Lowered Floors for 40 Foot Cars

Installing Aristo-Craft's lowered floor assembly in the 40 foot freight cars Article.
Ted Doskaris
April 22, 2007
Revision GE-D

Sometime ago I decided to install the Aristo-Craft, ART-29706, lowered floor assembly with its shallow bolsters starting with my Reefer cars, particularly the PFE cars.
This makes the cars closer to the trucks and less overall height from the rail head, thus more realistic.
Of the 3 Aristo car types (Box car, Stock car, & Reefer car) they are virtually the same with respect to the floors as well as to their removal & installation - except the Reefer includes an extra wire foot stirrup below its double side doors.  I have retrofitted approximately 60 cars with the lowered floors.
(BTW, the Aristo 40 foot gondola and flat cars do not readily lend themselves for retrofitting the lowered floors because the floors are more recessed in these cars. Thus, the truck mounted coupler / tang can interfere with the end bulkhead bottom area - necessitating modifications – perhaps best done with body mount couplers.)

One BIG revelation I came upon whilst doing this task was discovering that all my cars had their original floors installed backwards! That is - the AIR tank end should be placed closest to the NON brake wheel bulkhead.
I had looked in my books to verify the proper placement of the air brake hardware with respect to the car's brake wheel bulkhead.
Of particular importance is the book,
"Pacific Fruit Express PFE", published by Signature Press, ISBN 1-930013-03-5,
pages 168 - 170 inclusive of photographs and an engineering fold out drawing of the PFE car between pages 432 and 433.

The book pictures and drawing clearly show that the floor's large AIR tank should be closest to the car's NON brake wheel bulkhead whilst the smaller brake piston cylinder should be closest to the brake wheel bulkhead. This orientation is unlike virtually all Aristo-Craft Reefers, Box cars, and Stock cars that I have examined to date.
It is very possible that the Aristo factory has been assembling all these type cars incorrectly (not just the reefers) for more than a decade!
In this regard, it is my understanding that Aristo-Craft is in the process of correcting this factory practice for future production runs. I am optimistic that the factory will in time correctly produce the cars with the proper floor orientation based on communication between Aristo and myself with respect to this matter.

Shown below is the Aristo-Craft PFE reefer car with its factory assembled wrongly oriented floor with respect to brake wheel bulkhead:

PFE reefer with its brake apparatus parts shown. (Note the location of the air tank with respect to the brake wheel is indicative of this floor being installed in the wrong direction.)

Now for some preliminary floor removal & installation tips:

Remove the truck assemblies then the 2 small screws - one each - below the side door at the floor, and then the 6 long screws that retain the floor to the car body shell.
Be aware the 4 corner foot stirrups retaining lugs protrude into the side of the car body and will restrict the floor from being removed.
Having done many cars of various types, I found that only one foot stirrup need be cleared by pushing against the lugs until they are flush with the insides of the car body.
Pry out the floor around its sides using small flat blade screwdrivers or knife.
Then start lifting out the floor at the corner nearest the one with the cleared foot stirrup lugs.
The floor can now be extracted past the rest of the 3 remaining and protruding stirrup lugs. (Installation works similarly in that you slide the floor under the 3 remaining foot stirrup protruding lugs, and force down the corner near the cleared foot stirrup lugs. I use a plastic mallet to seat the floor.)

Below is an example Aristo SP 40 foot box car showing the 6 long floor screws that secure the floor to the car's body shell:

And the same car showing one of its long floor screws installed within the car's interior:

And the same car showing the small screw installation at its side at the floor:

Below is the same car showing one of differing type Aristo factory foot stirrup installations methods with this one employing the melted plastic method to the protruding lugs! Some production runs just have pressed in foot stirrups with the lugs protruding. On those you merely force the lugs to be flush with the body shell to facilitate floor R & R:

And below is the same car showing its floor being slid out or into the body shell in such a way as to clear the foot stirrup protruding lugs:

And the same car new lowered floor being installed using a plastic mallet to seat it to the body shell:

Aristo's newer production run lowered floor assembly kits include the brake hardware so you don't need to salvage it from the original floor. However, it is best to reuse the air tank if it has script on it since the kit just has a plain black painted tank:

Example car air tank is shown below being removed from the original floor by prying it up with a large flat blade screwdriver. Since the tank has unique script on it is best to use it rather than the plain all black tank that comes with the lowered floor kit:

And the new lowered floor slots being trimmed of excess plastic flashing to accept the air tank:

The car air tank is easy to install into the new lowered floor slots using a plastic mallet. No need to glue as it is a friction fit:

The new lowered floor can be trimmed with a file so it will better fit within the body shell. Tolerances vary and sometimes this helps for easier installation due to tight fittment.

Now to proceed with the new Reefer floor installation:

When installing the new lowered floor, I oriented it properly. (There is no "key" in the car or floor that requires its installation in a given direction, so all you have to do is turn it around 180 degrees.)

Aristo-Craft 40 foot freight car type Old and New lowered floor bolster comparison (the one below is the new floor and has the shallow type bolster):

PFE reefer car with floor parts removed (Also shown is the side view of the newer floor next to and below the original floor):

Original production runs of Aristo’s lowered floor assembly, ART-29706, did not include new brake linkage and air tank parts. When salvaging such parts from the original floor, I found removing the plastic brake linkage hardware to vary from prying it up with a flat blade screwdriver - from an apparent press fit - to having to break off the little unseen fastener pins whilst prying it. This is because the factory appears to use glue on a random basis! When installing the linkage on the new floor, I used CA glued as needed.

PFE reefer with new lowered floor and former hardware removed from the original floor:

PFE reefer floor showing holes drilled by factory in its side to accommodate the wire foot stirrup:

PFE reefer with new floor (once installed) must be drilled with a small drill bit to allow for installation of the wire foot stirrup. I used a pin vise for this operation.

The PFE reefer requires 6 long screws to mount its floor to the car's body.
(It is helpful to open the side doors and ice hatches to see how the long screws are aligned with the small plastic bosses within the car body. Use care when setting the car upside down on its rooftop with respect to the ice hatches and latching hardware that may come loose.):

The PFE reefer's new lowered floor requires use of a flat head bolster screw rather than the protruding round head screws of the original floor to avoid interference with the top of the truck side frame. Such interference effectively reduces the amount of truck spring compliance / compression. The lowered floor assembly does not include flat head screws, and It would be desirable for Aristo to include the flat head screws on future production runs.
I used a 4-40, 5/16 inch long Philips black oxide type screws installed in the bolster - see example below where the Xacto knife is pointed:

The new lowered floor has one different (repositioned) mounting post location for the transplanted, former brake linkage.
(To avoid possible wheel flange rubbing & squeaking when operating the car on curve tracks, the shown unattached link projection should be cut slightly shorter and / or glued down on the floor post.)

Ancillary Issues:

Truck brake shoes need attention if installing metal wheels:

Before transplanting and installing the truck assemblies to the new floor, check the trucks' brake shoes projections:

To avoid possible problems the Bettendorf truck type brake shoes of the older production run cars must be trimmed when using Aristo metal wheels. The ART-29111 metal wheels are slightly smaller in diameter than the standard plastic wheels, and the brake shoes will tend to touch the rail head and get hung-up at the rail joints and turnout frogs. I first discovered this as the cars would make a noise when the shoes hit those track areas – typically on the curves - and sometimes the shoe would come out and the springs fly!
I resolved this by trimming off a little of the 2 lower projections on each brake shoe. The newer Aristo shoes are made with less projection as the factory has addressed this problem some time ago.

Below is a picture of Aristo-Craft Bettendorf truck brake shoes of the older cars that must be trimmed to prevent rubbing on rails when metal wheels are retrofitted since the metal wheels are slightly smaller in diameter than the original plastic wheels. The right side truck in the picture has had its shoes trimmed:

The upside down truck shown at the bottom of the below picture is of the older version with projecting shoes that are prone to snag on turnout frogs or track joints if not trimmed. (For comparison, the newer production run truck assembly with factory corrected brake shoe is shown at the top of the picture.)

Trimming can be done with a small cutter or using a file by removing a very small amount - parallel to the track rail head:

Below are Aristo-Craft PFE reefer cars compared. The lowered floor version car shown to the right with the most noticeable difference being the spacing between the truck and floor.

A more distant view:

Aristo-Craft PFE reefer cars showing perspective view with the car in the foreground being the lowered one:

Trucks & spacer washer issues:

The newer production run Aristo-Craft 40 foot cars include the new lowered floor assembly - albeit installed with the wrong orientation as my CN reefer was.
I noticed these cars have a tendency to wobble too much from side to side.
See the picture below of Aristo-Craft CN reefer with truck removed showing metal washer on the car's floor bolster. (The cars with the older floors do not have this washer installed.)
(This factory practice is more appropriate to the Aristo EVANS type cars as the ones I have exhibit virtually no articulation.)

When changing plastic wheels to metal wheels on this car, I moved the washer from the car bolster pivot to the truck bolster so that car wobble is reduced.
(Admittedly, the washer will somewhat add to the truck’s spring compression distance, but the trade-off is much worse with excessive car wobble – resembling that of a bouncing figure found on the back package shelf of certain car cultures of the 1950s.):

Bettendorf truck side frame flashing issues:

Aristo's Bettendorf truck side frame flashing - if not trimmed off - can interfere with the truck bolster uppermost travel as it won't seat fully into the pocket. This also increases the difficulty when installing springs, and once the truck is installed on the car it can cause the coupler tang to vertically move the coupler up when the car's truck springs are loaded -e.g. compressed - and back down when unloaded.
Moreover, the newer lowered floors allow for less truck spring compression as compared to the original floors. This is due to less distance between the top of the truck side frame and floor bolster. Even the little added travel afforded by the trimmed flashing is helpful and as such it is important that the Aristo factory be aware of this issue, particularly considering the newer production run cars now include the lowered floors.

(It may be noticed that I elected to install Aristo’s miniature ball bearing inserts, ART-29411, into the side frames as shown above, too. This is another reason to clean off the plastic flashing located in other areas.)

The Aristo Bettendorf truck coupler to axle spacing is minimal after it is mounted to the truck's bolster tang. This is a design limitation, and the small clearance invites the coupler tang to move up when the car is loaded as the butt of the coupler touches the axle.

An automotive feeler gauge is used to measure the clearance:

The measured clearance totals .037 inch in the example Aristo Bettendorf truck as shown below:

The below picture shows two cars at their coupler ends (both cars have the retrofitted lowered floors):

The below picture shows the two cars at their coupler ends with the car at the left being loaded (pushed down - springs compressed) and the coupler is still level -albeit lower than the other car's coupler on the right. Unlike what the below picture shows, if the flashing were not trimmed off, the spring compression travel is somewhat lessened and the coupler tang will tend to tilt upward rather than remain level - albeit a bit lower:

Some Bettendorf truck history is in order as Aristo’s 40 foot type cars model this type truck:

Below is William P. Bettendorf's Truck patent number, etc.
Patent No. 740,617
William P. Bettendorf
Car Truck
Application filed June 1, 1903
Patented October 6, 1903

To see the patent, below is a USPTO special shortened URL allowing access to the Bettendorf truck patent:
Once there, click on the "Images" box to view the first page of the patent in a browser window, then use the yellow colored arrow keys located in left column to navigate to the remaining pages. (Note: the “AlternaTIFF” browser plug-in is required by the patent office web site for viewing the patent images.)

William P. Bettendorf patents a cast-steel truck frame with integral cast journal boxes.
Railroad Historical Almanac 1900 - 1919


See below link for prototype picture example of a Bettendorf truck - albeit a newer version:


When looking at the picture note the far side view of the left wheel shows flutes on the inboard side like that of Aristo's molded plastic wheels, whereas the right wheel is devoid of the flutes as are Aristo metal wheels.


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