Work out spindle output instantly with clear inputs, formula shown and shareable results.
Ring frame delivery speed is spindle rpm divided by twist per inch, and twist per inch is the twist multiplier times the square root of the English count. Converting delivery length to weight through the count gives output per spindle hour, which multiplied by spindles and hours gives mill production.
Twist and delivery
TPI = twist multiplier x sqrt(Ne); delivery (inch/min) = spindle rpm / TPI
Production
Weight = delivery length x tex; tex = 590.5 / Ne
Every turn of twist requires one spindle revolution, so at fixed spindle speed more twist means less yarn delivered. Twist is set by yarn strength and hand requirements, not by productivity.
3.2-3.6 for weft and knitting yarns, 3.8-4.3 for warp, and above 4.5 for voile and crepe. Higher multipliers give stronger, harder yarn at lower output.