Assembly Instructions Glossary: Parts, Tools and Symbols Explained

Why a glossary helps

Assembly instructions use a small vocabulary of parts, tools and symbols again and again. Once you know them, most manuals become much easier to read. This glossary covers the terms you are most likely to meet in furniture, fitness equipment, bikes, grills and toys.

Fasteners and fittings

• Cam lock: a round metal fitting set into a panel. You push a cam bolt into the next panel, then turn the cam about half a turn to pull the two tight together.
• Cam bolt: the metal pin that screws into one panel and is gripped by the cam lock in the other.
• Dowel: a short, ridged wooden peg that lines two panels up. It locates them; on its own it doesn't hold them tight.
• Confirmat screw: a thick, coarse screw that joins two particle-board panels at a right angle.
• Barrel nut: a small cylinder with a threaded hole across it, used with a long bolt to make a strong joint, common in beds and cribs.
• Washer: a flat ring under a bolt head or nut that spreads the load. Spring washers help stop a bolt working loose.
• Lock nut: a nut with a nylon insert that resists loosening from vibration, common in fitness equipment and bikes.
• Wall plug (anchor): the insert that lets a screw grip a wall. The right type depends on the wall.

Tools

• Allen key (hex key): the L-shaped tool that comes in most flat-pack boxes, for screws with a six-sided hole.
• Phillips and flat screwdrivers: for cross-head and slotted screws. Using the wrong size strips the head.
• Torque wrench: a wrench that tightens to a set force. Bike and fitness manuals often give torque values in newton-metres (Nm).
• Rubber mallet: for tapping dowels and panels into place without marking them.

Parts of the manual

• Parts list: the page that names every panel and component, usually with a letter or number.
• Hardware list: the page that shows every screw, bolt and fitting, often at actual size, with how many of each are in the box.
• Exploded view: a drawing with the parts pulled apart along the lines where they fit together.
• Callout (magnifier circle): an enlarged detail of a small area, showing something you must get right.
• Step number: the order of work. Later steps often depend on earlier ones being done exactly.
• Orientation mark: a symbol or label that shows which way a panel faces, such as the finished edge or the side with pre-drilled holes.

Symbols you'll see

• Arrow: the direction a part moves, or which way to turn.
• Two people: this step needs a second person, usually for weight or to hold parts square.
• Cross over a drawing: don't do it this way.
• Tick next to a drawing: this is the right way.
• Curved arrow: turn the part, for example about half a turn on a cam lock.
• Telephone or speech bubble: contact the maker instead of forcing it, often shown near the parts list.

Safety terms

• Anti-tip kit (tip-over restraint): a strap or bracket that fixes tall furniture to the wall. The US Consumer Product Safety Commission's Anchor It! campaign explains why it matters.
• Two-person lift: the part is too heavy or awkward for one person.
• Leak test: for gas grills, the soapy-water check that the gas connections are sealed before first use.

When the words aren't enough

Some steps are hard to follow on paper however well they are drawn, especially where a part has to turn or slide into place. That is where an assembly video helps: motion shows what a still drawing can only suggest. For practical tips, see Flat-pack tips and How to assemble furniture.