Bare / Bus Bar Wire
Bare copper bus bar wire for grounding, common bus connections, LED array wiring, and point-to-point electronics assembly. Bare wire makes wiring up multi-LED projects dramatically faster — no stripping insulation at every connection point, no fumbling with wire strippers in tight spaces, no melted insulation fouling your solder joints. Just lay down the bare conductor, solder each LED lead or component leg directly to it wherever you need a connection, and move on. It is the fastest and cleanest way to build LED matrices, common ground buses, common positive rails, and multi-component parallel circuits on perfboard and custom wiring harnesses.
Why use bare wire for LED projects? When you are wiring a row of LEDs — whether it is 12 building windows on a model railroad layout, a row of instrument cluster backlights in a GM Silverado dashboard, a panel of indicator LEDs on an escape room prop, a string of decorative LEDs in a holiday display, or a grid of LEDs in a custom matrix — bare wire eliminates the most tedious and time-consuming step in the entire build: stripping insulation at every single solder joint. With insulated wire, you cut to length, strip both ends, strip intermediate points where you need to branch off, and carefully avoid melting the insulation with your iron at each joint. With bare wire, you cut a single length, route it where you need it, and solder directly at every connection point. The result is faster assembly, cleaner joints, a lower profile, and fewer failed solder connections caused by melted insulation contaminating the joint.
Common ground bus wiring: The most popular use of bare wire in LED circuits is as a common ground bus. Run a single length of bare wire along your row of LEDs, then solder each LED's cathode (negative lead) directly to the bus. Each LED's anode (positive lead) connects through its own current-limiting resistor to the positive supply rail (which can also be bare wire running parallel). This creates a clean, compact parallel LED array with individual resistors per LED — the recommended wiring method described in our parallel wiring guide. The bare wire bus is especially effective on perfboard, where you solder it to the underside of the board, running in a straight line along a row of holes.
Model railroad applications: Model railroaders are among the heaviest users of bare bus bar wire. DCC track bus wiring uses heavier gauge bare or tinned copper wire (14–16 AWG) running under the layout benchwork, with feeder wires soldered directly to the bus at each track section. Building lighting buses use thinner bare wire (22–24 AWG) running through structure interiors, with individual LED cathodes soldered at each window or room location. Yard lighting and platform lighting arrays use the same technique — one bare wire bus for ground, one for positive, with LEDs and resistors bridging between them at each light position. The NMRA (National Model Railroad Association) wiring standards reference bus bar wire specifically for power distribution in DCC layouts.
Perfboard and prototyping: Bare wire on the back of a perfboard creates trace-like connections without the cost and lead time of etching a custom PCB. Run bare wire between component pads to create point-to-point wiring that is clean, inspectable, and easy to modify. This technique — sometimes called "dead bug" or "Manhattan style" wiring — produces professional-looking prototypes when done carefully. For breadboard prototyping, bare wire is used to make custom-length jumper wires that sit flat against the breadboard surface, keeping the layout organized. Cut bare wire to length, bend the ends to 90 degrees, and insert into the breadboard holes — much cleaner than using pre-cut jumper wires of fixed lengths.
Wire gauge selection: Gauge determines current capacity and rigidity. 24 AWG is the go-to for small LED arrays (under 20 LEDs at 20mA each) and perfboard wiring — it is stiff enough to hold shape but thin enough to route easily. 22 AWG handles larger arrays and longer runs with less voltage drop. 20 AWG is suited for power distribution in medium-current applications. 18 AWG and heavier is used for DCC track bus wiring and power distribution trunks where total current exceeds 2A. For single-LED connections and model railroad structure wiring where the wire needs to be nearly invisible, insulated 30 AWG Kynar wire is a better choice — but for multi-connection buses where you are soldering to the same wire in multiple places, bare wire is the superior solution.
Bare copper vs. tinned copper: Bare copper is raw copper with no coating — it conducts well and solders easily when fresh, but oxidizes over time (turns dark brown or green), which makes soldering harder on wire that has been stored for months or years. Tinned copper wire has a thin layer of tin (solder alloy) coating the surface that prevents oxidation and makes soldering quick and reliable even after extended storage. For projects where clean solder joints are critical or where the wire will be stored before use, tinned copper is the better choice. Both conduct electricity identically.
For insulated hookup wire, heat shrink tubing, and connectors, browse our complete Wire / Switches / Connectors section. Need resistors for your LED array? Use our LED Resistor Calculator to find the right value for each LED. Control your circuit with one of our switches, and choose LEDs from our component LED catalog of 700+ varieties.