Need professional advice update

[Mr Mechanic]

The fingernail polish is sounding like a better fix. Cutting the track, would the other truck,that has power, re power the cut part of the track when running over it through the board? I am running long diesel engines.

[bapguy]

 Another fix would be to cut a gap in one rail just to the right of the frog. Use a saw or cut off disc. I have Atlas turnouts and all of them, I gaped one rail on the diverging side of the frog and added a  power wire past the gap. No problems at all.  Joe

[jward]

The fingernail polish is sounding like a better fix. Cutting the track, would the other truck,that has power, re power the cut part of the track when running over it through the board? I am running long diesel engines.

if you have cut gaps in both rails, then they are both isolated from the rest of the layout, and thus won't short.

[James in FL]

I wouldn't cut anything just yet.

the obvious solution, to respace the guard rail to nmra specs, would require a lot of work, including removal of the existing guard rail and fabrication of a new one. you'd have to do this for each guard rail.

Why remove the guard rails if not necessary to fix the problem?

The obvious solution, to at least one other of us (but admittedly I'm not an expert), is to shim the guard rails.

Start with .005 shims, it that's not enough increase it. 
Use goo or Aleens tacky glue as a temporary glue, until you find the right amount of shim, then use super glue.

FWIW... the clear nail polish application has merit and has been used for decades very successfully.

Good luck

[Mr Mechanic]

Cutting the rails wont stop the shorting. I did a little experiment, I took 2 straight track and laid them an inch apart.With track power to just 1 section and with the engine straddling the gap, there is power to the other section of track through the engine. No matter where I would cut the track,it would be fed power through the engine as soon as the engine went across the cut. I would need to make the isolated space longer than the wheelbase of the engine to stop the short and then the engine would stop on the isolated section. Nail polish,I think,will be my best bet.

[jward]

your short occurs because the backs of your wheels are rubbing one rail while riding on the rail of opposite polarity. by cutting gaps in both rails, you are in effect lengthening the dead section just enough that the wheel backs won't come into contact with the rail of the opposite polarity. the gaps prevent this. even when they are being bridged by a locomotive truck, the dead rails are only being energized by one polarity. thus there will be no short. try it yourself and see.

when I hand build my switches, I do not use plastic frogs. they are pieced together from rail filed to fit. I cut gaps in the rail as I described to isolate the frog from the rest of the switch. they never short on me. as a matter of fact, with all rail frogs like I use, I have the option of powering the frog through contacts on the hand throw, or switch motor, to eliminate the dead spot completely.

[Mr Mechanic]

I think I understand what to cut now, The rail that the back of the wheel is coming into contact with, not the rail it's on, makes sense now. In the picture,it would be the rail under the screwdriver.

[Mr Mechanic]

Correction, need to cut both rails because when its on the other rail the wheel can come in contact with the opposite polarity. In the picture,the rail that the screwdriver is on and the one below it.

[jbrock27]

I've used both nail polish and black automotive touch up paint, but on the side opposite of where the screwdriver is, where the Frog makes the triangle where the two rails meet.  The automotive paint has held up better.

Mr., "Snap Switch" is a non-numbered turnout, meant to have the curvature of an 18"R curved section of track for the divergent route.

Also, from the NMRA website:

Another area of difference can be seen in the frog of the turnouts. This is where the rails cross each other. Some turnouts have metal frogs and some bring the rails up to each other, then insulate them with plastic. If a metal frog is insulated but not powered, you may have some locomotives that will stall on the switch. This is more likely in N than in HO. Even in HO, some locos don't pick up power on all their wheels, giving trouble on some No. 6 switches. Atlas has a product called a "Snap Relay" that will power their Custom Line Mark II and III turnouts if you experience this problem. Some turnouts come with a long switch machine mounted on one side, while others have removable machines, and there are also 'under the table' electrical switch machines. There are manual 'ground throw' switch machines, too. Caboose Industries makes one that looks much like the real ones, and it works well. Atlas, Bachmann, AHM, Life-Like, Model Power, Roco and Tyco turnouts are all electrically interchangeable and all use the same size of rail.

Now, after talking about all of this, there is another kind of turnout which matches the above types physically, but is electrically different. Those listed above have the siding electrically live with the same power as the mainline unless an electrical toggle switch is installed. The other kind of turnout is called a selective turnout. It selects the way the power is routed by which way it is thrown. When it is thrown for the siding, the siding is powered and the straight route goes dead. When it is set for the main, the siding is dead. This creates a different wiring situation, and you must be certain that the rails leading out of the turnout are properly insulated to prevent shorts.

[Mr Mechanic]

Cutting the rails,I am not sure how far up the rail the feed from underneath is,it might be all the way to the end of the rail, and I am worried that the short isolated rail might not have enough support and might loosen up. jbrock27 that is where I thought it was shorting out to begin with, but as you can see from the picture, right in front of the screwdriver, the marks where the short was happening.Going to use some paint and that should fix my problem. Thanks again for all of the advice.

[jward]

Correction, need to cut both rails because when its on the other rail the wheel can come in contact with the opposite polarity. In the picture,the rail that the screwdriver is on and the one below it.

exactly. the whole point is to keep the wheels from contacting two energized rails of opposite polarities. another mod that can be made and probably should be made is to solder a jumper wire between the stock rails and the rails on the far side of the frog. atlas switches rely on the pivot plate at the hinge end of the points to conduct electricity. in your case that is probably a brass rivet. those are a known source of trouble when they oxidize over time and lose contact. you can't solder the hinge point itself but you can solder anywhere else on the closure rails, both before and after the frog.

[WoundedBear]

And I have to agree with James in FL. I would start by shimming the guard rail as well. The method he described is spot on correct in my books, and far easier than cutting into the rail.

Sid

[James in FL]

Model railroading is not rocket science.

The reason you are having "shorting" problems is simple deduction.

Your wheels are not in gauge,
Or,
Your turnout is not in gauge,
Or,
Both.

The shorting is not the problem, but rather the result of at least one of those three.

Root cause.
Cause and effect.
Troubleshooting 101.


Nothing need be cut.

[jbrock27]

To James' points, the NMRA gauge I previously mentioned, would also help with this kind (wheel gauge) of trouble shooting. Among the model RR tools to have, it is in the top 5.

[Mr Mechanic]

NMRA gauge is on my list of things to buy and the coupler height gauge. I have replaced all the wheels with Bachmann 33" metal wheels #42904. I would say the turnouts are probably out of gauge as old as they are. The paint is drying now,I think that will solve my problem.