About PerBond

Most bonding problems aren’t about the glue itself — they’re about the small numbers around it. How much adhesive does this bond actually need? What’s the split for a 2:1 epoxy if I want 300 grams? Will this joint hold the load, and how long an overlap does it take? How much longer will it cure in a cold workshop? Each question is simple on its own, but working through all of them by hand, for every job, is where a straightforward bond turns into guesswork.

PerBond is built to take that arithmetic off your bench. Rather than long articles you have to read end to end, the site is organized around a handful of small, single-purpose calculators, each aimed at one part of a bond. The Adhesive Coverage Calculator turns a bond area and glue-line thickness — or a bead diameter and length — into a volume and an approximate mass, so you buy the right amount. The Epoxy Mix Ratio Calculator splits a two-part batch into Part A and Part B by weight or volume at any ratio, and warns when a batch is big enough to shorten pot life. The Bond Strength Calculator estimates the load a lap-shear joint can carry from its area and the adhesive’s shear strength, or the minimum area for a target load. The Cure Time Calculatoradjusts a base cure time for temperature using the rule that cure roughly halves for every 10 °C rise. The Coverage per Cartridge Calculator turns a cartridge volume into metres of bead or an area at a chosen film thickness. And the Lap Joint Designer sizes the overlap a single-lap joint needs to carry a load, with overlap-to-thickness guidance.

Beyond the calculators, the blog and learnsection cover adhesive selection, surface preparation, mixing and curing, and joint design — including the reasoning behind the numbers the tools produce. The museumis a separate, browsable collection with every entry, image, and fact drawn from Wikipedia and Wikimedia Commons; it’s there for the pleasure of looking, not as a bonding reference.

A few things worth stating plainly. PerBond is an independent site, not an adhesive manufacturer or retailer, and not affiliated with any adhesive brand or standards body. It is supported by advertising, which is how the tools stay free with no account required. Every result the tools produce — a coverage volume, a mix split, a strength estimate, a cure time, an overlap length — is a general estimate built on standard formulas and the numbers you enter, not a validated engineering design. Adhesive performance depends on the exact product, your surfaces and their preparation, cure conditions, and the loads and environment the joint will see, so where our estimate and the adhesive’s technical data sheet disagree, follow the data sheet — and have any load-bearing or safety-critical joint checked by a qualified engineer. If something looks off in a tool or an article, or there’s a calculator you wish existed, the contact page is the place to say so.