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Turnout Frog Sparking

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Turnout Frog Sparking
Posted by NittanyLion on Saturday, August 16, 2014 3:40 PM

So I'm splicing in a turnout after coming across a store with a supply of Atlas turnouts.  While testing to make sure everything was fitting, before painting and such, I ran a locomotive (Athearn BB of indeterminate age (10 years?)) over it and the frog threw sparks when the locomotive ran over it.  Not the little blue ones that you liked when you were a kid.  Big scary orange ones.  It only does it on the divergent route and both directions.  I'm running straight DC too.  They're quite big and I swear it pitted the frog and the wheels on that side of the truck.  I ran it back and forth a bunch trying to see if I could figure out what's going on.  

I tried a second BB (a much older one that I've had for 20 years now) and it did it too.  There's no hesitation or anything.  They just plow right through, looking like they've crushed a guy with a cutting torch.  I also attempted it with a DC BLI F unit that I have and that produced a different result.  No discharges, but the loco would stop dead at the frog.  Either truck too.  Like first truck would stop, I'd nudge it, it would move, second truck stops it dead.  I tried cleaning the frog with some 91% iso, figuring maybe some sort of material from the manufacturing process was on there, but it made no difference.

I've never seen this before and I'm quite vexed.

Oh, also tried a metal wheelset'ed truck and it didn't do anything.  Straight leg also doesn't do anything with the locomotives (all three test units).

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Posted by jrbernier on Saturday, August 16, 2014 3:57 PM

  Sounds like the frog is shorted to the main.  Maybe there is wire or something metal under the turnout.

Jim

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Posted by richhotrain on Saturday, August 16, 2014 4:45 PM

If I understand you correctly, the turnout is brand new, right out of the packaging and onto your layout.

Take the turnout off the layout and test each rail segment for continuity.  I am wondering if a jumper is misplaced.

Sounds like the frog is shorting, badly.

Rich

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Posted by Mark R. on Saturday, August 16, 2014 5:36 PM

Are they Snap switches with the plastic frog ? If so, the problem is that the two diverging rails embedded into the plastic frog are too close together. The wheel tread is wide enough to contact both these rails at the same time causing a short ....

Mark.

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Posted by NittanyLion on Saturday, August 16, 2014 8:13 PM

Yes, its a brand new #6 Custom Line.  Got it about a month ago.  The hobby shop I got it at date stamps their inventory and they'd received it in early July.  There is something different about it compared to other Atlast turnouts, at least as best I remember.  On the bottom of the frog, there's a section of exposed rail instead of a fully plastic frog-bottom.  I don't know if this is significant.

I cleaned the area, to remove any possible metal debris.  Nothing was located and the problem persisted.  I put down masking tape, just in case there was something making contact that evaded me, laid the track on top, still did it.

Checked the wheelsets, everything was in gauge.  I checked the track, but I'm not sure if I interpretted the NMRA gauge correctly on the flange side.  Wheelsets are, like, the easiest to do with that tool.

Took the offending turnout away from the layout and laid it down on a scrap for Homasote (with some sectional track to use as approaches) that I know has no metal fragments or wire or anything anywhere nearby.  Again, the bright orange sparks!  Putting my face much closer than I could before (and with eye protection!), I have observed that the first discharge occurs right as the leading wheel enters the from the diverging leg it does not do so when its entering from the main.  Additional observation shows that there's three locations that cause sparking: entering the frog, right at the V part that I don't know the name of, and when it reaches that rail just beyond the frog when its back to "regular rail."  I should consult a diagram to get those names.  Each wheel causes it at each one of those locations.  Some sort of...something is going on during this testing because its starting to remove the blackening from the frog and expose what appears to be nickel silver rail.  I have suspended testing, as it seems to be causing damage.

richhotrain
 

Take the turnout off the layout and test each rail segment for continuity.  I am wondering if a jumper is misplaced.

 

How would I go about doing this, procedurally?  I have a multimeter.

I don't want to give up on this guy yet, but if I do...is this something I should take up with Atlas, given that it appears that this is defective?

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Posted by cacole on Saturday, August 16, 2014 8:53 PM

I'd take it back to the place of puchase and ask for a replacement or refund on a defective item.

Atlas has had to change manufacturers in China and may be having QC problems.

 

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Posted by Mark R. on Saturday, August 16, 2014 9:37 PM

If you want to continue diagnosing the problem, use your meter to see if there is any kind of power at all in the frog itself. Judging by your description, the frog is solid metal, and out of the package should have no connections to it for power. If there is, the rail running under the bottom of it may inadvertantly be touching the bottom.

Mark. 

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Posted by zstripe on Saturday, August 16, 2014 9:55 PM

I would take it back, it is defective. There are flat metal jumpers under the frog that are separated by the plastic that is injected into the mold....obviously that one does not have the correct amount of insulation. No way to fix it without taking the frog out.

I have had it happen before. I called Atlas and they made arrangements to send me two, no charge, they wanted the defective one though and paid shipping.

Take Care! Big Smile

Frank

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Posted by richhotrain on Sunday, August 17, 2014 5:02 AM

Here is the turnout diagram that I use to identify the various rail segments.

To test for continuity on the various rail segments, dial your multimeter to ohms.  Touch the two metal probes from your multimeter to the two ends of a rail segment.  

For example, if you place each probe near the opposite ends of the throught stock rail, you should get a reading, indicating continuity.  Same for the divergent stock rail.

What I would be most interested in, though, is a continuity test between the divergent point and the divergent frog rail.  Although these are two separate rail segments, they are connected together by built in rail jumpers, so touching one probe to one rail segment and one probe to the other rail segment, you should get a reading, indicating continuity.  You could do the same continuity test for between the through point and the through frog rail. 

Incidentally, the Atlas Custom Line has an isolated metal frog.  So, another informative continuity test is on the frog itself.  If you place one probe on the frog and the other probe of any one of the four adjoining rail segments (through frog rail, divergent frog rail, through closure rail, divergent closure rail), you should not get any reading.  If you do get a reading, the frog is not properly isolated, and that could cause a short.  Check all four adjoining rails with a series of four continuity tests.

Rich

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Posted by retsignalmtr on Sunday, August 17, 2014 5:39 AM

A dab of non metalic nail polish to extend the insulated area of the frog will stop the shorting and sparking. This will have to be reaqpplied when it wears off by use or an abrasive track cleaner. This is nothing new. I have this problem in both HO and N gauges on my home layout and on my clubs layout with Peco switches. The application of the nail polish stops the occurance. Running with DCC, this sparking will cause a short that will stop every train that is running due to the trip speed of the command stations short detection. DC short detection is not as fast so your train just keeps rolling past the bad spot. It usually happens with the loco taking the diverging route through the switch.

Another fix could be to shim the guard rail with Styrene to keep the wheel from reaching the other rail. Cars with metal wheels will do the same thing occasionally.

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Posted by richhotrain on Sunday, August 17, 2014 6:03 AM

retsignalmtr

A dab of non metalic nail polish to extend the insulated area of the frog will stop the shorting and sparking. This will have to be reaqpplied when it wears off by use or an abrasive track cleaner. This is nothing new. I have this problem in both HO and N gauges on my home layout and on my clubs layout with Peco switches. The application of the nail polish stops the occurance. 

 

If this turns out to be the problem, it happens not only with Peco but also Walthers Shinohara, especially the 3-way switches.  

But, this is an Atlas Custom Line #6 turnout, so I will be interested to find out what the OP discovers about the short. I have upwards of 60 of these specific turnouts on my layout and never had that problem.  I am not saying that it is not the problem, however, if this turnout is part of a new batch of the post-production problem in China.  The new batch may have tighter tolerances, intended or not.

Rich

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Posted by retsignalmtr on Sunday, August 17, 2014 9:39 AM

My club (Old Newburgh Model RR Club) had many old Atlas switches with the plastic frogs that were prone to shorting after we switched to DCC. They definately predate the production problems that Atlas is having. Several switches had the metal insulated frogs that didn't have the problem. We changed most of them to Peco long radius but some of the Pecos still have the same problem due to wheels with wider treads.

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Posted by JoeinPA on Sunday, August 17, 2014 10:03 AM

I just recently picked up an Atlas Customline #6 at my LHS that was from a shipment he had just received. So far, all has been good. No sparking or shorting.

Joe

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Posted by richhotrain on Sunday, August 17, 2014 10:34 AM

NittanyLion

Yes, its a brand new #6 Custom Line.  Got it about a month ago.  The hobby shop I got it at date stamps their inventory and they'd received it in early July.  There is something different about it compared to other Atlast turnouts, at least as best I remember.  On the bottom of the frog, there's a section of exposed rail instead of a fully plastic frog-bottom.  I don't know if this is significant.

 

Most of my Atlas Custom Line #6 turnouts are Code 83 and were purchased back in the 2004 to 2007 time period.  On the bottom of each one, just below the hinges for the point rails, Atlas marks the country of origin (i.e., China) and the year of manufacture, in my case all are stamped 1999.  My Atlas Custom Line #6 Code 100 turnouts show country of origin but not the year of manufacture.

The bottom of all of my Atlas Custom Line turnouts, both Code 83 and Code 100, are fully covered in plastic, the bottom of the ties, with one area of exposed metal.  That exposed area of metal is directly beneath the frog.  It sounds like yours is the same as mine with that exposed area of metal.

Rich

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Posted by NittanyLion on Sunday, August 17, 2014 12:18 PM

Ok, so it looks like I have a plan of action for later when I'm doing laundry and have time to sit down and tinker (compared to right now which is internet while eating lunch).

This affair is bothersome because its the first Atlas turnout I've ever had that gave me any real trouble.  That and taking it back to the store is, uh, shall we say not cost effective as it is almost six hours away in Western Pennsylvania, whereas I am in Northern Virginia.  Made a stop there on my way back from Cleveland last month.  With this turnout, I'd complete all tracklaying.  So close!

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Posted by richhotrain on Sunday, August 17, 2014 3:19 PM

You are to be admired for sticking with it and trying to solve the problem.  It should be fixable.  Keep us posted.

Rich

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Posted by NittanyLion on Sunday, August 17, 2014 6:13 PM

Ok, so I sat down and got out the multi-meter.

Turns out the through closure rail isn't isolated from the frog.  This would also explain why the discharge doesn't occur when the locomotive goes through rather than diverges, doesn't it?  Seems more obvious after the fact that the fault was there.

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Posted by richhotrain on Sunday, August 17, 2014 7:21 PM

NittanyLion

Turns out the through closure rail isn't isolated from the frog.  This would also explain why the discharge doesn't occur when the locomotive goes through rather than diverges, doesn't it?  

Yes, that makes sense.  In a way, it is operating like an electrofrog.

Now, the question is, how to fix it.

Since the frog is supposed to be isolated, there should be a plastic gap between the frog and the through closure rail.  Is it there or is the through closure rail touching the frog?

The other possible issue is the jumper embedded under the ties.  It connects the through closure rail to the through frog rail.  Assuming that you get a continuity reading between those two rails, it may be that the jumper is also making contact with the metal frog, but you cannot see it since the jumper is embedded in the plastic.

What can you tell when you look closely?

Rich

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Posted by cacole on Sunday, August 17, 2014 9:10 PM

Just be aware that any hacking, cutting, filing, etc. will invalidate whatever warranty the product may have had from Atlas, and if you can't solve the problem you may wind up having to purchase another turnout.

 

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Posted by NittanyLion on Sunday, August 17, 2014 10:54 PM

Frog does seem to be isolated.  I used my digital camera as an ad hoc microscope to get a clear view at much higher magnification than my eyes have.  Nothing looked amiss or very different than similiar photos of a turnout with no issues.  The only difference between the two (aside from one being RH and the other LH) is the faulty one is a difference of .004 in the spacing between the frog and through closure rail.

I did alter the turnout itself, trimming about half an inch of rail off one end to make it fit, so I've pretty much assumed that any sort of warranty is long gone.  Figure if I can get the thing to work, I might as well, since I'm already in for...however much it cost.

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Posted by modelmaker51 on Sunday, August 17, 2014 11:43 PM

Just trimming the approach rails will not negate your warranty.

Jay 

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Posted by zstripe on Monday, August 18, 2014 2:44 AM

It was explained to me by Atlas that the frog area has two thin flat metal jumpers that are sandwiched in under the frog with the frog on top then inserted in the mold and then the liquid hot plastic is injected into the mold at high pressure and creates a wafer thin insulation between the jumpers and the frog and also the insulated gaps on the rails that you can see. They were having this problem and had corrected it.....but some had slipped through the system and apparrantly you have one. The frog is touching one of the jumpers, due to lack of plastic that separates them.

You can cut four new gaps, two before and two after,right through the plastic gaps that are there and fill in with a medium type CA that you can file and completely isolate the frog again, would probably be the best solution, if you want to go through all that. That would be the only way to power the frog, should you want to.

Your choice, My experience.

Take Care! Big Smile

Frank

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Posted by richhotrain on Monday, August 18, 2014 6:14 AM

So, the frog appears to be fully gapped on the surface of the turnout.  That would indicate that the source of power to the frog is the jumper embedded in the ties on the underside of the turnout.  Take a look at the diagram below.  

The upper illustration shows the correct polarity of the turnout, using red and blue colors for the rails.  The frog parts are colored black.  The dotted lines represent the embedded jumpers connecting the closure rails to the frog rails.  The arrow pointing to the gap shows the plastic gap on the surface of the turnout.

The lower illustration shows the result of the through closure rail making electrical contact with the frog.  The frog takes on the polarity of the through closure rail (blue), creating a short on the divergent side but no short on the straight through side.

Since there is a plastic gap on the surface of the turnout, and there does appear to be a separation between the through closure rail and the frog, the only source of power to the frog has to be coming from the embedded jumper on the underside of the turnout.

Double check your continuity to be sure that the only source of power to the frog is the through closure rail.  If it is, then visually examine the plastic gap on the surface of the turnout to be certain that the end of the through closure rail is not touching the frog at any point.  If there is no surface contact between the through closure rail and the frog, then it can only be that embedded jumper.

Rich

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Posted by richhotrain on Monday, August 18, 2014 6:26 AM

zstripe

It was explained to me by Atlas that the frog area has two thin flat metal jumpers that are sandwiched in under the frog with the frog on top then inserted in the mold and then the liquid hot plastic is injected into the mold at high pressure and creates a wafer thin insulation between the jumpers and the frog and also the insulated gaps on the rails that you can see. They were having this problem and had corrected it.....but some had slipped through the system and apparrantly you have one. The frog is touching one of the jumpers, due to lack of plastic that separates them.

If you look at the underside of an Atlas Custom Line #6 turnout, you will see an exposed piece of metal laid under the frog in parallel with the divergent closure rail and the divergent frog rail.  I believe that this exposed piece of metal is the part that Atlas added to simplify powering the frog, should someone choose to do so.  That being the case, the jumpers connecting the closure rails to the frog rails would be placed between the frog and this exposed piece of metal.  So, as opposed to the jumper touching the frog, it may be that the jumper is contacting this exposed piece of metal which itself has contact with the frog.  Of course, the only way to find out would be to dig out that exposed piece of metal.  If you have no intention of intentionally powering the frog at some point in the future, you could remove that exposed piece of metal.

Rich

Edit Note:  See my later reply about that exposed piece of metal.

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Posted by rrinker on Monday, August 18, 2014 6:55 AM

 No, Zstripe has it right. The closure rails continue under the frog to the appropriate diverging frog rail, tha's how they are all routes powered rather than power routing. On the very bottom you see the metal of the one closure rail, above that in the plastic is the second closure rail, and above that sits the frog. The frog power connection is the little tab with a hole in it on the one side.

 This is why I put feeders on all 3 legs of Atlas Custom Line turnouts - the ones on the diverging side give a solid power feed to the closure rails that doesn't depend on joiners or rivets, it goes through that solid connection embedded in the plastic.

 I've had the frog pop off one while attempting to solder a feeder to the frog (not going to happen, don't even try. Instead, brass screw in the hole and solder to that). Underneath the frog is just a thin layer of plastic insulating the upper of the two flattened pieces that connect the closure rail to the frog rail. Scratch through that plastic and you will see the metal (and ruin the turnout). If that part of the mold didn;t fill properly, the frog will be contacting the rail causing the issue described. If the missing part was the plastic between the two closure rails, then the whole thing would be a dead short at all times.

                             --Randy

 


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Posted by richhotrain on Monday, August 18, 2014 7:21 AM

OK, I went back and did a continuity check on the exposed metal piece on the underside of the turnout.  As Randy indicates, that exposed metal piece running parallel to the divergent rails is the jumper connecting the divergent closure rail to the divergent frog rail.

So, the jumper connecting the through closure rail to the through frog rail is embedded in the plastic ties between the frog and the jumper for the divergent rails.

Since the through closure rail is powering the frog, Nittany Lion is going to have to remove the exposed jumper to get at the embedded jumper, or else remove the frog to get at the offending jumper.

Rich

Edit Note:  As I re-read your reply, Randy, it looks like you are saying that these are not jumpers at all but, rather, a continuation of the rails under the frog, meant to be separated by plastic molding.   Interesting!

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Posted by richhotrain on Monday, August 18, 2014 10:19 AM

rrinker

I've had the frog pop off one while attempting to solder a feeder to the frog.

Not long ago, I was removing an Atlas Custom Line #6 Code 83 turnout on my layout for repair.  As I was removing the turnout, the frog fell out.  So, the frog is not necessarily hard to remove.

Incidentally, I have never powered a frog, but on the Atlas Custom Line turnout, there is a small metal extension on the frog, a tab with a hole in the center.  As I now realize, that tab with the hole in the center of it is there for the purpose of inserting a metal screw to bring power to the frog, should you so choose.

Rich

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Posted by richhotrain on Monday, August 18, 2014 11:05 AM

OK, I couldn't resist the impulse any longer.  

I have an old, damaged, out of use, Atlas Custom Line #6 turnout with an isolated metal frog, DCC Friendly.

So, I put on the Optivisor and examined it more closely.  There are jumpers, thin metal strips, that connect the two closure rails to their respective frog rails.  The jumper connecting the divergent rails on the #6 turnout is exposed on the underside of the turnout.  The jumper connecting the through rails is above the divergent rails jumper, closer to the frog, embedded in plastic.

If you gently twist the turnout back and forth, the frog can be popped out with the point of an Exacto blade, without damaging the turnout.  This will reveal the plastic bed upon which the frog sits in place.  As I examined the turnout with the frog removed, I could observe that the plastic gaps do, indeed, insulate the frog from the four adjacent rails. I also observed no sign of the metal jumper connecting the through rails.

If Nittany Lion were to do this, I suspect that he will see a spot where the metal jumper for the through rails is exposed under the frog.  Cover it with a thin layer of 2 part epoxy, and he would be good to go.  

Incidentally, I mentioned in one of my earlier replies that I inadvertently had a frog pop out of place a few months back.  I used thick CA to glue it back in place, and it has held up quite well ever since.

Rich

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Posted by rrinker on Monday, August 18, 2014 5:07 PM

 Yes, the one I popped out while attempting to solder to it, I just glued back in place with CA and I ran trains over it for another couple of years before I moved and it was fine. I may have actually been attempting to tap the hole after soldering failed - this turnout was already in place, and the force of this may have been what popped the frog out. Now I just use a plain old brass screw, don;t tap, and the screw isn't even 'officially' a self tapping screw. The difference is, I do it BEFORE putting the turnout in place. Thus I can support the frog while driving the screw in so it doesn;t get popped out.

                    --Randy


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Posted by NittanyLion on Monday, August 18, 2014 5:55 PM

Read all the replies since last night.

Managed to get the frog off (which I didn't even know could be removed), only did some light damage to the plastic just outside the frog.  Shouldn't be too noticeable after filing and painting.  Also, the turnout slipped once and I speared myself with the end of the rail.  I figure only one cut to myself when prying something apart with an x-acto knife is a victory.

Now, if I'm interpretting what everyone's told me, there should be no exposed metal of any kind in the, uh, sub-frog, right?  In the sub-frog, there's four circles cast into the plastic.  I assume some sort of alignment system for the frog.  One of these is partially hollow and there's a tiny little finger of metal sticking up in there.  On the matching circle on the base of the frog, there's some metal flash sticking down into the hole.

If I file off that flash and plug that hole, everything should be good, right?

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