calendar" scheme, and at least one (and likely more) of the X43A class was repainted in this scheme, PRR 603116 shown above. 

By mid-1954 to the late 50s, the scheme was changed to the "shadow Keystone" scheme shown above, including its various nuances and iterations over the remainder of the 50s.

By the 60s, the "plain Keystone" scheme and its iterations were used until the Penn Central merger, as illustrated by PRR 602469. Note that there were other changes as well, including removal of the running boards, shortened ladders on the A end (and B end on some, if not all, cars) and strengthening of the side sill support and lower door post/side/side sill support junction, as shown above.

Some of the X43A class made it into the fleets of other roads. Western Maryland 461213 is an ex-PRR car with reinforced side sill support and lower door post/side/side sill support junction, albeit different than the PRR solution. Also note that the hand brake (and ladders) on the B end remained at the original high-mounted location.

B&O 463529 is another example of a secondhand X43A.

The kits for these can be found at the Speedwitch Models page. All versions of PRR lettering, Penn Central, Western Maryland, and Baltimore & Ohio are planned. The welded underframe features many of the nuances of the prototype, including the non-linear shape of the flanges of the crossbearers and crossties (if you look, you will notice that the flanges are not straight-edged, but rather wider and narrower at various points, as on the prototype,) the "perforated" bottom crossbearer cover plates (the perforations allowed the surfaces inside the "cutouts" to be welded, too, increasing the surface area of the welded surfaces,) Wright pipe hanger, the stringers that were riveted and welded on those closest to the center sills and welded only on the outer stringers, the accurate "teardrop" openings in the bolster cover plates, plus the bulb angle side sill supports and channel bolster tabs, shaped exactly as on the prototype. The brake arrangement also accurately replicates the prototype, down to the welded "grab iron" rod hangers and complex dead lever assembly.

There will be a follow-on post showing the finished model coming in the next week (or so.)

PFE R-40-25 Completed

 

I recently completed the final weathering and detailing on the PFE R-40-25 pilot model for the Speedwitch parts set [previous post linked here.] I am extremely pleased with the outcome. The details turned out almost exactly as I envisioned, particularly the hatch cover supports, the ladders, and the underframe. I doubt I will ever look at another car with Equipco hatch covers the same way again. It's fun to see the details "pop" under some weathering.

Regarding weathering, I used a variety of dilute washes, beginning with Tamiya Brown Panel Line Accent Color on the roof, panel lines on the sides, and overall on the ends and underframe. I added Tamiya black paint to the fan shaft detail on the car sides and then removed most of it with a cotton swab. I used mineral spirits to slightly dilute the panel line wash on the sides. I sealed everything with a flat coat and added washes of artists' oils, including a dilute grey mix overall and a few heavier light grey streaks on the sides, especially under the hatch areas, as well as on the ends to simulate spray from the wheels of adjacent cars. I applied another flat coat and then used Bragdon powders on the sides (a light grey) and PanPastel Paynes grey on the roof, ends, and underframe. 

The chalk marks are from National Scale Car

J-B Weld as a Filler

 

One of the things that has sometimes stymied me is the right filler for resin. Putty-type fillers like the old green Squadron stuff, 3M for auto body work, the tube fillers from Tamiya and the like, as well as the "liquid" fillers like Mr. Surfacer and Tamiya Surface Primer (which acts as a liquid putty directly from the jar) all flake off of resin because they are not able to bond with the surface like they can with styrene. I have used ACC/super glue as a filler in the past, but you have to sand it at just the right time... too soon and it can "ball up" and come off as you sand and too late and it is harder than the resin, meaning that the materials are removed at different rates by sandpaper, leading to surface defects of a different order, which is what you are trying to eliminate by filling and sanding.

I recently mixed up some of the J-B Weld (pictured above) to use as a bonding agent. It mixes like a two-part epoxy, where you stir equal amounts and then apply. While it worked for the bonding task, I also noticed that the dried leftover material (I mixed it in the underside of the bottle cap) was hard enough to sand, but not rock hard after 24 hours. When the right opportunity presented itself, I mixed up a little bit and applied some to a resin surface that needed a little touchup. It worked exactly as intended. It is now in the arsenal of filling and sanding solutions and is a good choice for resin.