I completed my Lionel 3-Rail to 2-Rail conversion using a different method than changing out the wheelsets. The reason for this method is I have several pairs of American Scale Models 100T Roller Bearing brass trucks that I wanted to use and these cars seemed like a good candidate. Little did I know how much work it was going to be but it was a fun project that kept me out of trouble .
I quickly realized that I had to overcome several issues. The first issue that I had to resolve was with these ASM trucks (and this would apply to pretty much every application of these trucks on any piece of rolling stock) is that these ASM trucks have a threaded bolster hole and come with a nice shoulder screw and coil spring. The issue is that this threaded bolster design pretty much requires the screw head to be on the inside of the rolling stock (akin to how MTH mounts their trucks) rather than the more conventional method of passing the screw through a hole in the truck and then threading it into the bolster on rolling stock. Obviously, could not mount the trucks with the truck mounting screw on the inside of this piece of rolling stock, maybe this truck mounting method would be more useful on something like a boxcar where you can easily hide the screw on the inside of the car. In addition, I wanted to reuse the ASM-provided shoulder screw and spring so that meant some modification of the truck was in order. The first item was to drill out the threaded hole to allow the shoulder to pass through it freely.
The next issue I encountered was with the screw itself, the head on the screw was too large to seat down in between the casting webs on the truck bolster so the head needed to be turned down a bit. A small collet chuck made short work of that
The next task was to address the bolster on the car itself. The existing Lionel truck mounting bolster needed to be completely redesigned for mounting these ASM trucks. For this I had to come up with a design that would handle the 3 MM shouldered screw and maintains the proper car height. I made a plastic prototype to test for coupler height and adequate truck clearance and came up with the following design, which I then modeled in 3D CAD so I could machine the part out of some brass bar stock.
One modification that I had to do to the existing Lionel bolster arrangement was to remove the existing plastic truck mounting boss from between the two bolster webs on bottom of car. I removed this center plastic truck mounting boss with an Xacto knife with a chisel style blade installed.
Next, I did the CAM for generating the G-code to CNC machine the part and used my CNC mill (only fitting that I used a mill on a mill gondola ) to machine up a new bolster out of brass bar stock.
I then painted it up and installed it on the gondola with some CA
I then mounted the trucks and put it into revenue service.
Now I just need to whip out a few more for the remaining gondolas that I have and think up of some cool loads to put in them.
Scott Kay
Austin, TX