Lead Screw Lead
Compute the lead of a ball screw or power screw, Lead = pitch · number of starts, the linear distance the nut travels per full turn of the screw. On a single-start screw the lead equals the pitch; with multiple starts the lead increases proportionally, allowing more linear speed at the same rotation. The basis of rotation-to-displacement conversion in CNC and linear actuators. Enter the pitch and the number of starts.
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Lead screw lead
On a lead screw (a power screw or a ball screw), it is important to tell pitch apart from lead. The pitch is the distance between neighboring threads; the lead is how far the nut travels per full turn: lead = pitch · number of starts. On a single-start screw, lead equals pitch. Multi-start screws (two or three parallel helices) advance 2× or 3× farther per turn while keeping the threads fine and strong — the usual choice when high linear speed is wanted without spinning the screw too fast. The lead is the factor that converts motor rotation into linear travel: dividing the desired stroke by the lead gives the number of turns. It underpins the design of CNC machines, presses and actuators. Enter the pitch and the number of starts.
Related Tools
Stepper Motor Resolution
Compute the angular resolution of a stepper motor, R = 360°/(steps per revolution · microsteps), the smallest angle the shaft can position. A common 200-step motor (1.8°/step) with 16 microstepping reaches 0.1125° per microstep — 3200 positions per revolution. Microstepping smooths motion and raises resolution, though it lowers the holding torque per microstep. Enter the steps per revolution and the microstepping factor.
Machining Spindle Speed
Calculate the spindle speed (RPM) needed in machining, n = (1000·Vc) ÷ (π·D), from the desired cutting speed Vc (m/min) and the diameter D (mm — workpiece in turning or tool in milling). It is the inverse of the cutting-speed calculation, and the most used on the shop floor: the operator knows the material, picks the recommended cutting speed from tables, and must convert it to the rpm to set on the machine. The relation reveals a key point: for the same cutting speed, SMALLER-diameter parts or tools require HIGHER rpm (and vice versa). So turning a part of varying diameter (facing, tapers) at constant cutting speed requires continuously varying the rpm — done automatically by CNC lathes (G96, constant surface speed), while on conventional lathes the operator adjusts by ranges. Getting rpm right is essential for tool life, finish and safety (excessive rpm on large parts creates dangerous centrifugal forces). Enter the cutting speed and the diameter.
Bearing Mean Diameter
Calculate a bearing's mean (pitch) diameter, d_m = (D + d) ÷ 2, from the outer diameter D (mm, of the outer ring) and the inner diameter d (mm, of the bore, fitting the shaft). The mean diameter is the average of the bore diameter (seating on the shaft) and the outer diameter (seating in the housing), and roughly represents the diameter of the CIRCLE described by the rolling-element centers (the pitch diameter). It is a fundamental bearing geometric parameter, used in several calculations: in the SPEED FACTOR n·d_m (governing limit speed and heating), in estimating the rolling-element peripheral velocity, in the characteristic defect frequencies (used in vibration analysis for diagnosis — the ball-pass frequencies of inner/outer race, BPFI/BPFO, depend on d_m), and in the cage rotation speed. The mean diameter is the compact way to characterize a bearing's 'size' for these kinematic and dynamic calculations, without needing the internal details (number and diameter of rolling elements, contact angle). The outer D and inner d diameters are the basic catalog dimensions of any bearing (with the width), and d_m derives directly from them. Enter the outer and inner diameters.
Stepper Motor Speed
Calculate the rotation speed of a stepper motor, RPM = (pps × 60 × step angle) ÷ 360, from the pulse frequency pps (steps per second) and the motor's step angle (degrees per step). The result, in revolutions per minute, relates the command frequency sent to the driver with the actual shaft speed. Stepper motors lose torque at high speeds, so there is a practical maximum rotation. It is essential for programming axis speeds in 3D printers, CNC and automation. Enter the pulse frequency and the step angle.
Kanban Lead Time Average Days
Estimates average Kanban lead time by summing queue time and cycle time per task.
Tooth Thickness at Pitch Circle
Calculate the tooth thickness measured at the pitch circle of a standard gear, s = (π·m) ÷ 2, from the module m (mm). In a standard (uncorrected) gear, the circular pitch (the distance from one tooth to the next, along the pitch circle) is p = π·m, and it splits equally between the TOOTH (the solid part) and the SPACE (the gap between teeth): half each, hence s = π·m/2. This equality between tooth thickness and space width is what lets two standard gears of the same module mesh perfectly, with one's tooth fitting the other's space with proper clearance. Tooth thickness is a fundamental parameter: it sets the tooth STRENGTH (thicker teeth resist bending more) and the mesh backlash. In CORRECTED gears (with profile shift, used to avoid interference in small pinions, adjust center distance or balance pinion-gear strength), the pitch-circle tooth thickness DIFFERS from π·m/2 — it increases in a positively corrected pinion (strengthening it) and decreases in the gear. Measuring tooth thickness (by the chordal method, with a gear-tooth caliper, or over pins) is a classic gear quality-control check. Enter the module.
The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.