• Mild Steel 
  • Chromoly Steel 
    • Easy to work with 
    • Relatively inexpensive inexpensive ($4/foot)
    •  Light weight 
    • Can be easily changed/modified changed/modified 
    • Readily accessible accessible z Comes in a large variety variety of sizes and wall thicknesses thicknesses
  • Aluminum Very stiff for its weight 
  • Harder to weld 
  • Needs more material to resist fatigue
  • Can be difficult difficultto repair
  • Light 
  • Strong (but not stiff) 
  • Absorbs shock 
  • Hard to weld 
  • Expensive
  • Limited sizes
Brushless Electric Motors 
  • Very efficient efficient 
  • More expensive 
  • Controller is more difficult to wire
Brushed Electric Motors 
  • Inexpensive Inexpensive 
  • Lower overall overall efficiency 
  •  Controller is inexpensive inexpensive and easy to wire 
  • Choose carefully  
  • Batteries are one of the areas where you get what you pay for. 
  • Decisions to make: 
    • What voltage voltage does your car run at? 
    • Higher voltage voltage means lower current current. 
    • How much weight can you carry? 
    • How much energy can you get at that weight? weight? 
    • Can your solar panels recharge recharge the battery battery pack? 
    • Is it a road race or a track race?
  •  The 5 kilowatt kilowatt‐hour rule kw‐h = Amp‐hours x Voltage Voltage (at the 20 hour discharge discharge rate) 
    • Example: Example: Four, 12 volt, 84 amp‐hour batteries batteries in series 84ah x 48 v = 4032 watt‐hours or 4.032 kilowatt kilowatt‐hours