FabCalc vs SM Offset

The flat pattern calculator your fab shop needs — cylinders, cone gores, duct wraps, and more. Fully offline. No account. No ads. Stop laying out cone gores by hand on the table. Stop guessing developed length on a duct wrap. FabCalc generates shop-ready flat pattern drawings and 1:1 DXF files for common fabricated shapes. WHAT'S INSIDE • Cylinder wrap — full shell and partial segments • Half-pipe sleeve — 180° cylinder segments • Cone / frustum gore — annular sector with slant length and arc development • Rectangular duct wrap — four-panel strip with bend lines and bend allowance • Live 2D preview — cut profile, bend lines, roll direction, dimensions • DXF export — AutoCAD R12 ASCII, layered (CUT, BEND, ROLL, TEXT), 1:1 scale • PDF job sheet — drawing, inputs, calculated values, notes • Saved jobs — reopen and edit patterns locally WHO IT'S FOR Fabricators, sheet metal workers, pipe fitters, boilermakers, plasma/laser operators, and shop owners who need accurate flat patterns without desktop CAD. FREE vs PRO Free forever: all shape inputs, live preview, calculated values, warnings, and DXF cut-file export. Pro unlocks PDF job sheets and unlimited saved jobs. One-time purchase or subscription. Subscriptions auto-renew until cancelled. Manage in your Apple ID Subscription Settings. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://doublevision.company/privacy NO ACCOUNT. NO ADS. NO DATA COLLECTION. FabCalc works on the layout table, at the plasma table, in the truck. Everything runs locally.

SM Offset is a field calculator built for sheet metal workers, HVAC fabricators, and pipefitters who need exact offset math without the guesswork. Punch in your numbers and get the cut length, arc lengths, elbow centerline, and total offset length, all in real tape-measure fractions. Built for the shop floor and the jobsite, it works 100% offline. No signal, no problem. ROUND • Two-elbow offset — cut joint, elbow takeout, and arc length for a flat offset • Rolling offset — rise and roll combined into one true offset, with cut length to match • Rolling ninety — turn 90° while offsetting, with field-validated math RECTANGULAR • Duct fitting offsets from width, throat radius, and fitting angle • Standard angles (11.25°, 22.5°, 30°, 45°, 60°, 90°) or your own custom angle • Live results: cut joint, elbow centerline length, and exact offset length WHY TRADES TRUST IT • Every formula is cross-checked two ways • Results in real fractions, not ugly decimals • Fast, dark, glove-friendly interface Whether you're laying out ductwork in the shop or solving an offset on the roof, SM Offset gives you numbers you can cut to.