Cross-Trade Utilities

Tools in this group

• Unit Converter - Length, area, volume, mass, force, pressure, temperature, energy, power, flow, electrical.
• Material Cost Estimator - Total cost from price per unit and quantity.
• Markup and Margin - Selling price from cost and target.
• Time and Materials - Total billable from hours, rate, and material cost.
• Sales Tax - Tax and total by state.
• Tip Out - Per-person split for crews.
• Loan Payment - Monthly payment, total interest, and 12-month amortization.
• Upgrade ROI / Payback - Simple payback and 10-year NPV at user-supplied discount rate.
• Mileage and Fuel Cost - Gallons, fuel cost, and IRS reimbursement from miles and MPG.
• Overtime Hours - Regular, overtime, and double-time pay breakdown.
• Per-Diem (GSA) - Federal per-diem lodging or M&IE rate by state.
• Geometry Pack - Circle, ellipse (Ramanujan), hexagon, sphere.
• Dilution / Mixing Ratio - Concentrate volume and diluent volume from target strength.
• Slope from Digital Level - Bidirectional between degrees, percent, and inches per foot.
• GPS Distance (Haversine) - Great-circle distance and initial bearing between two coordinates.
• OSHA Trench Sloping - Maximum slope ratio per soil class A/B/C and benching geometry.
• NIOSH Lifting Equation - RWL and Lifting Index per the public NIOSH 1991 multipliers.
• Heat Stress (WBGT and Heat Index) - Heat index, WBGT estimate, and OSHA-style work / rest cycle.
• Wind Chill Exposure - NWS 2001 wind chill formula and frostbite-time exposure curves.
• Ladder Placement Angle - Base distance for the 4:1 rule and pass/fail at 75.5 deg.
• Pulley System Mechanical Advantage - Theoretical and actual MA across fixed/movable/block-and-tackle rigs.
• Ramp Slope (ADA) - Slope ratio, percent, and pass/fail against 1:12 maximum.
• Rainwater Harvesting Yield - Annual gallons from catchment area, rainfall, and collection efficiency.
• Daily Multi-Job Timesheet - Hours per job with overtime split, gross pay, and reimbursable miles.
• Fall Protection Clearance - Required clearance below anchor = free-fall + decel + worker height + harness stretch + safety factor; pass/fail vs actual clearance to next lower level.
• OSHA 1910.95 Noise Dose and TWA - Multi-row workshift dose with the OSHA 5 dB exchange formula, 8-hr TWA, and pass / fail against the 85 dBA action level and 90 dBA PEL.
• Vehicle Load Distribution - Front and rear axle weights with GVWR / GAWR flags.
• Pump Total Dynamic Head (TDH) - Total dynamic head from static lift, static discharge, and Hazen-Williams suction / discharge / fittings friction, with a pump-curve operating point.
• Hydraulic Cylinder Force and Speed - Cylinder force, extend / retract speed, oil per stroke, and cycle time from bore, rod, pressure, and pump flow (NFPA T2.13.7).
• V-Belt Sheave and Drive Sizing - Speed ratio, driven pitch diameter, belt length, service-factor design HP, and a belt-count planning estimate (ANSI/RMA IP-20 / IP-22).
• Gear Ratio and RPM Cascade - Per-stage and overall ratio, output RPM, and output torque across up to four gear stages with a per-stage efficiency.
• Rolling Offset - True offset, travel, and run advance for a pipe or conduit rolling offset.
• Fitting Take-Out Cut Length - Cut length of pipe between two fittings from center-to-center or face-to-face, with take-out and thread make-up shown.
• Multi-Piece Miter Elbow Layout - Per-cut miter angle, weld count, and cutback for an n-piece lobster-back miter elbow.
• Pipe Wraparound Template Ordinates - Markback ordinate table for wrapping a template to scribe an angled pipe cut.
• Flange Bolt-Up Torque - Target preload and short-form torque (T = K*D*F) per bolt plus the cross/star tightening sequence for a bolted flange joint.
• Center of Gravity from Two Scales - Total weight, CG distance, and the load split from a two-point weigh by moment balance (ASME B30.9 / ITI rigging).
• Insulated Pipe Rack Spacing - Center-to-center spacing, total bundle width, and rack fit for parallel insulated pipe runs from OD, insulation thickness, and clearance (ASTM C585).
• Bolt Circle Layout - Hole coordinates (X, Y) for a circle of N evenly spaced holes from a bolt-circle diameter, start angle, and center, plus the angular spacing and adjacent center-to-center chord (first-principles circle-of-holes trigonometry).
• Decimal to Fraction - Tape-measure math: round a decimal inches value to the nearest 1/8, 1/16, 1/32, or 1/64, reduce the fraction to lowest terms, break it into feet-inches, and report the rounding error (first-principles arithmetic).
• Sine Bar Angle Setup - Precision angle setup: the angle from a gauge-block stack on a sine bar (theta = arcsin(H / L)), or the stack height for a target angle (H = L x sin(theta)), for any roll-center length (first-principles sine-bar trigonometry).
• Thread Pitch and Lead - Thread pitch, lead, and 60-degree sharp-V height for UN/UNC/UNF inch (pitch = 1 / TPI) and ISO metric (pitch in mm) threads: lead = pitch x starts, H = pitch x sqrt(3)/2 (first-principles 60-degree thread geometry).
• Bolt Proof, Yield, and Tensile Load (SAE J429) - The fastener ceiling bolt-torque assumes but never shows: strength acts on the tensile stress area At = 0.7854 x (D - 0.9743/n)^2 (about 15% under the nominal shank, so a nominal-area guess over-predicts), and the grade -- read from the head markings -- sets every number. A 1/2-13 Grade 5 bolt (At 0.1419 in^2) has a 12,060 lb proof load, 17,030 lb tensile, and a 9,045 lb recommended clamp (75% of proof); the identical bolt in Grade 8 jumps to 17,028 lb proof and 12,771 lb clamp. Grade 2: 55/57/74 ksi; Grade 5 / A325: 85/92/120; Grade 8 / A490: 120/130/150. A design aid; the joint design, torque method, and preload requirement govern.
• Three-Wire Thread Measurement - Three-wire measurement over a 60-degree thread: best wire W = 0.57735 x pitch, acceptable wire range, and measurement over three wires M = E + 3W - 1.51553 x pitch from the user-supplied pitch diameter (first-principles thread geometry).
• Punch / Shear Force - Punching force from the cut perimeter (round, rectangular, or entered directly), material thickness, and shear strength: F = perimeter x T x shear strength, in pounds and US tons, with an estimated stripping force (first-principles shear).
• Interference Shrink-Fit Temperature - Heating temperature (or chilling temperature) to open an interference fit enough to assemble a hub, bearing, or bushing by hand, from the thermal-growth relation delta_dia = alpha x dia x delta_T (steel alpha 6.5e-6/degF). Sizes only the assembly temperature; a separate Lame contact-pressure check governs the holding capacity.
• Interference Press-Fit Pressure and Holding Force (Lame) - The Lame holding-force check shrink-fit defers: the diametral interference produces a contact pressure p = (E x interference / D) x (Do^2 - D^2)/(2 Do^2), an axial holding force = p x pi x D x length x friction, and a hub bore hoop stress = p x (Do^2 + D^2)/(Do^2 - D^2). A 2 in shaft, 0.002 in interference, 4 in hub, steel, mu 0.12, 3 in engagement grips at 11,250 psi -> 25,447 lb, with 18,750 psi bore stress (below yield); a thin 2.5 in hub drops to 5,400 psi -> 12,215 lb (under half) while the bore stress climbs to 24,600 psi. Too much interference bursts the hub. Same-material solid-shaft model; the materials and assembly method govern.
• Rolled Plate Blank Length - Developed flat blank length to roll plate into a cylinder or ring at the neutral axis: L = pi x neutral-diameter, with neutral axis k x T from the inside (D_neutral = OD - 2T(1-k) = ID + 2kT; default k = 0.5 mid-thickness gives pi x (OD - T)) (first-principles arc-length geometry).
• Tolerance Stack-Up: Worst-Case and RSS - Worst-case tolerance = sum of the half-widths; statistical RSS = sqrt(sum of squares), always tighter. Three dims at +/-0.005 -> +/-0.015 worst-case, +/-0.00866 RSS; a 0.020 gap fits 0.005-0.035 (WC) or 0.0113-0.0287 (RSS). The RSS benefit widens as the chain grows. A design aid; the drawing tolerances govern.
• Cone Flat-Pattern Development (Radial Line) - Flat pattern of a right cone: slant L = sqrt(r^2 + h^2), sector radius = L, sweep = 360 r / L. R 6 in, h 8 in -> L 10 in, 216-degree sector; a taller R 6/h 16 cone -> 17.09 in slant, a narrower 126-degree sector. Add seam and bend allowance. A layout aid; verify against a test piece.
• Tank Volume (Dipstick) - Partial liquid volume of a horizontal or vertical cylindrical tank from a depth (dipstick) reading: horizontal uses the circular-segment area R^2 x acos((R-h)/R) - (R-h) x sqrt(2Rh-h^2) times length, vertical uses pi x R^2 x depth, reported in US gallons, liters, and cubic feet with percent full (first-principles geometry, flat ends).
• Linear Interpolation - Read a value between two known points off a chart or table: y = y1 + (x - x1) x (y2 - y1) / (x2 - x1), with the slope and an extrapolation flag when the query falls outside the two points (first-principles linear interpolation for derating, pump-curve, steam, psychrometric, and calibration tables).
• Circular Arc Layout - Radius, arc length, and central angle of a circular arc from a measured chord (span) and rise (sagitta / middle ordinate) at midspan: R = (chord^2/4 + rise^2) / (2 x rise), central angle = 2 x acos((R - rise)/R), arc length = R x angle - the everyday layout question for an arch, curved trim, sheet-metal radius, or road curve (first-principles circle geometry).
• Circle Through Three Points - Center and radius of the circle through three measured points on an arc (the circumcircle - the inverse of bolt-circle): center = circumcenter of the triangle, radius = distance from the center to any point, with the diameter and circumference. Recovers a curve's radius from three field points when the chord and midspan rise cannot be measured directly (first-principles coordinate geometry).
• Regular Polygon Miter and Layout - Saw miter and piece sizing to build any N-sided frame (octagon column wrap, hexagon planter, picture frame, segmented ring): each joint is mitered at 180/N degrees off square, the interior angle is (N-2) x 180/N, and the side relates to the across-flats width (s = flats x tan(180/N)) and across-corners diameter (s = corners x sin(180/N)), with perimeter and area (first-principles regular-polygon geometry; square 45, hexagon 30, octagon 22.5).
• Equal Spacing Layout - Evenly space balusters, pickets, studs, shelf pins, or layout marks in a run: N items of width w have N+1 equal gaps of (run - N x w)/(N+1) and a center-to-center pitch of gap + w. Solve for the count from a maximum gap (the smallest N with gap at or below the limit, e.g. the IRC 4-inch-sphere guard rule) or the gap from a desired count, with the mark positions (first-principles layout arithmetic).