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Formulas, charts, quick calculators and tool guides for journeypersons and apprentices. Built for your phone, on the job.

Free with an account11 topics45 items31 calculators

Shop math and conversionsAll tradesFraction to decimal to mm chart, unit conversions for length, pressure, torque and temperature, right-triangle trig, area, volume and percent, with quick calculators.Speeds and feedsMachinist, MillwrightRPM from cutting speed (imperial CS × 4 ÷ D, metric CS × 1000 ÷ πD), typical HSS cutting speeds and milling feed rate, with calculators.Tap drill chartMachinist, MillwrightTap drill sizes for common UNC, UNF and metric coarse threads (about 75% thread), plus the tap drill formula and a calculator.Pulleys, gears and beltsMillwright, MachinistPulley and gear speed formulas (D1 × N1 = D2 × N2), drive ratio and open-belt length, with calculators.Shaft alignment basicsMillwrightShaft alignment basics for pumps and motors: offset and angular misalignment, soft foot, rim and face dial readings, and correction by similar triangles.Bolts, torque and fitsMillwright, Machinist, Heavy Equipment TechnicianSAE Grade 2, 5 and 8 and metric 8.8, 10.9 and 12.9 bolt markings and strengths, the T = K × D × F torque relationship, and fits and tolerances basics.Rigging and hydraulicsMillwright, Ironworker, Crane OperatorSling angle load factors and load per leg (load ÷ (legs × sin angle)), basic hitch capacities, steel weight estimates and hydraulic cylinder force (F = P × A).Electrical formulasConstruction Electrician, Industrial ElectricianOhm's law and the power wheel, series and parallel resistance, voltage drop from conductor resistance, single- and three-phase power and transformer ratios, with calculators.Conduit bending basicsConstruction Electrician, Industrial ElectricianConduit offset multipliers and shrink by bend angle, 3-point saddle marks and an offset calculator for EMT and rigid conduit.Kitchen math and food safetyCookRecipe scaling factor, yield percentage and edible-portion cost, °C and °F, volume and weight notes, baker's percentage, and danger-zone and cooling rules for cooks.Carpentry, pipe and weld basicsCarpenter, Plumber, Steamfitter/Pipefitter, WelderStair rise and run, rafter length by Pythagoras, board feet, rolling offsets, pipe grade and slope, and the parts of a weld symbol, with calculators.

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