Step by step, formulas and common mistakes of sheet metal layout: cone, lobster back bend, square to round and the neutral axis. Each guide links to the part that calculates it.
How to lay out a truncated cone (frustum) on plate: the formula for the slant height, both sector radii and the sector angle, the thickness offset on the neutral axis, marking out with a trammel and the mistakes that stop the seam closing.
Lobster back bend calculator and formula: the half-mitre, the cut height at every element, the ordinate table, how many plates to cut and how to assemble.
Pipe saddle calculator and formula for a pipe-to-pipe branch at 90 and 45°: the length of every element, the ordinate table and the hole in the main.
How to develop a square or rectangle to round transition by triangulation: the true lengths, the chord of the circle, the order in which the triangles are built, the worked example and the mistakes that stop the part closing.
What the neutral axis is, why every development is worked on it, what π × D leaves at the seam, how the offset shrinks on a cone, and the K-factor table for press bends.
Plate-shop vocabulary in two lines: shell, gore, saddle cut, crotch cut, hopper, neutral axis, trammel, template and thirty more, each tied to the part that uses it.
Who operates Planichapa and how each of the 52 flat patterns is checked: constructible triangles, zero weld error, plate area against solid area, figures published by third parties and the neutral axis on every part. And the mistakes we have already fixed, with dates.
LITIO2 is no longer sold or supported, its own site says. A browser alternative: 52 parts on the neutral axis, mm or inches, 3D, PDF and DXF. Unlimited calculations free.
How to mark out a mitre cut on a pipe or shell at 45° or any angle: the sine-wave formula, the worked ordinate table, the paper template and the two-cut elbow.
A Plate 'n' Sheet alternative in the browser: 52 parts on the neutral axis, 3D, PDF and DXF. Unlimited calculations free; one-off 12-month purchase. What changes and what doesn't.
Steel plate weight calculator and table per m² and ft², from 20 gauge to one inch and 2 to 25 mm, the formula for any thickness and the stock plate sizes.
Pipe ovality calculator and formula, (Dmax − Dmin) / D × 100: the two definitions, a worked example, the ASME B31.3 limits for bends and how to measure it.
What to check in pattern development software: parts, neutral axis, DXF and PDF, platform, pricing. Where Planichapa, CALDsoft, Plate 'n' Sheet and the apps differ.
Concentric vs eccentric reducer: where each goes in pipework and hoppers, why one is a trammel sector and the other triangulation, and the offset cone that does both.
Roller chain sizes in one chart: pitch and roller diameter of ANSI 25 to 160, ISO 606 05B to 24B, motorcycle and bicycle chain, and how to tell them apart.
How to work out a roller chain sprocket: pitch, outside and root diameter, the caliper reading for odd teeth and the ISO 606 tooth, with an example and a chart.
How to lay out a bolt circle (PCD): the angle between holes, the x and y of each hole, the chord for the dividers and a chord chart for 3 to 24 holes.
How to size a roller chain drive: the sprocket ratio and output speed, the chain length in links, the real centre distance and the wrap, with an example.
Screw flight calculator and formula: the ring radii and the wedge of the flat blank of a screw conveyor (auger) flight, a worked example and forming notes.
Plate rolling calculator: the blank length to roll a cylinder from its inside, outside or mean diameter, the shell weight, how many stock plates, a chart and the formula.
Free tube notching and coping template generator: type the two tube sizes, the angle and the offset, and print the fishmouth template at full size on A4 or Letter, with a table of heights.
Dished head calculator for Klöpper, Korbbogen, ASME F&D, 2:1 elliptical and hemispherical heads: inside depth, overall height, volume, blank diameter and weight, with the formulas.
Free cone template generator: type the two diameters and the height, and print the cone at full size on A4 or Letter for a hopper, funnel or reducer.
Pie cut calculator in mm or inches: tube OD, centreline radius, bend angle and number of pies give the saw angle, each pie's length and a 1:1 template.
Square to round duct transition layout in inches: centred, offset or flat on one side, with gauge, fractions, a full-size Letter template and DXF.
Printable pipe templates for NPS 1/2 to 12: tee saddle, 45° lateral and mitre at full size on Letter, on the real outside diameter: 2 in pipe is 2.375 in.
Register boot layout in inches: the boot from a rectangular register to a round duct coming in from the side or from below, what to measure, the template.
Plenum box and supply plenum transition layout in inches: which page draws the sides, the offset and the round outlet, and what you still add by hand.