HOW TO PICK YOUR MATERIALS

Steel

• Mild Steel

• Chromoly Steel

  • Easy to work with

  • Relatively inexpensive ($4/foot)

  • Light weight

  • Can be easily changed/modified

  • Readily accessible. Comes in a large variety of sizes and wall thicknesses

Aluminum

• Aluminum: Very stiff for its weight

• Harder to weld

• Needs more material to resist fatigue

• Can be difficult to repair

Titanium

• Light

• Strong (but not stiff)

• Absorbs shock

• Hard to weld

• Expensive

• Limited sizes

Brushless Electric Motors

• Very efficient

• More expensive

• Controller is more difficult to wire

Brushed Electric Motors

• Inexpensive

• Lower overall efficiency

• Controller is inexpensive and easy to wire

Batteries

• Choose carefully

• Batteries are one of the areas where you get what you pay for.

• Decisions to make:

  • What voltage does your car run at?

  • Higher voltage means lower current.

  • How much weight can you carry?

  • How much energy can you get at that weight?

  • Can your solar panels recharge the battery pack?

  • Is it a road race or a track race?

  • The 5 kilowatt kilowatt‐hour rule kw‐h = Amp‐hours x Voltage (at the 20 hour discharge rate)

    • Example: Four 12 volt, 84 amp‐hour batteries batteries in series 84ah x 48 v = 4032 watt‐hours or 4.032 kilowatt‐hours