Machinist shop math

    The everyday shop math — tolerances, finishes, hardness, triangles and conversions — in one place next to your speed and feed numbers.

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    Calculators

    Tolerance CalculatorMin/max dimensions, bilateral tolerance stackup, and pass/fail.Surface Finish CalculatorTheoretical Ra from feed rate and tool nose radius.Hardness ConverterConvert between HRC, HRB, Brinell, Vickers scales.Right Triangle SolverSolve any right triangle from two known values.Unit ConverterLength, weight, pressure, temperature, torque, and speed.Cycle Time EstimatorEstimate total cycle time from cutting parameters.

    What it covers

    • Tolerance stackup with pass/fail
    • Theoretical Ra from feed and nose radius
    • HRC, HRB, Brinell and Vickers conversion
    • Right-triangle solver with live diagram

    Common questions

    How is theoretical surface finish calculated?
    Ra ≈ feed² ÷ (32 × nose radius), using the same units for both.

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