Engineering reference charts.
Lookup tables for working engineers. Torque values by bolt grade, hardness across every common scale, surface finish achievable by each manufacturing process. Cited values per ISO and ASTM standards. Free, no signup.
Live charts
Bolt torque chart by grade and lubrication
Metric (M5–M30) and imperial (1/4"–1") bolt torque tables for ISO grades 4.8 / 5.8 / 8.8 / 10.9 / 12.9 and SAE Grades 2 / 5 / 8. Dry, lubricated, and stainless variants. Computed from T = K × D × F per ISO 898-1.
Hardness conversion chart
Rockwell C, Rockwell B, Vickers, Brinell, Knoop, and approximate tensile strength conversions per ASTM E140. Steel ranges, non-ferrous metals, and Indian engineering grades (EN8, EN24, EN36, EN9, EN353) production hardness.
Surface finish by process
Typical and best-achievable Ra values for every major process — casting, forging, milling, turning, drilling, grinding, honing, lapping, EDM, electropolishing. ISO N grades (N1–N12) and Ra-to-Rz conversion factors.
In progress
Drill size chart — tap drill, clearance, ANSI/ISO
Tap drill sizes for every metric and imperial thread, clearance drill sizes by fit class, ANSI-letter and number drill cross-reference. Includes fine-thread variants.
ISO 286 fits chart — H7/g6, H7/h6, H7/k6, H7/n6, H7/s6
Hole and shaft tolerance values for every common fit class. Clearance, transition, and interference fits with worst-case clearance/interference per ISO 286-1.
Aluminium alloy properties comparison
Tensile, yield, hardness, density, machinability, weldability, corrosion resistance for 1100, 2024, 5052, 6061, 6063, 7075 — the most-used wrought aluminium alloys in Indian manufacturing.
Steel grade comparison — Indian, SAE, ISO
Cross-reference for EN8, EN9, EN19, EN24, EN36, EN353 vs SAE 1045, 4140, 4340, 8620, ISO equivalents. Heat treatment, hardness, applications, machinability.