Densities

If you multiply the density of an object by it's volume you will calculate it's weight. Below is a list of common robot building materials and their densities

Plywood 0.5 - 0.9
Titanium 4.85
Stainless Steel 8.1
Aluminum 2.7
Kevlar 1.44
MDF 0.9
Mild Steel 7.8
Polycarb 1.2
UHMW(Chopping board) 0.9


Weights

To help fight the eternal fight of "My robot is to heavy" Here is a list of common robot parts and their weights


24Volts worth of CP2400 NICADS 1.3KG
TR Magna Flat Fan Motor 0.7KG
100Watt Scooter and wheel unit 1.9KG