Before building a car, call the Technical Director, Bob Lechner, 619 754-5089 and let him know.

It can save you much time and money, and grief. If you build a car and it doesn't pass the inspection you don't race, and someone will have very disappointed children.

The guiding philosophy behind Orange Crate Derby is that it is fun for kids. Our motto is “Family, Fun, Fair.” The cars are designed to be as simple but safe as possible, and can be built by adults and kids with commonly available tools and parts. It is not an exercise for adults to compete against each other using Aerospace Engineering skills or manufacturing techniques to win at all costs.

These are the specifications by which all new cars will be inspected for. Cars built before this may be ”grandfathered” in by the Technical Committee. An older car may be required to update parts to make it safe and current.

  • Build the cars to these specifications and let the kids help. They love to name them, paint them and drive them.
  • New builders must attend at least one “Build-A-Car “ clinic. Bring your unfinished car and ask questions! The dates are shown on the website.
  • Use the photos and captions to build your car. If you have any questions, call Bob Lechner, 619 754-5089.
  • The frame of the car can be no longer than six feet. A 2x4 bumper may be added to the front.
  • No part, including the wheels, can extend beyond the frame.
  • The most important aspect of design is the Orange Crate. Build it to the specifications shown. No exceptions.
  • Use the fully threaded axle rods available at Home Depot or Lowes.
  • Do NOT add fins, spoilers, exhaust pipes, windscreen, steer horns, rear view mirrors, fuzzy dice, etc.
  • Use the examples shown to guide the construction of the car.
  • Steering wheels are to be made of wood.
  • No metal (except those required, like hinges, cables, pulleys, etc) to be in front of the driver.
  • ALL cars will have safety sides to protect driver.
  • The axles will be under the frame. Use the examples shown to guide the construction of your car.
  • No added weights.
  • The brake housing must be open and visible
  • Read race day instructions


Important! – Contact Bob Lechner before you begin working on a car 619 754-5089! We can loan you a car to copy while you build yours. (It makes it so much easier!) Plan to attend the build a car clinics to get approval on brakes, steering and design elements before practice day!

These instructions will describe 7 areas that make up a complete car. Click "Read More" button for step-by-step directions in each section.

  1. Frame (or chassis)
  2. Steering 
  3. Brakes
  4. Axles
  5. Seat and Side Panels
  6. Crate
  7. Bumper

Download the list of hardware and lumber to purchase. You may download a pdf file with directions and sketches if you want to print something out.

Wood Needed

This is a picture of the plywood and boards needed to make the car. figure sk-1 This drawing (sk-1) shows the basic lumber required to build a car. It consists of two 8 foot long 2 x 2s, two 8 foot 2 x 4s, one 8 foot 2 x 8, and ...
Read More

Hardware Needed

This is the hardware to assemble the car ...
Read More


Frame – Cutting the Plywood

SK 2
Figures sk-2 and sk-3 show the recommended cutting of the sheet of plywood.  Cut the cross piece first. figure sk-2 figure sk-3 ...
Read More

Frame – Gluing and Screwing Together

The two pieces marked as “frame” are glued and wood screwed together as shown in sk-4 and sk-5. figure sk-4 figure sk-5 This results in a frame 72″ long, 19″ wide, and 1 1/2″ thick. TITEBOND III Glue should be used. Make sure no wood screws are placed where the ...
Read More

Frame – Cutting the Brake Slot

SK 6
After fastening the two pieces of plywood together, drill four holes for the brake arm slot and cut openings as shown in sk-6 for the brake arm. figure sk-6 Use a saber saw to cut out the slot for the brake arm ...
Read More

Frame – Steering Cable Holes

Drill two 1″ holes for the steering cable and drill a 3/4″ counter sink for the brake cable eyebolt Locate and fasten a mending plate to the underside of the frame by the two holes for steering cables. Attach pulleys for the steering cables as shown ...
Read More


Steering Frame

Construct the steering frame from 2″ x 4″s, a 1″ hole is drilled through the back support and halfway through the front support for the steering rod. The holes should be approximately 1 1/4″ down from the top of the supports. Build the steering housing first, then place it on ...
Read More


Brakes Housing

Cut two brake housing supports and one top per dimensions on sk-10. figure sk-10 The brakes consist of three components, the housing, the arm and linkage assembly, and the pedal.  The housing is made up of two supports and a top piece, as shown in figure sk-10. Note that front ...
Read More

Brake Linkage

Cut three pieces of 2″ x 4″ 8′, 9″ and 14 1/2″ long. The 8″ and 9″ pieces will form the brake linkage and the 14 1/2″ piece is the brake arm. The arm and linkage assembly goes together as shown in figure sk-13 and is then fastened to the ...
Read More

Brake Pedal

The brake pedal is made from a 8″ x 10″ piece of plywood with a piece of 2″ x 4″ fastened across its top.  This pedal is fastened to the frame with two hinges. It has an eyebolt through its top part, to which the brake cable is fastened.  The ...
Read More

Brake System

SK 26
Once all the brake parts are assembled the brake cable and spring may be attached as shown in figure sk-26. figure sk-26 ...
Read More


Axles Materials

Shown above is the hardware needed for the front axle and steering system. The rear axle is similar to the front ...
Read More

Axles Step 1

SK 19
figure sk-19 Cut two 2″ x 4″ pieces 29 3/4″ long. Each piece has a 1/2″ x 1/2″ groove cut along its length, offset from the center per sk 19. This groove is for the 1/2″ diameter threaded axle rod.  The groove should be a little on the tight side ...
Read More

Axle Step 2

SK 21
figure sk-21 The rear axle assembly is fastened to the underside of the frame with 1/2″ bolts. Drill a 1/2″ hole in the middle of the front axle, located as close to the threaded axle rod as possible.  Center the axle so that this hole is 6″ from the front ...
Read More


Steering Wheel

The steering wheel can be a piece of wood (plywood recommended) cut into a circle about 8″ in diameter. A block of 2″ x 4″ with a 1″ hole is then fastened to the wheel which is then fastened to the steering rod. Use a 3″ wood screw through the ...
Read More

Steering Cable

Cut the small end off the 1″ x 3/4″ pvc reducer brushing, pass the 1″ steering rod through the rear support and slide the pvc reducer brushing onto the steering rod with the flange toward the support. Continue passing the steering rod until it enters the hole in the forward ...
Read More


Crate Construction

The crate is the signature piece of the car.  It MUST look like an old time orange crate. The frame of the crate is made of 2″ x 2″ wood (1 1/2″ x 1 1/2″).  The front and back pieces are rectangular in shape.  The front piece has four sides ...
Read More


Seat and Side Panels

figure sk-32 figure sk-33 Cut the sides, sk-33, and seat parts, sk-34 according to the dimensions in the sketches. figure sk-34 The seat is made from plywood as shown in figure sk-34.  The two runners under the seat are to provide clearance for the brake cable.  The seat will be held ...
Read More

Bumper Construction

All new cars must have a front bumper, made from a 28″ long 2″ x 4″. It is highly recommended that existing cars be fitted with a bumper ...
Read More



SK 27
figure sk-27 The wheels are 10″ diameter ball bearing, rubber rimmed disks, mounted on the ends of the axles as shown in figure sk-27.  Care should be taken not to over-tighten the wheel retaining lock nuts.  A recommended procedure is to just snug up the nut, and back it off ...
Read More