How to choose metal wire: annealed, galvanised or plastic-coated

For tying rebar you need annealed wire, a soft annealed iron wire that is easy to knot; for fencing, supports and outdoor work you choose galvanised or plastic-coated wire, which resists rust better. The thickness depends on the load: in the collection the diameter ranges from 0.4 mm for fine wires up to 4.5 mm for tensioning wires. To tension it you need a wire strainer or a turnbuckle, used without exceeding the load limit of the wire.

The types

• Annealed wire: annealed iron, soft, available in black, white or galvanised. It is the wire for rebar tying in building work, like the Mafi black annealed wire or the white annealed wire on reels.
• Galvanised wire: coated with zinc against rust, for outdoor use. There is also annealed and galvanised wire, like the Mafi galvanised annealed wire.
• Plastic-coated wire: wire with a plastic sheath, coloured (for example green), for fencing and outdoor supports.
• Steel, copper and brass wire: for special uses, thinner or with greater load resistance. The catalogue also includes soft florist's wire.
• Gabion stitching wire: for closing and joining gabion meshes.
• Wire strainers and turnbuckles: pull-type wire strainers, standard wire strainers, spring turnbuckles and dynamometric turnbuckles, plus universal handles for wire strainers. For example the Mass galvanised pull-type wire strainers.
• Small spools, coils and reels: the wire comes in coils and reels, in small sizes for tying and larger ones for continuous supplies.

How to choose by job

The features to look at

• Wire diameter (mm): in the collection you will find values from 0.4 mm, for light tying, to 1.0-4.5 mm for more demanding uses. The thicker it is, the stronger it is but the harder it is to bend.
• Material: annealed iron (annealed wire), steel, tropicalised steel, copper, brass. Annealed iron is soft and easy to knot; steel withstands more load.
• Finish: annealed, galvanised, plastic-coated. Black and white indicate annealed wire; galvanised is protected against rust; plastic-coated adds a coloured sheath.
• Size number: some wires are given a size number. Always check the diameter in millimetres as well.
• Format: coils and reels. Choose according to how much wire you use and how you use it.
• Type of turnbuckle: standard, pull-type, spring or dynamometric. The dynamometric type lets you read the tension and avoid exceeding the load limit.

Common mistakes

• Using black annealed wire outdoors for long periods. It rusts: outdoors, galvanised or plastic-coated is better.
• Choosing a wire that is too thin for a fence. It gives way under tension or in the wind.
• Tensioning beyond the load limit of the wire. It breaks, and the ends cut: wear gloves.
• Cutting with unsuitable tools. You need wire cutters or pliers, not scissors or other tools.
• Tensioning a wire without checking the fixing points. If the post or anchor gives way, the wire goes slack and can whip back.

Frequently asked questions

What is annealed wire?

It is annealed iron wire, that is, heat-treated to make it soft. It is easily tied by hand or with pliers, which is why it is used for rebar.

Galvanised or plastic-coated?

Galvanised resists rust and is simpler. Plastic-coated protects even more and has the advantage of colour, for fencing and greenery.

How do you tension a wire?

Fix it at the ends and use a wire strainer or a turnbuckle, pulling a little at a time. Do not exceed the load stated for the wire.

What do you cut wire with?

With wire cutters or pliers suited to the thickness. For tying, twist it with pliers or a tying tool.

To see the wire, wire strainers and turnbuckles available, open the metal materials and wire collection: for quantities and sizes, ask the AMES technicians for a quote.