Let's Talk Trucks!

Yes, prototype car builders do have standards. Most were developed by the Master Car Builders' Association late in the 19th and early 20th centuries.

 

Truck transoms (we call them bolsters) were to be at a specific height. King pins and side bearing designs for supporting the car were also standardized. This allowed use of a different truck when rerailing a car with damaged trucks, no matter where in North America teh wreck may have occurred. Trucks on prototype freight cars are not attached. The car simply sits on the truck with a kingpin to center it. The car can easily be lifted off and the brake rods disconnected to change the trucks if need be.

 

Passenger equipment and locos have locking kingpins on their trucks. Also more connections to the car than the brake rods. This means trucks are attached to the car and stay with it if lifted off the rails. Passenger cars used to be fitted with older freight trucks, often called 'shop trucks' when being rebuilt or overhauled as the basic kingpin/bolster set up is much the same.

 

Coupler heights are also standardized in prototype, as the couplers are mounted to the cars underframing. Car floor heights and underfrmaing are also close to each other in freight as well as passenger equipment. This allows a fairly common platform height as well as reducing the chances of one car over-riding the other in an accident.

 

Of couse in modeldom, just about every maker of RTR trains now has their own idea of what the "standard" for truck, carbody and coupler heights, even though the NMRA back in the 1930s set up standards for such to enable interchange and the ability to run equipment offered by different makers on all layouts. 

 

Yes, 3 rail O gauge also has standards, now largely ignored by the major makers.

With each producer having their own 'proprietary standard' for O scale, it has

become more challenging to change trucks, wheels and couplers to refit cars from 2 rail to 3 rail or vice versa. 

Hello Ed Bommer.........

Very interesting subject about the way the trucks are attached to the underside of the body, i learned something NEW today thank you Mr. Bommer

the woman who loves toy trains

Tiffany

Go to the NMRA website.   they have standards and recommended practices.   Wheel profile and gauge are in the standard sections and bolster/body height are recommened practices.

 

As Ed mentioned, most if not all 3-rail mfg ignore the NMRA practices and standards.   Most if not all 2-rail mfg follow them most of the time.   

 

Also there are standards and practices for coupler heights and installation.

 

All the toy-train mfgs have to do is read the material.  

Has anybody settled on using ONLY a certain brand of truck, or do most people (me included) "make do" with what's offered and try to make them work?

 

I usually leave the trucks that came with a car on, unless they are not the correct type.  I have a few that are roller bearing but need to be changed to solid bearing trucks and some caboose trucks that are incorrect.  If there's no correct model I try to use one that is close/similar in appearance.

 

Weaver makes some nice, inexpensive metal trucks with springs, that I try to use when I can.  I haven't made any bolsters yet, but a simple bolster to replace the dimpled flooring in some cars might be one way to go.  PSC makes bolsters, does anyone else?

My favorite hi-rail trick has become the latest Lionel Bettendorf.

Low truck top so easy to install on other cars. Sprung. Diecast. Runs very smooth and fast.

And I know using the lobster claw is sacrilege, but this version has the hidden tab for magnetic uncoupling and the neat little tab "cut lever" on the side for manual uncoupling.

Since my small scale hi-rail layout is all elevated at least five feet above the floor smooth running is VERY VERY important. I cannot afford to have any derailments that let a car fall off the track.

I have switched all the trucks on my Weaver cars to the newer Lionel diecast. I do not trust Weaver trucks at all, ever. The only disaster derailments I've had have been due to Weaver trucks.

The Atlas cars I have run well also, so I like those trucks too.

When I started building the old Athearn and All Nation box car kits to run on 3 rail track I noticed that most 3 rail RTR box cars don't model the bolster.  The 3 rail trucks (Lionel and MTH trucks) are higher to make up for the height the missing bolster would have provided.  In most two rail cars the bolster is modeled on the box car so the trucks are lower (like the old Athearn and All nation trucks).   What I've described is typical.  However there is a great deal of variation between manufacturers as mentioned above and these variations are increasing rather than becoming more standardized.  

Bob,

 

I make car bolsters in resin. Easy to drill & tap for mounting trucks.  Use them on wood, brass, styrene, etc cars........

 

 

I guess I also have a bit of an advantage in that the vast majority of my cars are scratchbuilt and I can standardize bolsters pretty easily to sit on what are my standard trucks now - Athearn with IM wheelsets.

Martin,

How easy is it to find the Athearn trucks, are they still being made?

 

I have cars from most of the present manufacturers and find that most can be modified so they ride fairly low and without having to install shims over 1/8" thick under the coupler pockets.  A few like the MTH cabooses and a few boxcars sometimes require the metal floor to be flipped so the dimple is inward.  Some of my cars have roller bearing trucks that need replacing with solid bearing trucks.

 

I would like to find a combination of truck/bolster/mounting system that would work and keep the coupler box shim to a minimum.

 

Do you have to use coupler pocket shims with the Athearn trucks and your bolsters?

 

How do you attach the trucks?  Some of my mods have forced me to keep the truck attaching screws loose so the truck will move, resulting in the trucks flopping around more than I would like.  A shoulder screw would be ideal, but finding one the exact height may be a problem (of course I could machine them down on my lathe, but I'd like to avoid all that work).

 

A common height truck (did Athearn make different styles of trucks?), a common bolster, and a common shoulder screw/attaching system for mounting them would be a great combo.

Bob,

 

I think that they are but they are harder to find now than in the past and more expensive pushing $10 a pair; not all that much actually, but then another $8-10 for IM wheelsets....

 

That dimple thing is something that just needs to be cut out of place or installation of a new underbody should be considered.  Hard to believe that folks find that to be acceptable under any car.

 

I don't think that I've ever used a shim under a coupler box - if I did that would be an indication that the car was riding too high.  I've found it odd that cars that still ride too high are tolerated and putting in a shim is an acceptable solution.

 

I mount trucks using 4/40 pan head or filister hear screws.

 

Yes, Athearn made Archbar, Andrews, Bettandorf, and Symington trucks.  Been working on re-stocking my drawer of Archbars.  All use the same truck bolster.

Thanks Martin!

 

I did a search on Athearn trucks and found a few online, plus I saw they made a separate bolster as well, although a plain bolster (no detail) should be easy to make.  Maybe a foot long piece in a bolster cross-section and just cut off each piece as needed?!?!?!

 

Yeah, having to add shims is a PITA and shouldn't be the norm.  I don't think all of my MTH cars have the metal floor w/dimple, but I need to check, I think 2 of the cabooses I have do not have them and 2 do.  Same for the regular rolling stock.

 

I only have 3 dozen pieces of rolling stock so anything I do won't take too much effort.

 

I think I'll get some Athearn trucks and compare them to what I have to see which ones I like the best.  the problem is the wheelsets can be another issue.  I know different brands use different points on the axles so combining brands of trucks and wheelsets can be tricky.

 

Settling on a bolster and truck type to eliminate the coupler shim is my goal, as well as having the cars ride at the same height.

The bolsters on Athearn trucks have tabs on the ends that lock the truck together.  They are loads of "fun" to assemble and inserting the springs is good for generating colorful and inventive language generally fractionally after the one's head intersects with the bottom of the work surface during a search for transiently airborne ones.

 

Wheelsets -- IM work perfectly with the Athearn trucks.

 

All of this would reduce to something simple if the concept of standardization could even be approximated.

 

Contact me directly if you want some sample bolsters; they may require a bit of sanding and/or shortening depending on the car and underbody that they are being added to, but being resin that's quite doable.  Just remember to drill & tap before mounting them!

Martin,

I took apart a couple of trucks the other day, know all too well what you mean about them being good for generating colorful language!  At least now I know where to look for any springs I might need...on the carpet

 

I'll keep you in mind for the bolsters, but I may try making my own.  I have some molding rubber left over from another project and could easily make a mold.

When working with the springs on any brand of truck, I have found it very helpful to put a piece of thread through the coils before trying to insert it or remove it.   It does no fly anywhere when it does not go in this way.   I always remember to do this after the first one flies away!

 

If the mfgs followed the NMRA standards and recommendations as they do in 2-rail, all the bolsters would be at the same height and the trucks would be much more interchangable.   Also the undersides of the bodies would be at a standard height, so body mount couplers would be easy too.

 

The standars are there, they are just ingnored.

prrjim,

THANKS for the tip!  Of the 3-4 I had shoot off into space, I only had 1 I couldn't find.  I did have a spare so I'm good to go.

 

The bolster issue...is this something that could be brought to their attention at York?  I don't go to York, but maybe someone who does (or if we had a list of queries to give the manufacturers like they do with DCS) could bring this to their attention.