Turnout woes..

[jacon12]

I have a particular turnout, a Peco large radiius... that's giving me problems and I kinda new at working with them so I come to you guys.  The problem is it has suddenly started to short when just about any of my locos crosses it.  Most of the traffic on my layout crosses this turnout from right to left when looking at the photos below.

At first I thought the problem was at the points, that the loco's wheels were picking them..

but after watching as close as I can it looks more like the problem is in the area noted by the red arrow below (frog?)..

Short of pulling the turnout off the layout, what can I do to correct this problem.

Thanks!

JaRRell

[ARTHILL]

I had one engine where the screw holding the tender coupler was long and touched the frog, shorting it out. I had another where the flanges rubbed. Neither of these sound right for you in that all your engines cause the problem. Some time with a multimeter may show a short that has developed within the turnout itself. I am assuming this turnout is not part of a reversing loop, or a DC block where wires could have shorted or been misplaced.

 

Replacing  the turnout could be the short way to find the short. Good luck.

[GearDrivenSteam]

That Peco turnout is probably a live frog. Unless you have insulating rail joiners, my guess on what's happening is that the loco wheels are bridging the gap between the two rails I have pictured below. If that happens, then it's short city. Peco recomends insulating the frog rails anyway. Have a look and see what you think.

Insulating rail joiners might be all you need.

[selector]

JaRRel, it is an easy fix.  Get some clear lacquer, whether nail polish or varathane, and dab some on the rails where the frog points come together, but at the "fat" end, where the plastic and rails meet.  In the photo directly above my post, in the red circle, add, and let dry, two layers of this "insulation" to the point where the way-too-wide HO scale wheels can't actually make contact with both rails at the same time...which is the problem.  I have had perfect succes with the paint job, and you won't be able to tell it is there...until is wears off and you will know what to do.

I can tell yer havin' fun.

[modelmaker51]

The problem is that both rails after the frog are energized and the wheels are touching both rails as they pass over the frog.

The solution I have seen here is to paint some clear nail polish on the rails from the plastic point of the frog on, (paint about 3/8" to 1/2"). This will have to be repeated from time to time as the coating wears away.

My solution is more permanent, take a dremel with a cutoff disc and grind each rail head to thin it from the inside by about half its thickness for a distance of about 3/8". Fill the groove created with epoxy and even it with the railhead when hardened. Be careful, you're only grinding enough away so that the wheel treads don't touch both rails as they pass through the frog. You don't need to go any deeper than about 1/16th of an inch.

[jfugate]

Yep, gotta love those Peco turnouts.

Peco turnouts come in two flavors -- insulfrog and electrofrog. Electrofrog is a live frog Peco, while insulfrog is dead frog with all the proper gaps in place around the frog.

Unfortunately, Peco insulfrog turnouts have a flaw in them ... the two rails on the inside just past the frog come very close together and are insulated by the thinest bit of plastic near the point of the frog. As shown in the photo below, a standard width HO wheelset can easily bridge these two rails and cause a short at the frog.



(click photo to enlarge)

To solve this problem I cut gaps just past the frog at the location shown. Cutting these gaps is a very tricky operation and needs to be done carefully. I always first put a couple drops of superglue in between the two inside rails, then I cut the gaps very slowly using several passes from a motor tool with a heavy-duty cutoff disk in it.

Once I cut the gaps I fill them with styrene that I superglue into the gap and trim with a fresh sharp single-edged razor blade. This restores some of the structural strength to these two short pieces of rail -- otherwise they tend to pop off the plastic ties and then you have just about ruined the turnout because this is very hard to repair.

But this neatly solves the short problem at the frog, which is what I suspect is causing your issue.

[jacon12]

Yes, I forgot to mention that it's an Insulfrog turnout.  I appreciate everyones suggestions on a rememdy and Joe, the picture (diagram) is worth a thousand words.  I've been wondering just where the wheels touch and now I know.   I'll give the nail polish trick a try to see if that helps, I have a feeling it will.

Let's see..... where does she keep that stuff....

Thanks guys!

JaRRell

P.S.  OH!!!  How often does this happen?  Rare... now and then.. almost never?

[GearDrivenSteam]

Joe, wouldn't putting insulating joiners on the frog rails do the same thing?

[jfugate]

Joe, wouldn't putting insulating joiners on the frog rails do the same thing?

Electrically, yes, but in practical terms ... with an insulfrog turnout that would create a very long dead section and that's not good. You want the dead section to be as short as possible, hence cutting the gaps as shown in my post.

Make sense?

[jacon12]

I'll probably end up doing this as Joe says, but for the meantime I'll try the clear nail polish and see if that works.  Just so I understand, is the area of track in red the place I do the painting?  (Please disregard the larger red arrow).

Thanks,

JaRRell

[jfugate]

I'll probably end up doing this as Joe says, but for the meantime I'll try the clear nail polish and see if that works.  Just so I understand, is the area of track in red the place I do the painting?  (Please disregard the larger red arrow).

Yes, but you only need to go out to between the two ties in the red area shown -- just to the right of your clear polish arrowhead (about half as long as what you show). You don't want the insulated section to be any longer than necessary or then you will get the reverse problem ... things will stall on the frog instead of short.

[GearDrivenSteam]

Sure, but I was talking about before, when everyone assumed it was an electrofrog. Insulated joiners would work there, right?

 

Thanks, Joe.

[jacon12]

I'll probably end up doing this as Joe says, but for the meantime I'll try the clear nail polish and see if that works.  Just so I understand, is the area of track in red the place I do the painting?  (Please disregard the larger red arrow).

Yes, but you only need to go out to between the two ties in the red area shown -- just to the right of your clear polish arrowhead (about half as long as what you show). You don't want the insulated section to be any longer than necessary or then you will get the reverse problem ... things will stall on the frog instead of short.

Ok, I got it.... half as far.

Thanks Joe,

JaRRell

[robert sylvester]

 Jacon 12: Make sure you read Joe Fugates response, there are some others that may have said the same thing. When I was at the Atlanta NMRA convention 11 years ago, boy it has gone by fast, I was at a layout with all Shinoharah turn outs and I noticed how smooth the engines went throught the turn outs. The builder advised me about making a cut in the two tracks that come into the frog, and by doing so would keep the metal wheels of engines and rolling stock from shorting out the switch.
I have actually done that to all of my switches and things run so much better, not shorting out over the frog on a turn out any more.
Yard Master
WTRR

[jacon12]

I tried the nail polish and it seems to have worked like a charm.  Thanks Selector and other who suggested it.  I know it's a temporary fix but at least I now know that was definitely the problem.  I learn something new everyday around here.

Joe, I do have a question on your suggested remedy.  I understand where to make the cut and to use the superglue on the inside as shown below..

but, I don't quite understand the 'jumpers' you have in your picture.  Do I need them if the track on the other side of the turnout is 'live'.. i.e. part of the mainline?  I just need them for the passenger siding which this turnout services, right?

Thanks!

JaRRell

[jfugate]

ja:

Actually, you need to cut closer to the frog. Like this:


(click photo to enlarge)

Remember, you want the dead frog section to be as short as possible to minimize issues with stalling.

Because this is so close to the frog, you will want to make the cut slowly with a motor tool cutoff disk. Take your time and do it in several passes (6-10 passes is about right). You don't want the rail fragments on the frog side to come lose or you will have a bear of a time fixing things. If they do come lose, get some styrene that's larger than the hole left by the missing rail (some black scrap styrene is ideal), superglue it into place, and then once its had time to set up really good (30 min or so is good -- sooner if you use accelerator on the superglue) then trim it to shape with a fresh sharp single-edged razor blade or a fresh sharp xacto blade.

Also fill the gaps with styrene and superglue them, and trim to shape with a sharp blade.

I've done this to all my pecos and they work great -- short problems are history and I don't have to ever go back and apply anything to the frog area.

Peco turnouts have jumpers embedded in the ties that electrically connect the closure rails to the inside rails past the frog, giving them power. Once you cut these gaps you often sever these jumpers, so you will need to power the two rails past the gaps with feeders or they will probably be dead. That's what the jumpers / feeders note in the original drawing is all about.

[selector]

If you do the cuts, it will be quite a gap if you use a cut-off Dremel-type disk, at least if I'm doing the job.   If you could spring for a jeweller's file, you would hardly see the gaps, and they would work like a darn.  The problem with making the gaps, though, is that it now isolates both rail sections leading to the frog point.  Smaller steamers with few pickups will possibly stall when their separated pickups don't span to the live parts.  So, you must solder tiny jumpers from the opposite side outer rails to those small isolated ones to keep them powered, or hook up directly to the closest correct feeders.

Means drilling holes and doing some tiny soldering, but...so what?

[modelmaker51]

My solution is more permanent, take a dremel with a cutoff disc and grind each rail head to thin it from the inside by about half its thickness for a distance of about 3/8". Fill the groove created with epoxy and even it with the railhead when hardened. Be careful, you're only grinding enough away so that the wheel treads don't touch both rails as they pass through the frog. You don't need to go any deeper than about 1/16th of an inch.

My method is much simpler. You don't have any gaps to fill or jumpers to solder. No flying pieces of rail either. You basically just grind out a little 3/8th in. long divot (about 1/16" deep) between the rails. Just check to see when the wheel tread no longer touches the other rail.

Selctor: What are you using for a cut-off disc? Is it one those big fibreglass re-enforced discs? They are indeed way to big. I'm talking about the quarter-sized 1.5mm thick cut-off discs and I think Joe is as well, they only make a about a 2mm gap.

[jfugate]

Modelmaker:

You're right, your solution is much simpler. Where were you when I was altering all those Peco turnouts?

This old dog just learned a new trick!

[selector]

Modelmaker, I used a very thin diamond-studded wheel, and it still created a 1.5mm gap, despite my best efforts.  I think that is too thick by about .7 mm; it looks terrible.  The jeweller's file is amazing, although very delicate.  It is what Tim Warris of Fast Tracks recommends for gapping his frogs. Just like his jigs, and spline roadbed, once you have done them, there is no going back. 

[jacon12]

My solution is more permanent, take a dremel with a cutoff disc and grind each rail head to thin it from the inside by about half its thickness for a distance of about 3/8". Fill the groove created with epoxy and even it with the railhead when hardened. Be careful, you're only grinding enough away so that the wheel treads don't touch both rails as they pass through the frog. You don't need to go any deeper than about 1/16th of an inch.

My method is much simpler. You don't have any gaps to fill or jumpers to solder. No flying pieces of rail either. You basically just grind out a little 3/8th in. long divot (about 1/16" deep) between the rails. Just check to see when the wheel tread no longer touches the other rail.

Selctor: What are you using for a cut-off disc? Is it one those big fibreglass re-enforced discs? They are indeed way to big. I'm talking about the quarter-sized 1.5mm thick cut-off discs and I think Joe is as well, they only make a about a 2mm gap.

Jay, thanks for the suggestions.  If I understand you, you're saying to grind out an area that is in red in rail #1 in the below picture?  Do you do anything to rails 2,3, and 4? 

Selector and Joe, I really appeciate your suggestions!

JaRRell

[selector]

That's it, JaRRel.   You can appeciate that this will take some thinking, a steady hand, and some decent equipment, but you have it exactly right.  Do a narrow gouge first and verify for about four trails.  If you get no shorts, that is likely to be the 90% solution.  If you still get the very odd one, you can always widen the gouge perimeter by another 10 thousandths..ish.  How you'd get that fine a grind is beyond me.

-Crandell

[jfugate]

I think you want to split the difference and grind both rails equally, ja. If you grind it as you show, you'll fix the problem for trains going through the 2 <---> 4 route, but trains going the other route will still short. Just imagine the wheels going down each route and ask yourself if there's metal the wheels could possibly contact -- and you need to grind that metal back on *both* routes, as shown in red below:


(click image to enlarge)

You want to widen the gap between the two metal rails 1 and 2 where they come together at their closest point, and you only need to grind down part way, then fill the gap with some styrene you superglue in place. Trim the styrene with a sharp single-edged razor blade or xacto blade once the superglue sets up.

Darn clever. Wished I had thought of it -- it would have saved me a lot of work. Modelmaker's approach is a far easier solution to the "metal rails too close at the frog" problem on Peco turnouts.

[claycts]

Joe, are you cutting with a Dremel or a Razor Saw?

I have no peco but your diagram helped on a Walthers 3 way.

Another new trick for this old dog!!

[GearDrivenSteam]

Well what about with the electro frog? Would the insulated joiners on the frog rails eliminate the need for any cutting? Thanks.

[jfugate]

Joe, are you cutting with a Dremel or a Razor Saw?

I have no peco but your diagram helped on a Walthers 3 way.

Another new trick for this old dog!!

clay:

When I cut across the rails just past the frog as I originally showed, I'm using a motor tool with a heavy duty (double-thickness) disk. It makes a wide gap (almost 1/16" -- or just over 1mm) but I glue black or grey styrene into the gap with superglue, then trim it to shape with a fresh sharp single-edged razor blade.

The gap all but disappears when you do that. Don't use white styrene or the gap sticks out like a sore thumb.

[jfugate]

Well what about with the electro frog? Would the insulated joiners on the frog rails eliminate the need for any cutting? Thanks.

Gear:

An electrofrog turnout is a live frog turnout (not dead frog like an insulfrog turnout) and its electrical characteristics are completely different. As long as you use insulated rail joiners at the next rail joint on rails 1 & 2, you will be fine.

With an electrofrog turnout, the closure rails, frog, and two inside rails past the frog are all a single polarity based on the position of the points. An electrofrog turnout has contacts under the points that throw the polarity of the entire "frog assembly" the proper way to match the route the turnout is aligned for.

The big downside of an electrofrog turnout (or any live frog turnout) is you will get a short if you approach from the frog end when the points are thrown the wrong way.

With an insulfrog turnout (once it's properly insulated as we've shown), you can run through one from the frog end with the points thrown the wrong way and you just go on the ground like on the prototype. Notice, no shorts!

On a DCC layout, I recommend dead frog turnouts unless you have lots of older steam locos with less-than-wonderful power pickup or you have really short wheelbase locos that don't like deadspots in the track. An insulfrog turnout (or any dead frog turnout) has the track where the rails cross as a dead section with no power. Most all-wheel pickup modern locos roll right over a dead frog turnout without any problem.

Make sense?

[modelmaker51]

Thanks for pitching in guys, Selector and Joe both have it right.  However I would suggest using some JB Kwick (by JB Weld - Ace hardware carries both) or some plumber's Epoxy putty to fill in the "gouge/divot" and then the razor blade to trim and shape. It's less messy, and you don't risk getting super glue in places you don't want it and a side benefit is that the epoxy is gray and doesn't need touching up to hide it. (I also use the plumbers epoxy putty to fill isolation gaps, it gets hard as a rock and again it's gray so no touch up needed).

You could "practice " on an old brass Atlas switch to get the "feel" of it. Only grind for 2-3 seconds at a time on low to medium speed so the rails don't heat up too much and deform the plastic point of the frog. An Optivisor helps a lot to see what you're doing. Actually, the optivisor has been one of the best tool investments ever, it did so much to improve my accuracy and neatness.

[selector]

I think you want to split the difference and grind both rails equally, ja.

Oops, I missed that.  Yes, I should have realized that JaRRel might have thought that only the one rail needed the adjustment.  Since the wheels are bridging both anyway, then you want the high ridge that the rails ride on, regardless of their path through the turnouts, to be separated by the gouge you are creating. so, for symmetry, and to create the wide gap you need, grind both rails a bit.

Good catch, Joe.

[jacon12]

I certainly appreciate the advice from Jay, Joe and Selector in this thread, and I hope that there will be a lot of other people reading this,  I know there must be more than 'just a few' people to have had this problem.  Jay, thanks for the additional information on the plumbers putty also.

NOW!  All I gotta do is get up the nerve to do a little grindin'.  Oh,  I will practice on an old Atlas turnout, it's the only thing I have.  I have a Dremmel so I gotta figure out what attachment I have that'll get down between those rails and NOT grind in places I don't want to grind.  1/16th inch deep... whew!.. are my nerves that steady.. 

JaRRell