We made downhill wooden racers! These racers can go down slopes on paved roads or dense grass. They have small wheels so they speed up quickly but don't have a high top speed.

You can change up the design quite easily too!

Step 1: Research!

Search for soapbox derby, wooden go-kart, downhill racer - on instructables, google, and youtube. Look at the pictures and videos, and decide what you want to make!

Step 2: Materials and Tools

Materials:

Pine 2x4s or similar wood. 3 meters per car is enough, but get extra if you can.
0.5 square meters of 2cm or thicker plywood. thick enough to make a seat.
4 castor wheels, non-swiveling or swiveling (I prefer non). at least a 10cm diameter, the bigger the better (and more expensive)
x20 3 to 3.5 inch wood screws, with washers
x6 5 inch bolts, nuts, washers. thick, at least 1.5cm thick. big 2cm thick bolts would be great.
Any kind of paint and brushes (I used spray paint with air masks)

Tools:

Minimum:

Hand saw, hand drill with drill bits smaller than your wood screws, ruler, pencil, screwdriver, 2 wrenches that fit your bolts, 2 C Clamps

Better tools:

Power tools! Electric drill, skill saw, jig saw, electric sander and sandpaper, more clamps to hold the wood down, measuring tape, speed square. This is a fun project to use power tools on, so I suggest adding them in where possible ;)

Step 3: Play With the Tools and Materials

We made little dolly carts, and raced them down a cardboard ramp. Time trials!

This let everyone get familiar with the skills and rules needed for the project.

Step 4: Measure and Cut

Everyone can decide their own car length and wheel base length. Factor in the riders weight and strength of the wood to make sure it's not too crazy long, because then the wood will bow/bend downward too far with their weight.

Use: Wood, handsaws, clamps, measuring tape, pencils. optional: sandpaper

Step 5: Add Bolts

Put two or three bolts in the back, and one bolt in the front. The one in the front should swivel for steering.

Use: Electric Drill, Drill Bits, Nut/Bolts/Washers

After, you will have a Wooden i shape (capital "i"). Test out it's length, like the kid in the picture.

Step 6: Add Steering Rope (optional)

We added a rope to hold onto, even though you can also steer with your feet. We attached it by drilling holes, but be creative and attach however you like. Make sure to leave room for the wheels and brakes.