• ANSI 25: 1/4” pitch, 115 lb working load (McMaster-Carr)
• Chain stretches/wears over time
• If lengthening is significant chain will skip teeth
• If this happens, chain will need to be tensioned
• Higher tension causes chain lengthening to occur faster
• If tensioning is not used, it is important to space wheels such that a
whole number of chain links are need to span the distance
The amount of tension in the chains is largely effected by
sprocket size
• Assuming torque is fixed, a larger sprocket is equivalent to a
longer moment arm, and therefore less force (tension)
• Max torque is dependent on the amount of friction, which is a fixed
value
• To minimize tension, choose the largest sprocket that provides
enough ground clearance between the playing surface and chain
Bennett, Ben. "Drivetrain Design." Drivetrain Design (n.d.): n. pag.
www.simbotics.org. 22 Oct. 2011. Web. <www.simbotics.org/files/pdf/drivetraindesign.pdf>.
Simbotics did an excellent analysis of many common drive trains used in first and the though process behind a reliable design, I encourage everyone to give it a look