turnout on a curve
- Thread starter unkaboose
- Start date
Iron Horseman
Well-Known Member
Sorry, I didn't mean to imply that the Atlas were still available. I just wanted to point out to the OP what a curved turnouts was all about, and that is the only one I currently have a photo of.
I don't know when they stopped production of the unit. It is too bad, because they are a great piece and fit in with the sectional track exactly.
Cjcrescent
Master Mechanic
At one time back during the 1970's they were available separately and Atlas also offered a #4 double slip as well. IIRC they actually were track from Roco. This of course was when Roco was building the diesels for Atlas, and like the diesels the track pieces were offered under the Atlas name, but weren't built by Atlas.
trailrider
Well-Known Member
OK, people, listen up! (Sorry! Been watching too many military movies lately.) "Power routing" means the way the switch points are thrown determine which branch of track beyond a turnout is powered or not. It has nothing to do with whether the frog is electric or insulated from the adjacent rails. The closure rails (the ones that come together at the frog) MUST be electriaclly isolated from the adjacent stock rails. power to the stock (outside rails) MUST come from "upstream" of the turnout, i.e., before you get to the turnout when the train is travelling toward it from the point rail end. Let us assume that the point rails make good electrical contact with the stock rail when thrown in whatever direction the train is to go. (If they don't, or to insure better feed, you can use contacts on a switch machine.) Power will be directed to whichever route the point rail contacts the stock rail. Say you have a right-hand turnout. When the points are thrown so the train travels straight, the righthand point (as you look from the points to the frog end) will be in contact with the right hand stock rail. The divergent route will be dead because there is no connection between the curving closure rail and the lefthand stock rail. (That's why you have to cut the connecting wire between points and the adjacent stock rail.) When the turnout is thrown for the divergent route (off to the right), the left-hand point and closure rails are in contact with the left (straight) stock rail. The divergent route will be powered and the straight (tangent) route will be dead. BUT... If your turnout is placed in an oval, with the divergent route going somewhere else, you MUST place insulated rail joiners somewhere beyond the frog end of the turnout...and in both main rails in the oval, so you won't have a short circuit when the turnout is thrown for the divergent (in this case, straight) route. Feed the turnout from the point end. The divergent route doesn't need to be insulated if it is just going to a stub siding.
If you do use turnouts with an insulated frog, you probably don't need the insulated rail joiners, but the frog will be dead, which may cause short-wheelbased locomotives to stall. Atlas Snap Track turnouts have plastic frogs which cannot be powered. Atlas Mark IV turnouts (at least the newer ones) have an insulated metal frog, which can be powered from a Snap-Relay, wired in parallel with the Atlas switch machine. The only "bad" thing about the Mark IV's is they don't fit as readily into an 18" radius sectional track curve. Just don't try to solder the lead wire to the frog! The Snap Relay's come with a metal bar and screw that can be used to form a lead to the frog. Attempting to solder the wire directly to the metal frog WILL result in the plastic frog base melting, requiring either replacing the turnout, or, if you get lucky, smoothing out the base and re-attaching the frog, after carefully aligning it, using CA cement. (Don't ask me how I know this!
) You can use Snap-Relays with any other brand of twin-coil switch machine that doesn't have its own contacts. I also use Peco turnouts, both curved and regular, generally with live frogs, but I don't particularly care for their switch machines. I will substitute some older twin-coil machines with more positive throw force.
If you do use turnouts with an insulated frog, you probably don't need the insulated rail joiners, but the frog will be dead, which may cause short-wheelbased locomotives to stall. Atlas Snap Track turnouts have plastic frogs which cannot be powered. Atlas Mark IV turnouts (at least the newer ones) have an insulated metal frog, which can be powered from a Snap-Relay, wired in parallel with the Atlas switch machine. The only "bad" thing about the Mark IV's is they don't fit as readily into an 18" radius sectional track curve. Just don't try to solder the lead wire to the frog! The Snap Relay's come with a metal bar and screw that can be used to form a lead to the frog. Attempting to solder the wire directly to the metal frog WILL result in the plastic frog base melting, requiring either replacing the turnout, or, if you get lucky, smoothing out the base and re-attaching the frog, after carefully aligning it, using CA cement. (Don't ask me how I know this!
) You can use Snap-Relays with any other brand of twin-coil switch machine that doesn't have its own contacts. I also use Peco turnouts, both curved and regular, generally with live frogs, but I don't particularly care for their switch machines. I will substitute some older twin-coil machines with more positive throw force.