Passive rolling car construction tips:

A typical passive car has 2 trucks mounted below a deck made of 2 (actually 1.5 inch thick)  by 12 (acutally 11.5 inch wide) treated pine board dimensional lumber cut to be 3 feet long. The trucks are made from “2 by” wood with dimensions shown in the picture below.   The trucks are attached to the deck with a lag bolt (bolt from above the deck through a washer, through the deck, through another washer and into the top surface of the truck below point a.  3 inch flanged “train wheels” are made by cutting a disc of 1/8 to 3/16 inch thick polypropylene, and lag bolting through a roller skate wheel, flange disc, spacing washer(s)  into the wood truck as shown below.   If different size roller skate wheels are used, the flange disc needs to be adjusted to create a ½ inch flange. 

This simple construction provides fairly frictionless wheels.  A parts / suppliers name /internet  location / approximate cost list is provided at the end of this document.  

dimentions:  A= 7.5 in.    b=  6 5/8 in   c=  10in   d= 5.5 in   e= 11.5 inches

part 1 is a roller skate wheel

2 a 1/8 to 3/32 inch thick round disc of polypropylene, cut to create the ½ inch wheel flange

3 a 2.5 inch long lag bolt to connect the wheel, flange through a spacer washer (not seen) to the wood truck.

4 at red arrow is a connector coupling hook

This truck is connect via a ½ inch diameter 3 inch long lag bolt from above (see picture below) to a point in the middle of the truck near point  to allow the truck to pivot on the car deck near point “a” in the picture above. 


Any type of car can be made of pine or plywood to attach to the top of the deck to make a child carrying passenger car and caboose, or any passive car.  Car decks are usually made of a 3 foot long section of 2 by 12 pressure treated lumber.  Trucks are made of pressure treated lumber .

 dimensions a=  36 in   b=  11.5 in  c=  8  d=  11.5 in  e=  11.5 in

Same construction used for caboose.  Note that  a caboose body, made from pine shelving boards, was mounted onto a pressure treated deck frame and trucks  (yellow wood), seen in the front view picture of the caboose.

Car couplings: simple screw in eye hooks.

Wheel spacers: 

Washer(s) can be inserted between polypropylene flange and truck to increase wheel spacing slightly, if needed.  At least 1 washer should be used for friction reductions.