I started laying track on my layout using code 70 Micro Engineering weathered track, assuming I would use the ME code 708 turnouts, only to find that they are not DCC friendly. I’ve heard that the walthers turnouts might be dcc friendly, but I think that’s just in HO scale. Are there any dcc friendly code 70 turnouts available for N scale at this time? Should I just go ahead and use the ME turnouts?
Are you willing to learn how to wire and gap a “traditional” turnout? Are you willing to add a contact to your switch machine or throw mechanism, and a feeder to the frog? If yes, the ME turnouts will likely work very well for you, and will have live frogs where smaller locos will not stall. And you can take advantage of the power routing capabilities of the turnouts to prevent running turnouts that are thrown against the locomotive.
But if you are not willing/able to understand traditional DC wiring and gapping, you are better off with Atlas or Peco Insulfrog turnouts. The other downside is that occasionally on a traditional turnout where the open point to stock rail gap is not as big as it should be and/or or a wheelset is narrow in gauge, you can get a momentary short from the wheel touching both the stock rail and open point at the same time. Usually some fine tuning of the offending wheel set and/or the turnout can fix this.
Over the past year or two, ME has been upgrading their turnouts to “DCC friendly” where the points are no longer tied together electrically. They have labeled these as “DCC friendly”. I don’t know if the upgrades have been made to the N line yet - your LHS may just have the older ones until they sell out.
Hope this helps.
Fred W
I have read about modifying the turnouts to be dcc friendly, however it seems like a lot of work. I was hoping there would be a code 70 DCC friendly N scale turnout, but the more I look, the more it seems like there is not. My choices would then be to 1) use the turnouts as is, or 2) use different code rail, i.e. code 80 with peco insul-frog turnouts.
Why is this such a problem for DCC as opposed to regular DC?
There is a lot of, IMHO, over-blown hoopla about “DCC-friendly”. Preventing short circuits is more of a concern in DCC than in DC
- because the circuit breakers must be fast-acting to prevent damage to the DCC electronics
- because a short circuit shuts down the entire power district (and all trains in it) instead of just the train in question (DC block control).
- because a short circuit in DCC can involve much higher currents than in DC. In DC, track voltage is often in the range of 3-9 volts; in DCC 12-14 volts is the norm. In DC, most throttles are limited to about 1.5 amps, many DCC systems can put out 4-5 amps until the breaker pops.
That does not mean a short circuit in DC is a good thing, just that the consequences do not impact operations and equipment as much. In the past, the best way to achieve both mechanical reliability and freedom from stalling in a turnout (in the days of brass rail and limited engine pickups stalling was a far bigger problem than electrical shorts!) at a reasonable price was deemed to be using metal frogs with points joined by a metal tiebar. Electrically, this “traditional” turnout had the advantages of shutting off the track that the turnout was set against, and required no internal jumpers or external feeders.
The biggest problem with traditional turnouts is that the point-to-stock rail contact proved to be electrically unreliable, and resulted in stalling beyond the points. The fix is to add a feeder for the frog whose polarity is controlled by an electrical contact that moves when the points are thrown.
The distance between the open point rail and the adjacent stock rail is by NMRA standard wide enough to prevent a properly gauged wheel set from bridging the point and stock rail. There are occasions where this open point rail-to-stock rail gap is not set wide enough, or a wheel set slightly narrow in gauge can create a momentary short circuit by bridging the stock and open point rail.
To
I’ve heard some say that Peco turnouts can be used “as is” with DCC, but I have not verified this myself. I’m not sure if they have a code 70 line or not.