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 for sheet metal workers, HVAC fabricators and pipefitters, built by a working sheet metal tradesman. Every calculator is free, it works with no signal, and answers come out in real tape-measure fractions. ROUND • Two-elbow offset: cut joint, travel and multiplier for a flat offset • Rolling offset: rise and roll combined into one true offset, with the cut length to match RECTANGULAR • Radius elbows: two radius elbows plus a straight joint, with cut joint, travel and multiplier • Mitered offset: square-throat elbows, with cheek length and miter setback • Offset in a length: drop in the run you have, and the app works out the angle TOOLS • Duct resizer: something in the way? Shrink a side, keep the airflow • Equivalent duct: round to rectangular and back (ASHRAE equal-friction and equal-area) • Fraction ⇄ decimal, right triangle (any two values), arc length SEND IT TO THE CREW • Share any offset result as a text, with every size, angle and cut length WHY TRADES TRUST IT • Every offset is exact trig, cross-checked two independent ways • A live drawing of the fitting as you type • Fractions to 1/16" (or 1/32"), decimals, or metric • Your shop's connection allowance, set once • Recent calculations saved automatically • Fast, dark, glove-friendly 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.