what is a good gauge of wire is good to use as feeders?
30 gauge
I presume by feeder wires, you are referring to the wires that connect from the bus wire to the track. I use DCC so my requirements may differ from yours, but I use 14 gauge wire for my bus line and 18 guage for my feeders. Every peice of flex track is soldered and I attach a feeder wire every three feet or so.
Even if you are running DC, I suspect that 30 gauge wire is too thin for all but the smallest layouts. The wire that Atals and other sell is 22 gauge.
Here’s my 2 cents worth on the subject. Actually, it’s more like a nickle’s worth, but what the heck.
Wire has resistance, the thicker the wire (the smaller the gauge number), the less the resistance. #18 wire (lamp cord) has 2.5X the resistance of #14 wire (house wiring), #22 wire has 2.5X the resistance of #18 wire and #30 wire has 6.4X the resistance of #22 wire. This resistance has more effect as the current consumption increases–N scale motors and can motors can use lighter wires than O scale motors, and short runs can get away with lighter wire than long runs. And don’t forget that you have to take into account the length of both wires which go out to your track.
Feeder wires which go from the track through the layout can be quite light if kept short (2-3 inches). #22 should be okay for N and HO scales, #18 for anything larger. For small to average sized layouts in N or HO, #18 buss wires should be okay, and #14 for larger scales. For room-sized layouts, I’d say use #14 buss wires.
If you will be using DCC or plan to have multiple engines on the same throttle, I’d say you should go to the next larger wire size (#12 instead of #14, #16 or even #14 for #18 and #18 for #22).
#30 wire is, in my opinion, totally unacceptable for track power, as is scrap multiple conductor telephone cable, which would be either #24 or #26 wire. The easiest way to get #12 or #14 wire is to strip them out of house wiring. The conductors are solid. Lamp cord, which is what is used on lamps and appliances, is a good source of #18 stranded wire, and can be bought in bulk at hardware stores. #18 and #22 solid and stranded wire is available at Radio Shack. You can also get wire in different sizes at automotive supply stores, but it would be more expensive there. Dorbell wire and the telephone cables which are meant to be installed inside the walls of the house (not the ones attached to the telephone) are usually #20 solid wire and are quite inexpensive.
In