What are "roller bearing trucks"?

[jazzharmonicat]

I ordered some Bachmann "roller bearing trucks w/o wheels" off ebay but not sure what to do with them.
I don't see any roller bearings in them.  I know some people order them to upgrade the couplers.
But I got some very nice looking cars that the trucks won't swivel (sposed to but kind of stuck -- and that makes the cars not stay on track going around curves) and I was hoping to use these to not only allow the trucks to swivel properly but also to have minimum rolling friction, like the really long N gauge train (pulled by only one locomotive) that I saw at the World's Greatest Hobby On Tour show in Fort Worth earlier this month.
So I gather that these trucks I bought are maybe only for Bachmann cars (?), but what do I do with them?  Am I supposed to get some wheels that have roller bearings in them?  Or do these tiny plastic trucks have roller bearings hidden in the wheel axle holes?
  I'm confused.

[Desertdweller]

That's a good question.  In a model railroad sense, "roller bearing trucks" means trucks that are models of trucks that use roller bearings on the axles.  As opposed to models of trucks that use friction (journal) bearings on the axles.

The model trucks do not actually contain roller bearings, as model Diesel locomotives do not actually contain Diesel engines.

You probably have noticed that model railroad trucks are generally made from an engineering plastic that is rather flexible.  The axles have pointed ends that ride in little cups in the truck side frames.  Both "roller bearing" and "journal bearing" model trucks have this method of holding the axles.  They use the flexibility of the plastic to allow the rigid axles to be popped in and out.

As far as how the trucks are attached to the cars, different manufacturers have different ways of doing this.  It generally involves a pin or a screw inserted into a hole in the car frame.  It is possibly to mix brands of trucks under a car.

Micro-Trains, in their N-scale trucks, include a variety of pin sizes and spacer washers to allow mixing of trucks.  Or, you can try plugging the pivot pin holes in the bottom of the cars and drilling them out to whatever size you need.

If the trucks are giving you trouble, try checking to make sure the axles are square in the truck frame.  Also, check for proper wheel gauge (distance between the backs of the wheels).  You can check this with a Micro-Trains coupler gauge.

Make sure the truck can swing freely from side to side.  You might have a bind somehow at the truck pin, or the truck-mounted couplers may be snagging  on the car underbody.

Les

[skipgear]

A picture is worth a thousand words......

http://www.spookshow.net/trucks/trucks.php

You can see the differences better there.

[jbrock27]

Jazzy-

If I understand what you are saying, you have the trucks that hold the wheels, but no wheels?  Is that correct?
If so, you will need to buy "wheel sets" to put in the trucks-2 for each wheel.  You will have to find wheel sets that fit the trucks you now have.   These are two wheels joined by the axle. 
What manufacturer are they?  Matching brands made be the way to go, but not absolutely necessary.  What is necessary, is matching the length of the wheel sets to the space in the trucks so they fit.   Measure the inside space of the truck and go about your search from there.  Searching on line should help. 
I hope that helps.  Good luck.

[James in FL]

Everything you probably want to know (and more) about trucks here;

http://mrr.trains.com/~/media/import/files/pdf/4/c/c/mr_pi_5-06_freightcartrucks.ashx

Spookshow is also a good reference:

http://www.spookshow.net/trucks/trucks.php

Good luck

[Ken G Price]

I get that he bought these trucks believing that they have real N scale roller bearings built in to them.
Not realizing that it meant a type of 1:1 trucks as used on the real thing and not a N scale model train

[jazzharmonicat]

Cool info
Thanks guys

[Ken G Price]

Your welcome.