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A helix is just a straight track that's not straight - simply solder all the rail joiners together and you'll need only one pair of feeders if you're running DCC. If you're using DC, solder it to the tracks on either end and your're in business.
Wayne
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Oh, I was under the impression that if I took a helix and straightened it out, I'd have a good 24 feet or track. I thought I needed to drop down feeder wires to help keep the current from the bus line from dissapating?
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If the rails are soldered together, each becomes a single conductor without interruptions, just like your bus wire. I keep seeing this need for constant feeders for DCC, but it seems like a lot of work and a waste of wire. My DC-powered layout has over 200' of main line, all powered by two feeder wires. If you're not soldering rails together, then every length of rail requires a feeder - rail joiners are not reliable conductors of power. While a helix is unlikely to be ballasted or have its rails painted, these operations increase the chance that the unsoldered joiners will lose contact: without soldered joiners or, alternatively, feeders for every length of rail, finding such a fault becomes time consuming.
Wayne
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Wow, thanks doctorwayne. I never thought about that - having rails soldered together makes them act as a single conductor without interuptions. I've seen pictures of helixes with just a ton of wire hanging off the sides of them, and I gotta admit, it's a real eye sore. Just like you said as well, having feeders for every length of rail and having a fault would take a long time trying to figure out where the problem is coming from. Thanks for the advice, it'll be going a long way
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I've learned the hard way. Having a helix that has an inside radius of 26 inches, and an outside radius of 28 inches, will not allow 2 90 foot auto racks to clear. Even by making the inside loop 24 inches, with the space that I have available, still won't work. Looks like there will be at least 1 Timetable Special Instruction dimensional clearance rule in the rule book.
hock:
