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I concur with 34C.

There are two solutions:

1) Make sure that your track-bed is flat/level and ensure that your turnouts are firmly attached to it. Some people do this by putting pins through the middle of the turnout. Personally, I prefer to glue it down with weights located on top until the glue dries. My mirror tip will help you look along the tops of your rails: Using a Mirror to Align Track - Model Railways On-Line

2) Having dealt with (1), run a file across the common crossing (the V). You may find that it is slightly raised, in which case, you can file it down level with all the other rails. As 34C indicated, Peco are usually pretty good with this now, although it used to be an issue in the past.

HTH
 

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The momentary short is usually not enough to shut down the command station, but is enough to deprive the loco of power.

It should be possible to rewire the points as if they were live frog, but a bit of a big job after the track has been laid due to the need to fit insulated joiners.
Even in my very early DC days, I recognised that this was a problem with dead-frog turnouts, so I treated them like live frogs and fitted IRJ's to the back end of the crossing and power fed from the toe.
Once I discovered live frog turnouts, I have never used anything else since.

Remember that a short in dead or live frog will only occur where two opposing polarities are in close proximity and something like a wide wheel tread or out of gauge wheels can bridge between them.
Best practice is always a good idea to wire so that opposing polarities are never close together or of there is a risk that they could be, that one rail is isolated ie not connected at all.

Wiring live frog turnouts here: Live Frog Wiring - Model Railways On-Line
 

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If you are still getting stuttering and the command station stays stable (ie no cut-out due to short), it would suggest to me that there is a loss of power.
Although you've checked that the pickups are contacting the backs of the wheels, it doesn't necessarily mean that they are making good electrical contact.
If you haven't done so already, may I suggest that you position you loco upside down and connect two wires from the rails to the wheels on one wheel set at a time while power is running. The purpose of this is to check the continuity of each individual wheelset and its pickups. Wobble the wheels a little to see of the motor stops - I highly suspect that you may have some axles which are not fully making contact, in which case, the pickups may need tightening up a bit more.

It could also be an issue of lifting. Since centre driving wheels on a crossing seem to be a common factor, it suggests that there might not be any vertical movement possible in the other wheelsets, although this would be unusual. Having said that, I have filed groves in chassis base plates before to enable a little axle vertical movement for exactly these situations. Be careful with this approach as it can be a case of solving the symptoms (stuttering, which some people mis-identify and end up using stay-alive) rather than the root problem - track which actually is raised - try my mirror technique above to see if the rails are raised.

If that doesn't cure the issue, then yes, electrofrog is the way to go.

HTH
 

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Hi Julian, thanks for your suggestion. Having played about with some kitchen foil to confirm the frog is the issue (rather than the closure rails or switch rails), I am thinking along the same lines as yourself.
I believe what is happening is that at very slow speed the loco wheel is 'dropping' off the V of the frog causing one or more of the other wheels on the opposite stock rail to rise slightly and lose electrical contact, when the loco tips slightly towards the frog. Using a test wire between stock rail and those wheels re-establishes contact and the loco starts moving again
This reminds me or something I forgot to mention earlier.

Uneven passage across a crossing V isn't necessarily the V itself protruding upwards. It could also be the wheels dropping into the V which is what you appear to have identified.

There are a few ways of dealing with this:

1) Dropping into a crossing is often caused by the back-to-back measurement of wheelsets being less that what they should be. They should be 14.5mm for 00 scale. Try correcting the gauge (not always easy on locos), but at least you should check it.

2) Similarly, the gaps between rails and the depth of the crossing also have an impact. As others have already indicated, SetTrack is a 1960's/70's phenomenon, designed when steam-roller wheels were all the rage and deep flanges were fitted to match. SetTrack and Peco 'universal' was designed to be compatible with this and still is, consequently, the tolerances on check rails and crossings are way more than what they need to be for modern stock.
I suspect you may be running relatively recent stock on 1960's standards track and this is why you are having problems.

3) Insert a shim of plastic in the bottom of the crossing. The purpose is to allow flanges to run along it instead of dropping further into the V. Peco actually do this on their 7mm scale turnouts. It's not my preferred option as gauging wheels normally fixes the issue, but if it works for you, it may be a way to go.

I recall about 20 years ago, taking my rolling to stock to run on someone else's layout. My layout is Peco code 75 and wheels are gauged to match. Perfect running all the time and still is. The other person's layout was SetTrack. Needless to say, my stock spent more time off the rails than on them. It was a waste of time trying to run decent models on crap track.

Set Track really should be confined to the bin. It isn't suitable for modern models and this is why we have things such as the code 75 and bullhead track ranges which are way better.
 

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Have you not tried a "stay alive". If you don't want to re-lay track (& I don't blame you) that's what you need to look at next. There is just an inherent problem with short wheelbase locos and insulfrog points. Also, if you are using DCC you need to install some snubbers (RC filters) to absorb the momentary shorts that someone mentioned earlier.
Please don't use snubbers.
The problem here is one of loss of continuity, not shorting.
If one has shorting happening, then one should be fixing the shorting, not masking it.
This is why things such as 'hex-juicers' (devices purposely designed to depart the less-informed from their money) shouldn't be used on DCC layouts because they interrupt digital signals. What tends to happen next is that people are encouraged to fit snubbers to fix the signal interruption problem when they should be fixing the shorting problem.
Please fix problems, don't fix symptoms and please don't encourage solutions that mask problems.
 
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