Building the racer is most of the challenge and half the fun! The important thing is to not take it too seriously... some over-engineered racers have been flops, and some simple designs have been real winners.

The best way to come up with a racer design is to look at what other people have done and go from there... So instead of step by step instructions here are some guidelines and then links to other resources.

The basic racer recipe calls for:

1. A handheld power tool (typically a grinder, belt sander, or circular saw)
2. Wheels (inline skate wheels are cheap and plentiful)
3. A chassis (???)

The best place to find a Power Tool is at a junky thrift store, garage sales, or craigslist. Good working tools can usually be found for $10-$20. Skates can be bought by the cartload an many thirft stores or kiddie-stuff garage sales. They are basically shoes, and kids outgrow shoes, right? Same with skates... For the chassis you can use anything that makes sense, wood, metal, zip ties... Most hardware stores sell perforated angle iron that is easy to cut with a hacksaw and has nicely spaced holes in it, like the metal from an "erector set" (mecanno for you Brits) only bigger.

There are not many constraints on your design, but there are a few things to keep in mind:

1. Track dimensions & material
2. Power
3. Safety

Track dimensions vary from race to race, but a typical (American) track is made of 2x4 lumber and plywood. The 2x4s are stood on edge as guide rails with 12 inches of clearance in between, attached to a plywood base. A typical track is 50 feet long with an additional 10-20 feet of runout. *ALL SIDES* of the track rails can be used by the racer, i.e. you can build a "monorail" if you are so inclined.

Left: Track & power at the 2007 Seattle Races


Below: Track diagram

Power (and extension cords) are typically supplied by the race organizers. Your racer just needs to have a standard cord-end on it, and the trigger should be taped down or otherwise modified to be 'always on'.

Safety considerations are specific to the event, but there are some things to be aware of, especially for novice builders...

• grinders and saws spin *VERY* fast, so be careful what you attach to the "wheel". In general you should only use manufactured wheels that are mounted securely to the arbor, building a wheel from scratch is not recommended as it may come flying apart when spun up to 10,000 RPM.
• TODO: More safety...

If you have *ANY* concerns about safety its best to consult with an experienced racer, a good place to do that is in our Web Forum

Below you will find links to resources that will help you build a racer. You should also check the media page for racer ideas, or ask in the forum.

Remember: this is about fun! Some of the best racers are cobbled together on the sidewalk with a roll of duct tape, and some of the overengineered racers dont even make it down the track...

Bre Pettis from Makezine put together a great video that captures the PTR experience, you can find it here in Bre's blog

Jer from HazardFactory put together a tutorial on how to make a racer from a skillsaw, find it here at instructables.com