Introduction
If you’re buying wire in order for any purpose, you’ll eventually need to choose what kind of wire you want to buy. There are a few factors to consider when you want to buy wire that will suit your needs:
1) Wire gauge/AWG
This is the most important factor in wire selection. The larger the AWG, the heavier of a wire it is. This has two major effects: a) it decreases resistance – meaning that coils will heat up faster, and b) it increases how much current can flow through the wire. Bigger wires (60+gauges) are generally cheaper than smaller (16-27 gauges). The amount of current that passes through the wire by its diameter is called “kΩ/cm”. We do not recommend using any wire with a kΩ/cm less than 500 since it can fail without warning.
2) Resistance
The next most important factor is resistance, measured in mΩ. As you can imagine, thicker wires have higher resistance than thinner ones. This is usually a factor of two or three for 16-27 AWG wire, and almost all 30+ gauge wire has more resistance than 1/0AWG. Resistance is not as important to consider as diameter of the wires, but it definitely plays a role.
3) Current conducting capability
Since this post is about how to buy wire, we won’t go into more detail on the importance of current conducting capability here. This generally means how much current a wire can carry safely before melting.
4) Length/quantity
For coils, the shorter the wire that you use, the lower the resistance. However, longer wires can be easier to hide and are sometimes cheaper. Some people might also prefer to use thicker wire because it increases the space between the coils (for example, 808 sized wire can fit more than 10 smaller wires in any given space). Length is still a factor but not nearly as important as diameter, resistance and current conducting capability.
5) Tolerance
Most manufacturers put a certain amount of tolerance on their wires, and it is important to understand what the tolerance means before buying. This depends on the type of wire, but most 16-27 gauge wires (including oxygen free copper) have a +/- 5% tolerance. This means that if you ordered 100 feet and received 97 feet of wire, you would receive 9 feet of excess wire (e.g., 97 – 95 = 2). 6% is standard in the wire industry, and it usually denotes a +/- 3% tolerance.
6) Price
The price is one of the most important factors to consider when buying a wire. The price of wire is not high, but some types of metal are too expensive for everyday use. It’s good to find a price that is just right for you.
Conclusion
When buy wire, there are a few important things to consider. The most important thing is to know how much resistance your coils will have. After that is AWG and current-conducting capability. From there, you can decide what kind of wire is best for you. For a more in-depth look at different types of wire and you will establish what can best suit your needs.