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Calculate welding amperage from material thickness, joint type, and electrode size. Set current for MIG, TIG, and stick welding on steel and aluminum.
Calculate weight of metal bar, plate, tube, and sheet stock from dimensions and alloy density. Supports steel, aluminum, copper, and common alloys.
Find the correct tap drill size for threading from nominal diameter and thread pitch. Supports metric, UNC, UNF, and pipe thread standards.
Pitch is the distance between adjacent thread crests. TPI (threads per inch) is the inverse of pitch in inches. Metric pitch is stated directly in millimeters.
Pitch (in) = 1 / TPI; TPI = 1 / Pitch (in)Major diameter is the outer crest diameter (nominal bolt size). Minor diameter is measured at the thread root. For unified external threads, minor ≈ major − 1.0825 × pitch.
Minor (external) ≈ Major − 1.0825 × PitchMetric threads are designated M diameter × pitch (e.g., M10×1.5). If pitch is omitted, use the ISO coarse pitch standard for that diameter (M10 coarse = 1.5 mm).
Designation: M{major}×{pitch}Updated: July 2026
Measure 10 mm major diameter and 1.5 mm crest-to-crest spacing with calipers. Designation is M10×1.5. Compare against M10×1.25 fine pitch to confirm the correct tap and nut.
1/2-inch-13 UNC has pitch = 1/13 = 0.0769 inch (1.954 mm). Major diameter 0.500 inch; minor diameter approximately 0.417 inch for external threads.
M16×2.0 pitch on a lathe: one revolution advances 2 mm axially. Feed rate at 300 RPM = 300 × 2 = 600 mm/min for single-point threading pass.
M10 coarse is 1.5 mm pitch; M10×1.25 and M10×1.0 are common fine pitches. Always measure pitch — nominal diameter alone is insufficient for thread identification.
Pitch is measured between corresponding points on adjacent threads — crest to crest for external threads. Root-to-root measurement includes thread depth and gives incorrect pitch values.
Thread pitch defines how far a screw advances per revolution and determines mating compatibility, tap drill size, and thread strength. This calculator computes pitch, threads per inch, and major/minor diameters for standard metric and unified thread systems.