Reference Pages
Type of Drawings
Dimensioning References
Sectioning References
Thread References
Electronics References
Title Block Downloads
Engineering Videos

Reference Arduino and Electrical Components
Note: All files are zipped.  Be sure to remove CAD files and place in folder with model(s) that are associated with the downloaded parts
Download File: Arduino Parts   
OnShape Links
     Arduino Boards
     Electrical Sensors
     Misc. Electrical Parts
     Robotic Arm
     Servo Motors
     Servo Brackets    

Machining and Process References
Reference: Types of Hole Creation: Drill, Bore and Ream
Reference: Drill Bits and Materials 
Reference Video: Boring Holes

Drafting Tools
Architecturial Trianguliar Scale (Need 11 x 17 paper to print on)
Engineering Triaguliar Scale (Need 11 x 17 paper to print on)
Full Scale 6" Ruler
Full Scale by 1/16"
Full Scale 15cm by mm Ruler
Full Scale inches (12") and cm/mm
45 Degree Triangle
30-60 Degree Triangle
Protractor

Website: Printablerulers.net: Free Download of various measuring tools