Aristo streamliners

lowering & body mounting

Kadee 907 centerset couplers


Aristo Streamliners - Lowering & Body Mounting Kadee 907 Centerset Couplers
Ted Doskaris
January 27, 2015
Rev. GE-A

February 6, 2015
Rev. GE-B
Added Appendix A - Car Light Wiring

May 17, 2015
Rev. GE-C
Added Appendix B - Aristo Smoothside Car, Lowering & Body Mounting Kadee 906 couplers

Added Appendix C - Comparison of Aristo Streamliner, Smoothside & USAT Passenger Cars


October 28, 2016

Rev. GE-C1 Fixed / Repaired links

November 17, 2016

Rev. GE-C2 Fixed Stale YouTube Video Links


June 15, 2023
Rev. GE-D Added streamliner observation car "CamPac" 3-D print end plug choice with mounting pad applicable to lowered car for Kadee 907 coupler assembly


Comment about Aristo's Streamliners & Smoothsides
Concerns with Respect to Prototypes
Compromises - Mitigating Appearances
Observations About Prototype Loco and Car Heights
Car Lowering Methods
My Chosen Method
Factory Bolster
Bolster Types for Fabrication
Bolster Types Detail
Pivot & Guide Standoff Posts
Truck & Factory Bolster Removal / Wiring
Fabricated Bolster Installation
Optional Light Switch
Fuel Tank Removal
Truck Installation
Body Mounting Kadee 907 center set couplers
Observation Car End - Coupler Mounting

Appendix A - Example Car Lighting Control Methods

Appendix B - Smoothside Car Lowering & Body Mount Kadee 906 couplers

Appendix C - Comparison, Aristo Streamliner, Smoothside & USA Trains Streamliner


The Streamliners by Aristo-Craft (later successor company and also now defunct, Polk's GeneratioNeXt) have been around for many years having some factory evolutionary improvements over that time; however, some folks have done further things to improve their appearances or performance.

This article describes and illustrates what I have done in the way of adding body mount couplers in conjunction with lowering the cars that can operate on as little as 8 foot diameter track.
An example train having all body mount Kadee ceterset couplers used for testing is shown below.

For information about the E8 & Kadee couplers as to what I have done, see article,
"Custom Made Coupler Boxes & Kadee Centerset Couplers for Selected Aristo-Craft Locos",
 particularly the section,
"The Aristo EMD E8 / E9 Passenger Loco Application - Appendix D"


If you just wish to lower the cars but keep the original factory truck mounted knuckle couplers, you can skip the information provided about adding the Kadee body mount couplers.  If keeping Aristo Knuckle couplers, there is information about the E8 & Aristo's knuckle couplers in article,
"Aristo E8 front coupler modification Vignette"


I had accumulated seven new Aristo Union Pacific Streamliner cars over a period of time many years ago but never took an interest in them until now.  That's mainly because of three reasons:

1 Figuring out what I wanted to do (and how) to mitigate the awkward appearance of the streamliners

2 Awaiting the then subsequent arrival of the Aristo E8 Passenger engine that would make for an appropriate Union Pacific "City of ...." train that typically used EMD E units

3 Waiting until I retrofitting most of my rolling stock and engines, including E8s, with Kadee couplers (virtually all centerset types) with the intension of doing passenger cars last

Since reasons 2 & 3 have pretty much been addressed with some exceptions, it's now time to remedy reason 1.

Comment about Aristo's Streamliners & Smoothsides:

In the parlance of Aristo speak, they make / made two types of streamliner cars, the first being called the "Streamliner", which is characterized by fluted sides and ribbed roof tops, whilst the second being called the "Smoothside".  The car bodies of both types are made of mostly of aluminum.  However, they differ (aside from what their name obviously identifies) in length with the Smoothsides being longer by 4 to 5 inches.  Though both type cars share close similarities in the way of construction, the longer Smoothsides do necessitate some differences in modifications if equipped with  body mount couplers compared to the Streamliners that are described in this article.  See Appendix B for the "Smoothside" passenger cars.

The Aristo Streamliner cars are replicated after prototype Budd cars having stainless steel fluted sides and ribbed roof tops that are about 85 feet long.  However, Union Pacific's Budd cars were relatively few in numbers for them (about 50) and most were painted in UP's armour yellow & harbor mist gray.  

Concerns with Respect to Prototypes:

For me, there are 3 main areas of concern with respect to the Aristo cars verses the prototypes:

1 They scale out to be too short by about 20 prototypical feet (that's a bunch!)

For example, most modern type passenger cars are longer than a 60 foot box car, but as shown in the below example the Aristo Streamliner is virtually the same length of that box car. (Note that the Streamliner car was lowered by me and equipped with Kadee 907 centerset couplers to be more realistic.)


2 They scale out to be too high from the rail head by about 1.5 prototypical feet (this makes it noticeably taller than the E8 when, if anything, they should be slightly lower)  See below picture


Shown below is how a more realistic lowered car and factory car look next to each other at a distance of 10 feet.

3 They have truck mounted couplers that project out an excessive amount, particularly for early production runs, with the observation car end being grotesque (Maybe this was done to accommodate operation on a 5 foot diameter track circle to put around the Christmas tree.)

Shown below is an early example observation car.

Shown below is a rear view before and after modification comparison.



Shown below is the distance between two out-of-the-box factory streamliner cars.
- That distance is big enough to drive a Buick through! -

Now compare the dramatic decrease in distance (about 2 inches shorter!) with the body mounted Kadee 907 centerset couplers of the cars shown below, and these cars will operate on 8 foot diameter track;  that's why the slight gap between diaphragms is accepted.



Compromises - Mitigating Appearances:

I think the Aristo Streamliner cars are reasonably nice, so the intent is to mitigate their appearance to be plausible  (as shown above) whilst fitting body mount Kadee centerset couplers;  thus, lowering the cars becomes a necessity.  Even though the cars are shorter than prototypical, they will then look realistic enough to use, particularly, on a layout that is restricted in size and limited to 8 - 10 foot diameter curves that may preclude operating longer cars.


Observations About Prototype Loco and Car Heights:

A prototype EMD E8 or E9 locomotive dimensioned from the rail head to the top of the unit is 13 feet, 11 inches according to one source found for an E9 version (dimensions virtually the same as an E8).

For a 1/29 scaled E unit, the height from the rail head would be 5.76 inches.

An example Aristo E8 height from the rail head measured 5.825 inch which is 0.065 inch taller than the prototype.  This Aristo E unit has factory wheels that would scale close to 40 inches in diameter for a prototype, whereas, the prototype E unit actually had 36 inch wheels.  If the Aristo E unit were equipped with scaled 36 inch wheels, its scaled height would be virtually the same as the prototype.

A prototype Budd car as dimensioned from the rail head to the top of the car is 13 feet, 6 1/4 inches according to one source found for a blunt end version.

The car width is the same as the E unit at 9 feet, 10 inches.

For a 1/29 scaled Budd car, the height from the rail head would be  5.595 inches.  (Note that a scaled down prototype car when compared to a scaled down prototype E unit would then be lower by 0.164 inch.)  

The measurement I made on an example Aristo streamliner baggage car is 6.25 inches from the rail head, which means this car would have to be lowered by a whopping 0.655 inch!

If one were to achieve this amount of  prototypically scaled lowering (0.655 inch), repositioning the floor within the car body would be necessary, but to a greater extent with more complexity than done by the examples (described later) that I am aware of.  Moreover, lowering the car this much does not seem to be practical since the trucks would be excessively shrouded by the car's skirting by approximately a 1/4 inch, resulting in too limited truck rotation for operation on curves such as 8 foot in diameter and likely greater.

Car Lowering Methods:

Since these cars have been around for a long time, other folks found ways to lower them some time ago.  There are a couple of notable ways to lower them and a third way that could be a combination of methods.

Method 1:

Reposition the car floor within the body.

This is a very clever method done successfully by folks like Jim Carter and Mark Scyphers and probably others.  (However, this method may not be appropriate to new production run cars with interior seats since the seats would rise up into the windows that are now clear rather than translucent green.)

One or both plastic end bulkheads must be temporarily removed from the car.  
The underside of the bulkhead is attached to the metal floor by screwed -in sheet metal tangs.

Hidden inside the car, the top of the bulkhead is held in place by what appears to be a bead of hot glue of varying amount in both length and thickness.  (A plastic bulkhead held in place with much factory glue can be difficult to remove.)

With an end bulkhead removed, the metal car floor is disposed for removal.  (The floor my need to be "coaxed out" with a mallet; thus, it may require both end bulkheads be removed.  An observation car is more complex if removing the round end of the car.)

The floor is removed with air tanks, equipment box and trucks still attached - very behooving .  (For cars that have lights, the lights must be removed from the ceiling of the car whilst removing the floor.  Maybe cutting and later reattaching wires could be done as an alternative if need be.)  

Car Floor Reposition Info., Before & After:


The floor is extracting from its original "C" channels running the length of the sides within the car. (When the floor is factory installed in the "C" channels, the channels appear to prevent the sides of the car from bulging out should there be such a tendency.)
picture of extracting the floor apparently supplied by Mark Scyphers is shown on Geroge Schreyer's Web site.


The floor is reinserting into a new position more toward the roof of the car.
picture of reinserting the floor apparently supplied by Mark Scyphers is shown on Geroge Schreyer's Web site.
(With the floor repositioned here, there seems to be nothing to prevent the sides of the car from bulging out should there be such a tendency.)

The baggage car having two side doors somewhat to the middle on each side of the car appears to require bending of the floor's lips and maybe adding side shims as can be seen in Jim Carter's picture.
(The dining car having a small side door may have a similar issue, though probably simpler to deal with.)
That said, repositioning the floor is said to lower the car by about 3/8 inch (0.375 inch)

A couple of pictures by Jim Carter shows a before and after comparison of this method of lowered cars.
One of  Jim Carter' picture is a side view comparison.
Another picture of  Jim Carter's is an end view comparison.

Securing the repositioned floor:

In the original factory configuration, at each end of the car, there are 2 small sheet metal tangs held with screws for attaching the metal floor to the plastic bulkheads.
Once the floor is repositioned, tightening the screws  at the plastic bulkhead (albeit replaced with longer sheet metal screws) will now serve to tension the tangs in order to seat the floor against its new location.  (Pushing hard down on the car would appear to stress the screw connections - though maybe not a problem with reasonable handling.)
The middle of the floor is prevented from rising up by the name plate mounting pins (Tabs) that penetrate into and past the side of the car body.

(The baggage car does not have name plates, so the Tab support shown above would not be there.)

Method 2:

Replace the bolster with a shallower one (Like George Schreyer's cast resin bolster as described in his Web site or fabricate your own)

Method 3:

Maybe combine / adapt both methods 1 & 2 to achieve prototypical car height.  However, if prototypical car height is done the trucks' frames will tuck under car's skirt edge, restricting operation on only the widest diameter track curves.

My Chosen Method:

Since I already had acquired George Schreyer's bolsters a long time ago, albeit not enough, I decided to do Method 2 and fabricate additional replacement bolsters, but of my own design, since his are no longer available.

By incorporating "Roller Dowels" at the truck fulcrum, the design includes allowance for more friction free movement, including a bit more vertical forward / aft truck rocking distance.  This should improve operational performance on less than perfect track work.


Utilizing the fabricated bolster, a car height comparison is shown below


The bolsters I fabricated lower the car a bit more than George Schreyer's bolsters (respectively 0.29 inch as George stated vs. 0.355 inch) but not as much as repositioning the floor (respectively a claimed 0.375 inch vs. 0.355 inch).



The bolsters I fabricated allow car operation on 8 foot diameter curves, and that's with body mounted Kadee 907 centerset couplers.  The train below is shown on an 8 foot diameter track circle with E8 pulling lowered baggage and lowered observation cars all having body mounted Kedee centerset couplers.  The train operates OK in both forward and backup directions.



The observation car, also, has a body mounted Kadee 907 centerset coupler installed on the round end that includes a plug /spacer to cover the gaping opening formerly needed for  the truck mount coupler.  Because of this, this car, also, having interior lights took the most effort to modify, compared to the Baggage car having no lights that took the least effort.


Shown below is the E8 coupled to the end of the observation car.  The train operates OK in both forward and backup directions.


Shown below are a few close up pictures of the car/s body mounted coupler alignment with the Kadee 980 track and coupler height gauge on straight track.




- and how the cars look coupled together:





Factory Bolster:

Aside from being too tall, the Aristo factory bolster limits truck rocking distance to one side, which would seem to be rather intolerant to poorer track work, particularly having noticed the stiff springs in the truck.  Accordingly, you will notice an asymmetrical excursion if you push the attached car truck at each of its ends toward the floor of the car.



Though the height of the pivot post and fulcrum surfaces look the same in the above picture, measurements of an example showed the pivot post to be about 0.030 inch lower.  This provides some small amount of left side rocking distance, but when testing this with the truck mounted, you can be misled thinking it's greater depending on how loose the screws are that hold the truck in place.

In contrast, the fabricated bolsters with roller dowels allow a more symmetrical amount of rocking excursion on both sides of the fulcrum.  When the truck is rotated, the dowels typically do not roll too much in the slots with one reason being the truck rotation radius is located at the pivot post not at the rocking fulcrum, but the dowels' rounded contact surface still offers reduced friction.

Bolster Types for Fabrication:

There are 3 possible types of bolsters that can be fabricated: "Winged", "Full" and "Basic".  Each type is made from 3.7 inch wide by 1/8 inch thick plastic that can be inexpensively purchased and cut in sheet lengths from TAP plastics.  From these sheets several bolsters can be cut off and scribed where holes and cuts are to be located.


Each bolster type has two slots to accommodate fulcrum "Roller Dowels"; spacer standoffs are later added for pivot & guide posts.


An example Basic Bolster is shown below:

As to the dowels, TAP Plastics sells lengths of 3/16 inch diameter round stock that can be cut into segments for the dowels.  Alternatively, individual 1 inch long Nylon spacers of the same diameter can be purchased from a hardware store.

The bolster material I purchased from TAP Plastics has peel-off paper on each surface, so I took advantage of this by outlining with pencil where holes and cuts are to be located.  The Winged bolster penciled outline is shown below.


This material happens to have a glossy side and opposite the textured side.  The textured side is best exposed if it is to be painted.




Bolster Types Detail:

Each bolster type is 1/8 inch thick plastic.

Each bolster type is 3.7 inch wide so when installed it just fits where the car floor meets the car sides.

Drawings will be shown for the bolster types that specify hole sizes for screws.
Note:  In the event holes are discovered to be stripped out in the car floor during installation, in most cases the screw size can be increased by one (e.g.  go from #2-56 to a #4-40, or go from #4-40 to #6-32)

1) The "Winged" type:

This has a 4 point mount with "U" area cutout for electrical cable clearance.  The Winged type can be used on all streamliner car types, though more involved to fabricate.  (It may be more practical to replicate this type by cloning, like on a 3-D printer.)  As to pivot and guide post fastening, a stud method can be employed.

The Full and Wing type bolsters are the same except the area cutout shown in yellow below applies to the Wing type.



Shown below are example techniques used when fabricating the Winged - also, applicable to the Full type



2) The "Full" type:

This is a full bodied bolster with 4 point mount that does not need electrical cable clearance.  Thus, the cutout shown in the drawing is not to be done since it's not needed; therefore, it's simpler to make for use on the streamliner baggage car that does not have interior lighting.  Shown below is an example being incorporated on a baggage car - though the  stud method for pivot and guide post fastening is not exemplified here.


3) The "Basic" type:

This is a truncated variation using less material having a 2 point location mount and is the simplest to make.  As such it's preferred and can be used on all streamliner car types.  However, this type necessitates drilling & tapping two additional holes in the car body floor for securing the pivot and guide standoff posts - though it's desirable to do same for the other types, which is what I have done.


3a) Basic Type, Variation with ball bearings:

A variation of the basic type is the substitution of ball bearings in place of roller dowels.

This is the best choice of all bolsters since it's the easiest to make and affords the most friction free performance since the truck body contact area is working against individual ball bearings at different radial distances as it is rotated.  However, obtaining 6 ball bearings 3/16 inch diameter for each bolster will be required.

BasicReplacementBolsterWithBBholesOutlineDimensions IMG 4076

Shown below is where 3/16 inch diameter nylon ball bearings can be obtain from US Plastics at a reasonable price.  It's best to buy in quantity to make the shipping cost worthwhile.  I purchased 100 for about $10.00 U.S.

USplasticsBallBearingComposite IMG 4082



Shown below are example techniques (essentially same as Winged type) used when fabricating the Basic type



Pivot & Guide Standoff Posts:

These are needed for mounting the truck.  They are used in concert with all fabricated bolsters types.

Standoff spacers measuring close to 1/4 inch long by 1/4 inch in diameter (slightly undersized preferred) can be purchased at a hardware store or maybe from TAP Plastics then cut as required; however, shown below is a convenient way to utilize bushings salvaged from an Aristo Bettendorf freight truck that you may already have.

With the truck's side frame removed, the bushing can be extracted as shown below.


 I believe these bushings are made of Delrin which is ideal for the application:



Truck & Factory Bolster Removal / Wiring:

This must be done first so the new fabricated bolster can be installed in its place.

Wiring is prevalent for lights on all but the baggage car.  First unfasten the truck.  


The truck can be set nearby with any wires still attached.


For each truck, there is 1 wire that has a lug and is fastened to the metal floor that can be unscrewed.  The other wire that is captive to the factory bolster can be removed by cutting a slot in the bolster body so it can be slipped out; otherwise the wire will have to be cut and then reattached (soldered) and insulated.  If you are willing to cut the wire, it may be advantageous to install an on / off switch to control the car lights.  I did this.  (This option, that includes adding a single pin connector, will be discussed later.)   Now remove the 4 corner screws that hold the original factory bolster.  Sometimes the little screws that hold the bolster maybe hard to remove.  If so, use a small reverse drill, and they can be made to back out in an instant.  I had to do this a few times.


If installing Kadee body mount couplers, the truck will have to be removed so its coupler tang can be cut off - otherwise it will  interfere with the coupler box, in which case the wire captive to it must be cut.  Kadee coupler installation will be discussed later.

Fabricated Bolster Installation:


When body mounting Kadee couplers (discussed later), it's easier to do this first, then install the bolsters, etc. since more space is available to work with.

When pivot and guide post are fastened to both the bolster and floor, the only need for the bolster corner mounting points is for accurate location.  Accordingly, the fabricated bolster, also, serves as a template for drilling and tapping the pivot and guide post holes - installation illustrated below.



Demonstrated in more detail below is the same type bolster installation being done on a Winged type.


If choosing stud method for attaching pivot and guide posts, only use Winged and Full type bolsters that have 4 corner mounting.  Moreover, the Winged type bolster with studs may best suit the newer streamliner cars that have interior seats since drilling through the floor might damage them or cut hidden wires close to the floor since these cars now incorporate electrical connectors at both ends.



Optional Light Switch:

Since wires may have to be cut when removing the trucks, this is the opportunity to install an ON/OFF switch to control the car lights.  This will minimize power demand for daytime operation since you can't see the lights anyway, except maybe for the observation car tail lights.

In the example shown below a mini switch is mounted on the car floor using a bent aluminum bracket.

However, there is alternative to making your own bracket:

To accommodate Kadee 907 body mount couplers, the truck coupler tang has to be trimmed off (Described later in topic for Body Mounting Kadee 907 couplers).  But, this part can be used to mount a small mini switch.  The switch I used is a SPDT type, but only two terminals (center wiper & one end) are needed for a simple on - off function.  Illustrated below are the steps to prepare the tang for this purpose.


When wiring the switch - SPDT 3 terminal example used, one wire pair of same color / pattern is to be soldered to the center terminal, whilst the other pair of different color / pattern is to be soldered to an end terminal.  The other end terminal will not be used.  Choose one color / pattern wire pair long enough to go to the cut wires emanating from the floor at either ends of the car.  Use the different color / pattern wire pair long enough to go to the trucks.  (If using simple 2 terminal switch, it does not matter which terminal to solder the different wire pairs.)  A one pin connector can be used on each of the wires that goes to a truck so a truck can be later removed without having to cut wires.


Fuel Tank Removal:

With the lowered car, the fuel tank is going to have to be removed to prevent interference with the track since it's now too low, so one of its mounting holes (to be enlarged) will serve to install the switch.



Truck Installation:

Illustrated below is procedure for installing a truck using screwed in pivot and guide posts.
Note: If using a bolster with studs, washer and nut will be threaded on top of the standoffs.


One thing to watch out for is to make sure that the installed truck is touching against the roller dowels (or ball bearings if that type bolster is used).
I found some trucks did not due to manufacturing and assembly tolerances.  The small projection on the truck's sidefame is the cause.  When the truck rotates, it may leave  a telltale scrape mark on the bolster surface.  This condition can be remedied by filing down some of the projection as shown below.





Body Mounting Kadee 907 center set couplers:

The truck's coupler tang is too long and will interfere with the body mounted couplers.  So it must be cut short as shown below.


Once the car is lowered, the mounted coupler assembly is to conform to the Kadee 980 gauge.


To accomplish this, spacers are needed between the coupler assembly and the car's floor surface.  Also, leveling  shims may be needed for proper coupler alignment with the Kadee 980 gauge.

The following illustrations show the dimensions for making ABS plastic spacers that are needed on all cars, except for the end of the observation car (discussed later).




Shown below is how the Kadee 907 coupler assembly is to be stacked on the larger then smaller spacer such that the larger one overhangs smaller one.


The longer screw is a # 2-56 by 1 inch to be inserted in the coupler box hole, through the spacers that will thread into a hole to be drilled in the plastic part of the end bulkhead.   The smaller screw is a # 2-56 by 3/4 inch that is to inserted in the couple box shank (with lock washer), through the spacers and then thread into a hole to be drilled in the metal part of the floor.

After the coupler assembly and spacers are installed on the car, shims may be required to level the coupler so it aligns with the Kadee 980 gauge. Two Kadee supplied white shims were used on the example shown below, however, some other cars did not need any shims.

Shown below is the location to drill and tap holes in the car floor for mounting the Kadee 907 assembly




Observation Car End - Coupler Mounting:

There are 2 choices that will be presented here:

  • Choice 1 is to fabricate an end plug that will plug the gaping hole at the end of the observation car whilst accommodate mounting of the Kadee 907 coupler assembly.
  • Choice 2, the easier, is to obtain a 3-D printed "CamPac" end plug similar to the fabricated plug described for Choice 1.


Choice 1, Fabricating an end plug:

With the car lowered, the mounted coupler assembly is to conform the Kadee 980 gauge.


The observation car is a special case with respect to the end of this car.  Since this end has a huge cutout to accommodate the swing of a truck tang mounted coupler, it not only needs to be plugged for appearance sake, but at the same time serve as a mounting spacer for the Kadee 907 box.

Shown below is how this was done using a 3/8 inch thick rectangular shaped block of ABS plastic that was initially cut to fit in the opening, fastened down, and then scribed using a scratch awl to match the round end of the car.  It was then removed for finishing it, after which it was permanently installed with the Kadee 907 coupler assembly.


Illustrated below is the observation car with installed plug-spacer and Kadee 907 coupler assembly.


Choice 2, Obtain a 3-D printed CamPac end plug -
(illustrated below) by contacting Colin Camarillo via his website, and request this miscellaneous item. 

Note: The mounting holes to be established in the car chassis are to be the same as previously shown for the fabricated plug. Alternatively, the 3-D printed plug, when carefully placed, could be used as a template to establish the mounting hole locations. Holes are to be drilled and tapped for #2-56 thread - same as for the fabricated end plug.




Union Pacific 7 car Streamliner train operating on outdoor layout.


Appendix A - Example Car Lighting Control Methods


Depending on the Aristo-Craft (or Polk's GeneratioNeXt, aka PGN) factory production run date, car wiring may differ.  Early production runs had the power return wire from each truck pass through a floor hole rather than being accessible with ground lug to the chassis on the underside of the car.  Newest PGN production run cars appear to have added a pigtail connector at each end of  the car, presumably to connect in daisy-chain fashion from car to car to distribute power & return pickups from wheels of all cars, thereby virtually eliminating any illumination flickering tendency.  Another possibility is to provide power to all cars from a common source like a battery; if so, this would seem to need a control switch in each car.  At this time I don't know if the newest production run cars include a switch control for lights.  

The example diagrams that follow are of an interim production run representative of the car wiring as described in this article.

Factory Wiring



Shown below is an example factory wiring before any modifications are done.


Option A
This is the easiest option to implement, requiring no cut wires.  However, if removing factory truck bolster, you must cut channels in the bolster to slip wires out.


Option B
This option was chosen and described in this article.


Option C
This pertains to using a battery for car lighting with selection for Off
Note that battery voltage and capacity / size is to be determined.


Option D
This pertains to using a battery for car lighting, but still allows selection for track power or Off.



 Appendix B - Smoothside Car, Lowering & Body Mount Kadee 906 couplers

The Aristo-Craft Smoothside car construction is closely related to the Aristo fluted side "Budd" Streamliner car, so the same techniques done for the shorter Budd Streamliner apply to the longer Smoothside - except the coupler used is the Kadee 906 rather than the 907.  The Kadee 906 was chosen to accommodate operation of the longer length of the Smoothside car on 8 foot diameter track circle.  With a long length, long wheel base car, the projected overhang at its end becomes a problem, particularly on tight curve tracks.  In this regard, the greater flexibility afforded by the Kadee 906 long shank coupler and wider gear box opening is of notable advantage.

Kadee906couplercenteringSpringRelaxedAndCompressionAnnotated IMG 4782

The shank on this coupler has one centering spring that compresses when the coupler is pulled out in tension as would happen in train.  This feature is, also, used to advantage for locating the coupler box such that coupled car distance can be kept at a minimum whilst still allowing the cars to go around tighter curves down to 8 foot in diameter.

Now for the cars:

Aristo Smoothside Passenger cars are shown below lowered with George Schreyer's cast resin bolster.


Using the Fabricated bolster lowers the car about 0.05 inch more.
As shown below, the car on the left is equipped with George Schreyer's cast resin bolster, whereas, the car on the right is equipped with the Fabricated bolster - not much different but noticeable.

AristoSmoothsideLoweredWithGeorgeSchreyerBolsterLeftAndFabBolsterRight IMG 4039

Ultimately, I chose to use the Fabricated bolster, not only to height match with the lowered Aristo Streamliner car but, also, with the USA Trains factory height passenger car.
As can be seen below, the Aristo Streamliner and Smoothside cars are virtually the same height when both equipped with the Fabricated Bolster.

AristoUPstreamlinerWithKadee907andSPsmoothsideWithKadee906bothBodyMountsCoupled IMG 4506


As shown below, using the Fabricated bolster, also, provides  virtually the same car height match with the USA Trains fluted side metal passenger car.

USAT FlutedSideStreamlinerAndAristoSmoothsideLoweredWithFabBolsterRightComposite


Coupler Installation:

Once the Smoothside car is lowered, a spacer is required to body mount the Kadee 906 coupler assembly so it aligns properly with the Kadee track height gauge.
As shown below, the spacer can be made using a stack of Kadee shims, but since so many are required, particularly when doing several cars, it's best to make your own solid spacer.  A long 1 inch strip of ABS plastic can be obtained from TAP plastics at a relatively inexpensive price.  The TAP Plastics material thickness can vary from nominal, so it's best to measure one in the store closest to that desired.

AristoSmoothsideKadee906mountingFabSpacerOrKadeeIndividualSpacers IMG 3458



The drawing for making a spacer used for the Smoothside car is shown below.



Shown below are the hole locations for mounting the Kadee 906 coupler assembly on the Smoothside car.


The Smoothside observation car's round end hole locations are shown below.

AristoSmoothsideObsCarKadee906mountHolesComposite IMG 3373

The mounting of the Kadee 906 coupler assembly and spacer are shown below.


Shown below are the distances measurements between two cars coupled together on straight track.

AristoSmoothsidesCarDistanceOnStraightTrackMeasurementsComposite IMG 4759 


Truck Installation:

The the factory truck mount coupler tang along with some of the truck body must be removed from the truck so as to clear the Kadee 906 body mounted coupler and its spacer.  This should be done before the truck is mounted.



Though a fabricated bolster with roller dowels can be used on the Smoothside, the bolster type exemplified here is basic type with nylon ball bearings as shown below.

BasicReplacementBolsterWithBBholesOutlineDimensions IMG 4076

The nylon ball bearings can be obtained mail order from US Plastics.

USplasticsBallBearing IMG 4082


Installing the Fabricated bolster type with nylon ball bearings is shown below.


One thing to watch out for is that the installed truck is touching against the nylon ball bearings.
I found some trucks did not due to manufacturing and assembly tolerances.  The small projection on the truck's sidefame is the cause.  When the truck rotates, it may leave  a telltale scrape mark on the bolster surface.  This condition can be remedied by filing down some of the projection as shown below.

AristoSmoothsideTruckProjectionAnnotated IMG 4094



Shown below is a comparison of the cast resin and the fabricated bolsters on two different cars.





Shown below is an example Smoothside coach car end with Kadee 906 coupler aligned with the Kadee 980 track height gauge.

AristoSmoothsideKadee906alignsWithKadee980gauge IMG 3534

Shown below is an example Smoothside observation car round end with Kadee 906 coupler aligned with the Kadee 980 track height gauge.




Shown below are Smoothside coach and observation cars on an 8 foot diameter track circle.




Southern Pacific Daylight 9 car train operation on outdoor layout




Appendix C - Comparison of Aristo Streamliner, Smoothside & USAT Passenger Cars

Shown below are the Smoothside and Streamliner cars after modifications of lowering the cars and body mounting Kadee centerset type couplers (Kadee 906s on Smoothsides & Kadee 907s on Streamliners).



AristoUPstreamlinerWithKadee907andSPsmoothsideWithKadee906bothBodyMountsCoupled IMG 4506


Shown below are the USA Trains (USAT) Streamliner and Smoothside cars after modifications of body mounting Kadee centerset type couplers and with lowering the Smoothside car.  The USAT car did not need to be lowered.



Shown below are the weights of the Aristo Smoothside cars.


Shown below are the weights of the Aristo Streamliner "Budd" cars.



Shown below are weights of example USA Trains passenger cars.

USAT flutedsideMetalPassengerCarMeasuredWeightsComposite





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