While I think I know the two prototypes I am going to base the cars on, for right now it is just important to start building. I printed out the slides and wrote down all the sizes of styrene I needed. After consulting with my stash, I realized I needed a lot more so off to the hobby store I went. I swore years ago I would never turn into the kind of guy who hoarded hundreds of sizes of tiny little white strips of plastic. Oh, how things have changed. I am starting to outgrow my "shelving system" and will soon need to build more of come up with a system that holds more.
Using my Northwest Short Line Chopper, a fresh Xacto #11 blade, and an old chisel blade that I rarely buy replacements for (I should, though), I started construction on a Saturday afternoon. The only real difficulty I encountered was keeping track of the fact that every quantity had to be doubled because I was doing two cars. In preparation for the project, I had purchased an HO scale ruler (another thing I thought I would never need) though I only got a cheap one for $3 on Ebay. I like clear rulers more than metal ones, because it is easier to see the stock. Little dots were marked on the lower edges to indicate where the beams would be shaped.
Then, portions of the ends of each beam were laid out and cut away. It was a bit tedious but not too much so, and as long as I was close it was okay. No one is really going to be holding up a ruler to the underside of my car to ensure that all are identical. That being said, I found it much easier to use the chisel blade to chop along the cut lines instead of trying to line up a metal ruler along the lines and score with a #11 blade. Personal preference, I suppose. The cut lines were cleaned up with some emery boards I bought at the supermarket. The two inner beams on each car had to be notched for the coupler pockets which will come later.
The bottom edge of the four longitudinal beams have a small piece of styrene glued on the bottom to form a flange cap. Sort of like an L-girder. While there must be easier ways to do this, I did it one edge at a time. First, I glued an oversize piece to the middle of the beam and held it in line with my metal square (which is a really useful tool for all types of model construction). Then I moved onto the next beam, and by the time I was done with that the MEK was cured from the first one. Then, I worked on the diagonal piece, and to keep it firmly engaged with the main brace I wedged it between the square and another pieces of straight aluminum stock I keep in my workbench for occasions like this. Since each beam had two ends, this process was repeated 16 times. Finally, the remaining short edge was done. After everything had cured fully for a bit, I trimmed the flange to final size.
Next, the two inner beams were glued together with a spacer piece of styrene that ran the hole length. After that cured, another piece was glued over the top to make sort of a cap. Side note: all of this is explained in great detail with pictures on the web link I referenced, and I am probably not using the proper terms. Then, some C-channel was notched for the couplers and glued to the ends of the center beams. It is important that these channels be perpendicular to the center beams but there really isn't an easy way to check that with a square. So, I built it on graph paper... one of my useful tricks.
Next, the two side beams were glued to the end channels and again I used graph paper to ensure that everything was square. The side beams were super flimsy at this point so it had to be handled delicately. Finally, eight pieces of cross bracing (bridge beams) were cut out and carefully filed along one edge per the plans and then glued between the sides and the main beams. There was absolutely no way a square would fit in the frame so I taped the frame to graph paper to prevent it from shifting and then glued each brace in, one at a time. I had to hold it in position with pliers and drop in the MEK. It was very Fiddly.
But, at the end of the the first weekend I had two car frames. As my last step for the night, I tried to use some Testors Putty to hide any gaps or scratches, but I used the wrong filler. After a time of sanding, scraping, and prayer, I think I managed to salvage them. The next weekend, I began adding some longitudinal braces, which in this case were Plastruct L-angle. I had to notch the car frames to fit these pieces and at first I tried a razor blade (too fiddly), an Xacto knife (too slow), and a small square file (just plain annoying). But, my motor tool did the notching in seconds, and once the plastic cooled any slag was easily removed.
I don't particular enjoy working with ABS plastic because it doesn't bond as easily as styrene. I started with MEK but the parts kept popping of the slots. They are thin and delicate and not perfectly straight, so adjusting one led to another moving. Even with superglue, I still had problems. I really need to buy that accelerator that I read about. Once all the pieces were in the frames, I weighted them down with the close pins and let it sit overnight. The braces still need to be trimmed to length but I will do that later as even looking at them the wrong way would likely cause them to come unseated.
The car deck was next. While the finished car will have wooden deck boards on top, you still need to add a steel underframe to it. I drew out the floors per the plans and laid them next to each out (with a loop of blue painters tape underneath to keep them from moving) and used my scale ruler to lay out the stake pocket locations. Those are the dark areas on the sides that will eventually get cut away. If you think the lines got confusing, you would be right. I used orange marker first and then blue to figure it all out. Watching TV during the process didn't help. But, these sides will be face down and no one will ever see my mess of a layout job.
One thing that concerns me is that later in the process I am going to have to cut holes and slots for the brake piping and hardware to go through. The plans just cavalierly say to cut the slots. I don't believe the frame was strong enough before adding the deck to cut slots (it would break), but it sure will be hard to cut them afterwords. I guess we shall see. I had to add more cross braces which involve maneuvering tiny pieces of styrene into the frame and then gluing them with MEK. I cannot even imaging the dexterity and eyesight required for an N scale car. Finally, bolster locations were built up for the trucks to eventually mount to.Three weekends of work at a relaxed pace and I have two car frames nearly ready for final detailing.
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