#maker

3D-printing filament maths as an API, computed locally and deterministically. The length-weight endpoint converts between the length and the weight of a spool of filament from its diameter (1.75 mm or 2.85 mm) and material density, using weight = (π/4·d²·length)·density — so one metre of 1.75 mm PLA weighs about 2.98 g, a standard 1 kg PLA spool holds roughly 335 m, and the same weight of the lighter ABS gives about 400 m. The cost endpoint computes the filament cost of a print from the weight or length used and the price per kilogram, and the spool-remaining endpoint turns a remaining-weight measurement (weigh the spool, subtract the empty-spool weight) into the remaining length so you know whether a job will finish. Built-in densities cover PLA, ABS, PETG, TPU, nylon, ASA, PC, HIPS, PVA, wood-fill and carbon-fibre blends, or supply your own. Diameters are in millimetres, lengths in metres and weights in grams. Everything is computed locally and deterministically, so it is instant and private. Ideal for 3D-printing, maker, print-farm, slicer-plugin, prototyping and STEM-education app developers, filament-usage and print-cost tools, and workshop software. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is filament geometry and cost; for tank or material volume use a volume API.

api.oanor.com/filament-api

Capacitor maths as an API, computed locally and deterministically. The energy endpoint computes the stored energy and charge of a capacitor from any two of the capacitance, the voltage and the charge — E = ½CV² = ½QV and Q = CV — in joules, millijoules and coulombs. The charging endpoint models the RC charging and discharging transient: the time constant τ = RC, the voltage at a given time, V(t) = Vs(1 − e^(−t/RC)) when charging or V(t) = V₀·e^(−t/RC) when discharging, and the percent charged, or — given a target voltage — the time to reach it; a capacitor reaches about 63 % of the way in one time constant and over 99 % in five. The combination endpoint computes the total capacitance of capacitors in series (1/C = Σ1/Cᵢ) or parallel (C = ΣCᵢ). Capacitance accepts farads or the handy µF/nF/pF units. Everything is computed locally and deterministically, so it is instant and private. Ideal for electronics, maker, embedded and circuit-design app developers, power-supply and timing tools, and electronics education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is capacitor maths; for AC reactance and resonance use a resonance API and for LED resistor sizing an LED-resistor API.

api.oanor.com/capacitor-api

LED current-limiting-resistor maths as an API, computed locally and deterministically. The resistor endpoint sizes the series resistor for a single LED, R = (V_supply − V_forward) / I, and returns the resistor power dissipation (I²·R), the LED power, a recommended resistor wattage rating and the nearest E12 standard value (rounded up so the LED current stays at or below the target). The series endpoint sizes the one shared resistor for several LEDs wired in series, where the forward voltages add, R = (V_supply − n·V_f) / I, and flags when the supply is too low for the string. The parallel endpoint gives the per-LED resistor for LEDs in parallel (each needs its own) and the total current the supply must deliver. Currents are entered in milliamps. Everything is computed locally and deterministically, so it is instant and private. Ideal for electronics, maker, Arduino and hardware app developers, LED and lighting-circuit design tools, and electronics education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is LED resistor sizing; for general Ohm's law and reactance use an Ohm's-law API and for AWG wire properties use a wire-gauge API.

api.oanor.com/ledresistor-api