Atlas 2-Rail O Scale Freight Truck Upgrade Kit New Bolster Replacement. PN# 20001 $11.95

REF: Item #7065 70-Ton Roller Bearing & Item #7066 100-Ton Roller Bearing

Sale includes 2 Main Replacement Bolsters (Poly Carbonate Blend) with 6 escutcheon pins (Inserts & To Be Trimmed) for spring positions, 2 top body bolsters (PLA) and 2 bottom body bolsters (PLA), enough to upgrade 1 pairs of trucks.

In the process of restoring older freight car models or scratch building new models, there comes a time when one must consider the trucks to be used. And one of the problems sometimes is getting the perfect pair of trucks mounted such that the car body is not to high or to low and that your coupler height comes in right on the money above the rails. The Atlas trucks for modern freight cars and rolling stock are reasonably priced, they look pretty good, and are operationally a smooth truck assembly. The only trouble I consistently run into is the fact that more often than not, they mount the body to high on the rails. The reason for this is the trucks are designed to mount on the underframe of an Atlas model. What is the difference? The difference on most detailed models, the underbody main beam is usually integrated with the body bolster structure. And, if the Atlas truck mounts on that body bolster, it is high because the top of the Atlas truck assembly has a cross member that is actually in my opinion the upside down profile of a body bolster. Whereby, the main beam on an Atlas model underbody is just short of where you would expect the body bolster to be. At least this has been some of my observations. So the truck mounts at the immediate end of the beam to the car body floor and levels to the correct height for the Atlas model design.

In order to have almost complete flexibility in utilizing this truck assembly, I worked up this kit for my own modeling purposes to first primarily give me a range of adjustment for getting the car body height correct on the rails and maintain operational clearances. Second, optionally one can add the brake beam detail but for the most part is not required. The kit does not require an entire disassembly of the truck. Remove the 2 flat head screws and take off the top cross member. See (https://johnwubbel.com/crh/Brass-Investments-Project-Legacy-YouTube-Videos/Atlas+Freight+Truck+Upgrade.mp4) Note the bolster cylinder is exposed, replace the Atlas top cross member with the supplied part reusing the 2 screws and note that you have the potential to grind off the top of the cylinder if you do not use the replacement part enclosed with this kit and gain almost 2.5mm that will lower the car body while still being able to mount the truck on a car that has the body bolster. For added stability and detail, snap in the under truck body bolster frame before mounting the truck to the car. Note that if you grind the metal from the top of the cylinder, put a heat sink on it so as to not deform the plastic brake shoes that came with the truck.

This requires a partial disassembly of the Atlas truck with 1 side frame removed. Some clean up of parts maybe necessary from the build plate or for fitting since these are made to very close tolerances. Once reassembled, the truck should not have any twist. It should sit flat on the track and roll freely. If the truck does not sit flat on the rails, it means a slight filing maybe necessary to relieve the over tight fitness of the parts.

Parts for 1 pair of trucks in this kit are printed with PC Blend & PLA filament sold as is straight off the Prusa Printer built plate, all sales final no returns. PLA is not dishwasher safe and may deform in a hot automobile in the summer time as it has a relatively low glass-transition temperature.

Kit Made In The USA.