4-4-0 Conversion Part 3

I have been asked to get on the ball and finish this conversion. My deepest apologies, I had sent the body off to be painted after I narrowed it and then the hard drive that the pictures were on crashed, so I haven't done anything with the conversion articles. Back to work on it then.

Now that the locomotive had been disassembled, it's time to narrow the body before it can be painted.

To do this you need a MicroTrains Z scale gauge, a set of calipers, a collection of #11 Xacto blades with handle and a Dremil tool with a sanding drum. I did my first one using only the MT wheel gauge without benefit of calipers, but the calipers do make this job a lot easier. I had to narrow a couple of sets of drivers for my first one because I melted the plastic on one set and destroyed the drivers, and on the second set I didn't chamfer the axle ends and destroyed the drivers trying to put them back on the axles.

To shrink the body down you squeeze the drivers in on their shafts until they fit the Z scale MicroTrains wheel gauge (or until they are .205" back to back). Be sure that the gear is centered between the drivers and then mark the ends, slide the drivers off and then cut the axle stubs off (you want to remove 0.050" from each axle end). Chamfer the axle ends to install the drivers back on and quarter the drivers (this is how I usually do it to prevent damage to the drivers). The axles will be 0.375" long when you are done.

It's easier to take the drives off and chamfer the axle ends when you are done, but pushing the drivers in and grinding/filing off the axle stubs does work. To do it this way I push the wheels in to fit the MT gauge, making sure the gear is centered between them, then mark the axles with a black magic marker. Push the wheels all the way in to the gear and cut the marked ends off of the axles. Work slowly and let the axle ends cool between cuts so you don't melt the driver centers. Quarter the drivers when you are done.

Next take a file and file the bottom plate, removing 0.050" from each side, to reduce it's width to 0.185". The rule of thumb is to file until half of the lettering is removed from each side. Now you can reinstall the worm gear and bottom plate into the loco shell and use it as a guide to narrow the locomotive wheel wells. Work slowly and carefully, you will open the tops of the wheel wells into the cavity where the worm gear resides but this is OK. A combination of #11 Xacto blades and the large sanding drum for the dremil tool works very well for this, but use a variable speed tool set to a low speed setting to prevent overheating and distorting the plastic shell. Remove the bottom plate and worm gear, install the narrowed drivers and make sure they turn freely. Remove material as necessary until they do.

For the pilot truck, cut the plastic bars that hold it to the cylinders at the ends of the slot the truck rides in, the front bar at the right side and the rear bar at the left side, to make two L shaped pieces. Pull one wheel from each axle to remove the axles from the truck, reinstall the wheel and squeeze the wheels to fit the MT gauge and cut off the stub ends. File each side of the pilot truck 0.050" to fit the narrowed axles. Reinstall the axles and wheels into the narrowed truck, making sure they turn freely.

Now to narrow the cylinders (this is optional but it does make the loco look better). Trim the bottom of each L back to the cylinders to narrow them (I really need to take some pictures of this step) and then glue the cylinders back together, installing the pilot truck as you do so. Cut the same amount off of each valve gear hanger on the locomotive body so the cylinders will fit back on. Paint the locomotive body and reinstall the cylinders and pilot truck. Don't worry about the mechanical strength of the cylinder connecting bars too much, the physical strength of the cylinders glued on to the locomotive body supply most of the needed support; the bars are there mostly just to hold the pilot truck. You can drill some holes and put in brass rods to replace the plastic if you like.

At this point the drivers, worm gear and bottom plate can be reinstalled. To reinstall the drive rods you will either have to trim the locomotive body between the drivers to clear them or bend them outward to clear the locomotive body. The locomotive body itself is now done.

In the next installment we will narrow the tender trucks and reassemble the tender. Then the tender can be reunited with the locomotive and the finished product can be tested.