Engineering tools
Free calculators, built from real production work
A growing set of practical engineering tools, built from the same calculations we use ourselves on the shop floor — not generic textbook reference charts. Free to use, with full disclaimers on each tool.
Trapezoidal Coiling Calculator
Calculates the trapezoidal wire preform dimensions needed to produce a finished rectangular-section coiled ring, with springback, Poisson and thermal corrections.
Open calculator → Spring designSpring Rate Calculator
Spring rate, deflection and stress checks for compression, extension and torsion springs from standard wire and coil geometry.
Open calculator → Wire productionWire Drawing Calculator
Area reduction, true strain and draw stress for round wire drawing — single-pass check or a full multi-pass schedule with annealing points flagged.
Open calculator → Wire productionWire Profile Rolling Calculator
Round stock to keystone (trapezoidal) section — verified area, reduction and elongation relationship, with bevel/chamfer corrections for finished retaining ring wire.
Open calculator → MachiningThread Root Relief & Dual-Index Calculator
Real thread dimensions for Metric/UN and Whitworth threads, plus a dual-index pass solution for when your insert's nose radius is smaller than the standard root radius — corrects depth without over-cutting.
Open calculator → Retaining ringsRetaining Ring & Circlip Calculator Suite
Seven calculator modules covering grooved axial rings (DIN 471/472), snap rings, grip rings, radial rings, support washers, assembly stress verification and groove checking — built from generalised retaining-ring design relationships and hands-on ring production experience.
Open calculator suite → Press toolingPiercing Punch Force & Buckling Calculator
Piercing force, punch stress and Johnson–Euler buckling capacity, with the maximum unsupported length for straight or stepped punches. Covers round, rectangular, obround and custom tips, tool steel, HSS and carbide punch materials, minimum punch size and stripping force.
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