Body Mounting Kadee 830’s onto an Aristo 40’ Boxcar
Moving beyond factory truck mounted couplers.
By: Keith Stratton

This installment is the second in a series of ‘How To’ articles about body mounting Kadee 830 or 930 straight shank couplers. To find out why I decided to go with body mounted Kadee couplers you can read my first article, which appeared in Issue #130 (November – December 2012).
For this article we are going to look at the ever-popular Aristo Craft 40’ boxcar. One thing to take note of is that the older versions had a high floor and a few years back they changed the molds. The current versions in production have a lowered floor that is at the correct height. So… how can you tell them apart?
There are a few differences but the most obvious ones for me are the roof catwalks and the bolsters underneath. The roof catwalks on the older/higher versions are solid, whereas on the newer/lower versions they are see-through (and much better looking!). Some people have replaced the solid catwalks with a see-through one so if you have obtained some used rolling stock you might not be aware if the previous owner had made this upgrade, however, it is most likely they did not.

Picture 1

Picture 2

That takes us to the underside. If you look at picture #1 you’ll notice the high bolster but more obviously the deeper longitudinal beams. In picture #2 you can see where these beams were cut down, the lower bolster plus the anti-rocking tabs on the bolster are shorter. Picture #1 shows one of my earlier installations.
The installation process for both floor height versions is identical; the only difference is the amount of shims to be used to obtain the correct coupler height. If you move the coupler gauge up to the end of the boxcar you’ll notice that the underside of the floor is above the flat of the coupler gauge. The shims are needed to bring the coupler draft gear box down to the correct height above the railheads. For the older/higher floor boxcars each coupler will need 4 x 1/16” shims and 1 x 1/32” shim to get the correct coupler height. For the newer/lower floor boxcars each coupler will need 1 x 1/16” shim and 1 x 1/32” shim to get the correct coupler height. The amount of shims may vary slightly, so it’s a good idea to have some extras around! This conversion is being done on one of the newer/lower floor models.

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You will see in Picture #3 some typical tools used for the conversion. A piece of track and one (or two) Kadee coupler height gauges, a #54 drill, a scribing tool, a chisel, a hobby knife with a #11 blade and a Phillips screwdriver. In my case I used a vertical milling machine to remove unnecessary tabs from the pocket area but this can be accomplished using a saw, knife or chisel just as effectively (and much more economically!!).
Now to the task at hand, converting an Aristo-Craft 40’ Boxcar (with metal wheels)! The first thing you need to do is remove the trucks and then cut off the mounting tab for the truck-mounted coupler. You can cut it off flush or leave a short stub similar to the opposite side. This can be seen in picture #11.

Picture 4

In picture #4 you can see the tab that needs to be removed from the coupler draft gear box pocket. It is only needed when using truck-mounted couplers to stabilize the coupler mounting arm. For our installation it sits right in the way of the rear screw of the draft gear box, so it’s gotta go!

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Picture 6

Picture #5 shows the car secured to the bed of the milling machine. I used strips of wood on either side of the catwalk o ensure it sat square on the bed. Picture #6 shows the milling cutter setup. The material cuts very easily and it takes no time at all to complete this step.

Picture 7

Picture 8

In Picture #7 the 1/16” shim has had the end trimmed off flush with the end of the car with the side mounting holes lined up with the center screw. This alignment will mount the coupler draft gear box as close to the end as possible, as the prototype coupler draft gear boxes protrude out from the end of the car. You will notice that a slot has been cut into the end of the shim to go around the protruding screw head. In hindsight, this could have been accomplished by drilling an oversized hole in the shim and not have the gap in the end. The protruding screw will need a few strokes with a file to get it flush with the top of the shim yet still be able to be removed with a Phillips screwdriver. Take the trimmed shim and line it up as shown. While holding the shim firmly in position, take a scribe and run it around the inside of both center holes. Remove the shim and then use the scribe to mark the center of each hole. Push and twist the scribe point into the center mark to create an indent for the drill. A #54 drill bit is used to drill the pilot holes for the mounting screws.
Picture #8 shows the screws being installed, and then backed out to trim the extruded / raised ring of plastic that forms around the hole. This raised edge must be cut, shaved or chiseled off otherwise the coupler draft gear box will not have a flush fit against the underside of the Boxcar floor mounting pad.

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Picture 10

Pictures # 9 & 10 show the coupler installed using three #4 x ¾” pan head Phillips screws. Due to the screw head shown in Picture #7, we are unable to use the center hole for mounting the box, which is my preference, so the two outside holes had to be used. If you run tight radius curves and need to cut off the side mounting holes that extend outwards on either side of the coupler draft gear box, then you should mount the coupler farther back so the end of the draft gear box is flush with the end of the boxcar. I usually paint the screw heads black so they blend in but have left them unpainted in the pictures so you can see them better.

Picture 11

Picture 12

Now it is time to put the trucks back on and check the coupler height against the Kadee height gauge, as shown in Pictures #11 & 12. This one lined up just right, but have a couple of 1/32” shims handy for final adjustments! Wow, yellow car, yellow height gauge, yellow test track… feeling mellow.
Well, now you are ready for the layout. I hope you have found this information helpful, even if you don’t run Kadee’s!!! Stay tuned for more articles on how to install these wonderful couplers on our 1/29th scale treasures… *