Solve any belt drive
Solve for driven speed, driven or driver pulley size, or motor speed; start from a centre distance to get the belt length or from a belt to get the centre distance. Open or crossed belts, with slip for friction belts. Results include speed ratio, belt speed, exact pitch length, wrap angle on each pulley, free span and rim gap.
Exact, not approximate
Belt length uses the exact open- and crossed-belt formulas, and centre distance from a belt length is solved numerically to full precision. The textbook approximation is still in the report so you can compare.
Timing belts by the tooth
Sixteen profiles including GT2 and GT3, HTD 3M/5M/8M/14M, T2.5, T5, T10, AT5, AT10, MXL, XL, L and H, or a custom pitch. The app gives the two whole-tooth belts either side of your target centre distance, the centre distance each really gives, and a warning when fewer than six teeth mesh. Made for 3D printers, CNC machines and conveyors.
Multi-stage drives and tension
Chain up to six stages and see speed, torque and power on every shaft. From power and the drive, the capstan equation gives tight and slack side tension, installation tension, hub load, span frequency for a sonic tension meter and mid-span deflection. Units switch between millimetres and inches, with fraction input like 3-1/2.
Questions
- How do I calculate pulley RPM?
- Driven RPM = driver RPM × driver diameter ÷ driven diameter, slightly less for friction belts because of slip. Enter any three values and the app solves the fourth.
- How do I calculate belt length for two pulleys?
- For an open belt the exact length depends on both diameters and the centre distance, including the wrap angles. The app uses the exact formula and shows the common approximation alongside it.
- Which GT2 belt length should I buy?
- Timing belts only come in whole teeth. Enter your pulleys and target centre distance, and the app lists the nearest belts with the centre distance each one gives.
Free on Google Play, supported by ads. Read the Pulley & Belt Calculator privacy policy. Questions or a bug? Write to support@tahatec.com.
